The metaslab_check_free() function only needs to be called in the
GANG|DEDUP|etc case because zio_free_sync() will internally call
metaslab_check_free().
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Richard Yao <richard.yao@alumni.stonybrook.edu>
Signed-off-by: Finix1979 <yancw@info2soft.com>
Closes#13977
ZED does not take any action for disk removal events if there is no
spare VDEV available. Added zpool_vdev_remove_wanted() in libzfs
and vdev_remove_wanted() in vdev.c to remove the VDEV through ZED
on removal event. This means that if you are running zed and
remove a disk, it will be properly marked as REMOVED.
Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Reviewed-by: Ryan Moeller <ryan@iXsystems.com>
Reviewed-by: Tony Hutter <hutter2@llnl.gov>
Signed-off-by: Ameer Hamza <ahamza@ixsystems.com>
Closes#13797
In #13871, zfs_vdev_aggregation_limit_non_rotating and
zfs_vdev_aggregation_limit being signed was pointed out as a possible
reason not to eliminate an unnecessary MAX(unsigned, 0) since the
unsigned value was assigned from them.
There is no reason for these module parameters to be signed and upon
inspection, it was found that there are a number of other module
parameters that are signed, but should not be, so we make them unsigned.
Making them unsigned made it clear that some other variables in the code
should also be unsigned, so we also make those unsigned. This prevents
users from setting negative values that could potentially cause bad
behaviors. It also makes the code slightly easier to understand.
Mostly module parameters that deal with timeouts, limits, bitshifts and
percentages are made unsigned by this. Any that are boolean are left
signed, since whether booleans should be considered signed or unsigned
does not matter.
Making zfs_arc_lotsfree_percent unsigned caused a
`zfs_arc_lotsfree_percent >= 0` check to become redundant, so it was
removed. Removing the check was also necessary to prevent a compiler
error from -Werror=type-limits.
Several end of line comments had to be moved to their own lines because
replacing int with uint_t caused us to exceed the 80 character limit
enforced by cstyle.pl.
The following were kept signed because they are passed to
taskq_create(), which expects signed values and modifying the
OpenSolaris/Illumos DDI is out of scope of this patch:
* metaslab_load_pct
* zfs_sync_taskq_batch_pct
* zfs_zil_clean_taskq_nthr_pct
* zfs_zil_clean_taskq_minalloc
* zfs_zil_clean_taskq_maxalloc
* zfs_arc_prune_task_threads
Also, negative values in those parameters was found to be harmless.
The following were left signed because either negative values make
sense, or more analysis was needed to determine whether negative values
should be disallowed:
* zfs_metaslab_switch_threshold
* zfs_pd_bytes_max
* zfs_livelist_min_percent_shared
zfs_multihost_history was made static to be consistent with other
parameters.
A number of module parameters were marked as signed, but in reality
referenced unsigned variables. upgrade_errlog_limit is one of the
numerous examples. In the case of zfs_vdev_async_read_max_active, it was
already uint32_t, but zdb had an extern int declaration for it.
Interestingly, the documentation in zfs.4 was right for
upgrade_errlog_limit despite the module parameter being wrongly marked,
while the documentation for zfs_vdev_async_read_max_active (and friends)
was wrong. It was also wrong for zstd_abort_size, which was unsigned,
but was documented as signed.
Also, the documentation in zfs.4 incorrectly described the following
parameters as ulong when they were int:
* zfs_arc_meta_adjust_restarts
* zfs_override_estimate_recordsize
They are now uint_t as of this patch and thus the man page has been
updated to describe them as uint.
dbuf_state_index was left alone since it does nothing and perhaps should
be removed in another patch.
If any module parameters were missed, they were not found by `grep -r
'ZFS_MODULE_PARAM' | grep ', INT'`. I did find a few that grep missed,
but only because they were in files that had hits.
This patch intentionally did not attempt to address whether some of
these module parameters should be elevated to 64-bit parameters, because
the length of a long on 32-bit is 32-bit.
Lastly, it was pointed out during review that uint_t is a better match
for these variables than uint32_t because FreeBSD kernel parameter
definitions are designed for uint_t, whose bit width can change in
future memory models. As a result, we change the existing parameters
that are uint32_t to use uint_t.
Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Neal Gompa <ngompa@datto.com>
Signed-off-by: Richard Yao <richard.yao@alumni.stonybrook.edu>
Closes#13875
This type of recv is used to heal corrupted data when a replica
of the data already exists (in the form of a send file for example).
With the provided send stream, corrective receive will read from
disk blocks described by the WRITE records. When any of the reads
come back with ECKSUM we use the data from the corresponding WRITE
record to rewrite the corrupted block.
Reviewed-by: Paul Dagnelie <pcd@delphix.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Paul Zuchowski <pzuchowski@datto.com>
Signed-off-by: Alek Pinchuk <apinchuk@axcient.com>
Closes#9372
It may happen that scan bookmark points to a block that was turned
into a part of a big hole. In such case dsl_scan_visitbp() may skip
it and dsl_scan_check_resume() will not be called for it. As result
new scan suspend won't be possible until the end of the object, that
may take hours if the object is a multi-terabyte ZVOL on a slow HDD
pool, stretching TXG to all that time, creating all sorts of problems.
This patch changes the resume condition to any greater or equal block,
so even if we miss the bookmarked block, the next one we find will
delete the bookmark, allowing new suspend.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Ryan Moeller <ryan@iXsystems.com>
Signed-off-by: Alexander Motin <mav@FreeBSD.org>
Sponsored-By: iXsystems, Inc.
Closes#13643
We want `zpool import` to be highly robust and never panic, even
when encountering corrupt metadata. This is already handled in the
arc_read() code path, which covers most cases, but spa_load_verify_cb()
relies on zio_read() and is responsible for verifying the block pointer.
During import it is also possible to encounter blocks pointers which
contain ZIO_COMPRESS_INHERIT and ZIO_CHECKSUM_INHERIT values. Relax
the verification function slightly to allow this.
Futhermore, extend dsl_scan_recurse() to verify the block pointer
contents of level zero blocks which are not of type DMU_OT_DNODE or
DMU_OT_OBJSET. This is handled by arc_read() in the other cases.
Reviewed-by: Paul Dagnelie <pcd@delphix.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#13124Closes#13360
Increase the default allowed maximum recordsize from 1M to 16M.
As described in the zfs(4) man page, there are significant costs
which need to be considered before using very large blocks.
However, there are scenarios where they make good sense and
it should no longer be necessary to artificially restrict their
use behind a module option.
Note that for 32-bit platforms we continue to leave this
restriction in place due to the limited virtual address space
available (256-512MB). On these systems only a handful
of blocks could be cached at any one time severely impacting
performance and potentially stability.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Signed-off-by: Rich Ercolani <rincebrain@gmail.com>
Closes#12830Closes#13302
bcopy() has a confusing argument order and is actually a move, not a
copy; they're all deprecated since POSIX.1-2001 and removed in -2008,
and we shim them out to mem*() on Linux anyway
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Ahelenia Ziemiańska <nabijaczleweli@nabijaczleweli.xyz>
Closes#12996
Raw sending from pool1/encrypted with ashift=9 to pool2/encrypted with
ashift=12 results to failure when mounting pool2/encrypted (Input/Output
error). Notably, the opposite, raw sending from a greater ashift to a
lower one does not fail.
This happens because zio_compress_write() falsely checks only
ZIO_FLAG_RAW_COMPRESS and not ZIO_FLAG_RAW_ENCRYPT which is also set in
encrypted raw send streams. In this case it rounds up the psize and if
not equal to the zio->io_size it modifies the block by zeroing out
the extra bytes. Because this happens in a SA attr. registration object
(type=46), the decryption fails upon mounting the filesystem, and zpool
status falsely reports an error.
Fix this by checking both ZIO_FLAG_RAW_COMPRESS and ZIO_FLAG_RAW_ENCRYPT
before deciding whether to zero-pad a block.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: George Amanakis <gamanakis@gmail.com>
Closes#13067Closes#13074
69 CSTYLED BEGINs remain, appx. 30 of which can be removed if cstyle(1)
had a useful policy regarding
CALL(ARG1,
ARG2,
ARG3);
above 2 lines. As it stands, it spits out *both*
sysctl_os.c: 385: continuation line should be indented by 4 spaces
sysctl_os.c: 385: indent by spaces instead of tabs
which is very cool
Another >10 could be fixed by removing "ulong" &al. handling.
I don't foresee anyone actually using it intentionally
(does it even exist in modern headers? why did it in the first place?).
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Ahelenia Ziemiańska <nabijaczleweli@nabijaczleweli.xyz>
Closes#12993
Evaluated every variable that lives in .data (and globals in .rodata)
in the kernel modules, and constified/eliminated/localised them
appropriately. This means that all read-only data is now actually
read-only data, and, if possible, at file scope. A lot of previously-
global-symbols became inlinable (and inlined!) constants. Probably
not in a big Wowee Performance Moment, but hey.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Ahelenia Ziemiańska <nabijaczleweli@nabijaczleweli.xyz>
Closes#12899
Add properties, similar to pool properties, to each vdev.
This makes use of the existing per-vdev ZAP that was added as
part of device evacuation/removal.
A large number of read-only properties are exposed,
many of the members of struct vdev_t, that provide useful
statistics.
Adds support for read-only "removing" vdev property.
Adds the "allocating" property that defaults to "on" and
can be set to "off" to prevent future allocations from that
top-level vdev.
Supports user-defined vdev properties.
Includes support for properties.vdev in SYSFS.
Co-authored-by: Allan Jude <allan@klarasystems.com>
Co-authored-by: Mark Maybee <mark.maybee@delphix.com>
Reviewed-by: Matthew Ahrens <mahrens@delphix.com>
Reviewed-by: Mark Maybee <mark.maybee@delphix.com>
Signed-off-by: Allan Jude <allan@klarasystems.com>
Closes#11711
The block pointer verification check in arc_read() should also
cover embedded block pointers. While highly unlikely, accessing
a damaged block pointer can result in panic. To further harden
the code extend the existing check to include embedded block
pointers and add a comment explaining the rational for this
sanity check. Lastly, correct a flaw in zfs_blkptr_verify()
so the error count is checked even when checking a untrusted
config to verify the non-pool-specific portions of a block
pointer.
Reviewed-by: Matthew Ahrens <mahrens@delphix.com>
Reviewed-by: Tony Nguyen <tony.nguyen@delphix.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#12535
We round up the psize to the nearest multiple of the asize or to the
lsize, whichever is smaller. Once that's done, we allocate a new
buffer of the appropriate size, zero the tail, and copy the data
into it. This adds a small performance cost to these kinds of writes,
but fixes the bookkeeping problems.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Matthew Ahrens <mahrens@delphix.com>
Co-authored-by: Matthew Ahrens <matthew.ahrens@delphix.com>
Signed-off-by: Paul Dagnelie <pcd@delphix.com>
Closes#12522Closes#8462
Remove mc_lock use from metaslab_class_throttle_*(). The math there
is based on refcounts and so atomic, so the only race possible there
is between zfs_refcount_count() and zfs_refcount_add(). But in most
cases metaslab_class_throttle_reserve() is called with the allocator
lock held, which covers the race. In cases where the lock is not
held, GANG_ALLOCATION() or METASLAB_MUST_RESERVE are set, and so we
do not use zfs_refcount_count(). And even if we assume some other
non-existing scenario, the worst that may happen from this race is
few more I/Os get to allocation earlier, that is not a problem.
Move locks and data of different allocators into different cache
lines to avoid false sharing. Group spa_alloc_* arrays together
into single array of aligned struct spa_alloc spa_allocs. Align
struct metaslab_class_allocator.
Reviewed-by: Paul Dagnelie <pcd@delphix.com>
Reviewed-by: Ryan Moeller <ryan@iXsystems.com>
Reviewed-by: Don Brady <don.brady@delphix.com>
Signed-off-by: Alexander Motin <mav@FreeBSD.org>
Sponsored-By: iXsystems, Inc.
Closes#12314
* zio: avoid callback typecasting
* zil: avoid zil_itxg_clean() callback typecasting
* zpl: decouple zpl_readpage() into two separate callbacks
* nvpair: explicitly declare callbacks for xdr_array()
* linux/zfs_nvops: don't use external iput() as a callback
* zcp_synctask: don't use fnvlist_free() as a callback
* zvol: don't use ops->zv_free() as a callback for taskq_dispatch()
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Mark Maybee <mark.maybee@delphix.com>
Signed-off-by: Alexander Lobakin <alobakin@pm.me>
Closes#12260
ZFS loves using %llu for uint64_t, but that requires a cast to not
be noisy - which is even done in many, though not all, places.
Also a couple places used %u for uint64_t, which were promoted
to %llu.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Rich Ercolani <rincebrain@gmail.com>
Closes#12233
In case we have I/O and try to remove an L2ARC device a deadlock might
occur. arc_read()->zio_read()->zfs_blkptr_verify() waits for SCL_VDEV
to be dropped while holding the hash_lock. However, spa_l2cache_load()
holds SCL_ALL and waits for the hash_lock in l2arc_evict().
Fix this by moving zfs_blkptr_verify() to the top top arc_read() before
the hash_lock is taken. Verify the block pointer and return a checksum
error if damaged rather than halting the system, by using
BLK_VERIFY_LOG instead of BLK_VERIFY_HALT.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Mark Maybee <mark.maybee@delphix.com>
Signed-off-by: George Amanakis <gamanakis@gmail.com>
Closes#12054
This deduplicates 2 sets of caches which use the same allocation size.
Memory savings fluctuate a lot, one sample result is FreeBSD running
"make buildworld" saving ~180MB RAM in reduced page count associated
with zio caches.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Mateusz Guzik <mjguzik@gmail.com>
Closes#11877
Fix NULL pointer dereference when reporting
checksum error for gang block in zio_done.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Paul Zuchowski <pzuchowski@datto.com>
Closes#11872Closes#11896
For gang blocks, `DVA_GET_ASIZE()` is the total space allocated for the
gang DVA including its children BP's. The space allocated at each DVA's
vdev/offset is `vdev_psize_to_asize(vd, SPA_GANGBLOCKSIZE)`.
This commit makes this relationship more clear by using a helper
function, `vdev_gang_header_asize()`, for the space allocated at the
gang block's vdev/offset.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Matthew Ahrens <mahrens@delphix.com>
Closes#11744
The RAIDZ and DRAID code is responsible for reporting checksum errors on
their child vdevs. Checksum errors represent events where a disk
returned data or parity that should have been correct, but was not. In
other words, these are instances of silent data corruption. The
checksum errors show up in the vdev stats (and thus `zpool status`'s
CKSUM column), and in the event log (`zpool events`).
Note, this is in contrast with the more common "noisy" errors where a
disk goes offline, in which case ZFS knows that the disk is bad and
doesn't try to read it, or the device returns an error on the requested
read or write operation.
RAIDZ/DRAID generate checksum errors via three code paths:
1. When RAIDZ/DRAID reconstructs a damaged block, checksum errors are
reported on any children whose data was not used during the
reconstruction. This is handled in `raidz_reconstruct()`. This is the
most common type of RAIDZ/DRAID checksum error.
2. When RAIDZ/DRAID is not able to reconstruct a damaged block, that
means that the data has been lost. The zio fails and an error is
returned to the consumer (e.g. the read(2) system call). This would
happen if, for example, three different disks in a RAIDZ2 group are
silently damaged. Since the damage is silent, it isn't possible to know
which three disks are damaged, so a checksum error is reported against
every child that returned data or parity for this read. (For DRAID,
typically only one "group" of children is involved in each io.) This
case is handled in `vdev_raidz_cksum_finish()`. This is the next most
common type of RAIDZ/DRAID checksum error.
3. If RAIDZ/DRAID is not able to reconstruct a damaged block (like in
case 2), but there happens to be additional copies of this block due to
"ditto blocks" (i.e. multiple DVA's in this blkptr_t), and one of those
copies is good, then RAIDZ/DRAID compares each sector of the data or
parity that it retrieved with the good data from the other DVA, and if
they differ then it reports a checksum error on this child. This
differs from case 2 in that the checksum error is reported on only the
subset of children that actually have bad data or parity. This case
happens very rarely, since normally only metadata has ditto blocks. If
the silent damage is extensive, there will be many instances of case 2,
and the pool will likely be unrecoverable.
The code for handling case 3 is considerably more complicated than the
other cases, for two reasons:
1. It needs to run after the main raidz read logic has completed. The
data RAIDZ read needs to be preserved until after the alternate DVA has
been read, which necessitates refcounts and callbacks managed by the
non-raidz-specific zio layer.
2. It's nontrivial to map the sections of data read by RAIDZ to the
correct data. For example, the correct data does not include the parity
information, so the parity must be recalculated based on the correct
data, and then compared to the parity that was read from the RAIDZ
children.
Due to the complexity of case 3, the rareness of hitting it, and the
minimal benefit it provides above case 2, this commit removes the code
for case 3. These types of errors will now be handled the same as case
2, i.e. the checksum error will be reported against all children that
returned data or parity.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Matthew Ahrens <mahrens@delphix.com>
Closes#11735
Fix regression seen in issue #11545 where checksum errors
where not being counted or showing up in a zpool event.
Reviewed-by: Matthew Ahrens <mahrens@delphix.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Don Brady <don.brady@delphix.com>
Closes#11609
Mixing ZIL and normal allocations has several problems:
1. The ZIL allocations are allocated, written to disk, and then a few
seconds later freed. This leaves behind holes (free segments) where the
ZIL blocks used to be, which increases fragmentation, which negatively
impacts performance.
2. When under moderate load, ZIL allocations are of 128KB. If the pool
is fairly fragmented, there may not be many free chunks of that size.
This causes ZFS to load more metaslabs to locate free segments of 128KB
or more. The loading happens synchronously (from zil_commit()), and can
take around a second even if the metaslab's spacemap is cached in the
ARC. All concurrent synchronous operations on this filesystem must wait
while the metaslab is loading. This can cause a significant performance
impact.
3. If the pool is very fragmented, there may be zero free chunks of
128KB or more. In this case, the ZIL falls back to txg_wait_synced(),
which has an enormous performance impact.
These problems can be eliminated by using a dedicated log device
("slog"), even one with the same performance characteristics as the
normal devices.
This change sets aside one metaslab from each top-level vdev that is
preferentially used for ZIL allocations (vdev_log_mg,
spa_embedded_log_class). From an allocation perspective, this is
similar to having a dedicated log device, and it eliminates the
above-mentioned performance problems.
Log (ZIL) blocks can be allocated from the following locations. Each
one is tried in order until the allocation succeeds:
1. dedicated log vdevs, aka "slog" (spa_log_class)
2. embedded slog metaslabs (spa_embedded_log_class)
3. other metaslabs in normal vdevs (spa_normal_class)
The space required for the embedded slog metaslabs is usually between
0.5% and 1.0% of the pool, and comes out of the existing 3.2% of "slop"
space that is not available for user data.
On an all-ssd system with 4TB storage, 87% fragmentation, 60% capacity,
and recordsize=8k, testing shows a ~50% performance increase on random
8k sync writes. On even more fragmented systems (which hit problem #3
above and call txg_wait_synced()), the performance improvement can be
arbitrarily large (>100x).
Reviewed-by: Serapheim Dimitropoulos <serapheim@delphix.com>
Reviewed-by: George Wilson <gwilson@delphix.com>
Reviewed-by: Don Brady <don.brady@delphix.com>
Reviewed-by: Mark Maybee <mark.maybee@delphix.com>
Signed-off-by: Matthew Ahrens <mahrens@delphix.com>
Closes#11389
The `abd_get_offset_*()` routines create an abd_t that references
another abd_t, and doesn't allocate any pages/buffers of its own. In
some workloads, these routines may be called frequently, to create many
abd_t's representing small pieces of a single large abd_t. In
particular, the upcoming RAIDZ Expansion project makes heavy use of
these routines.
This commit adds the ability for the caller to allocate and provide the
abd_t struct to a variant of `abd_get_offset_*()`. This eliminates the
cost of allocating the abd_t and performing the accounting associated
with it (`abdstat_struct_size`). The RAIDZ/DRAID code uses this for
the `rc_abd`, which references the zio's abd. The upcoming RAIDZ
Expansion project will leverage this infrastructure to increase
performance of reads post-expansion by around 50%.
Additionally, some of the interfaces around creating and destroying
abd_t's are cleaned up. Most significantly, the distinction between
`abd_put()` and `abd_free()` is eliminated; all types of abd_t's are
now disposed of with `abd_free()`.
Reviewed-by: Brian Atkinson <batkinson@lanl.gov>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Matthew Ahrens <mahrens@delphix.com>
Issue #8853Closes#11439
On a system with very high fragmentation, we may need to do lots of gang
allocations (e.g. most indirect block allocations (~50KB) may need to
gang). Before failing a "normal" allocation and resorting to ganging, we
try every metaslab. This has the impact of loading every metaslab (not
a huge deal since we now typically keep all metaslabs loaded), and also
iterating over every metaslab for every failing allocation. If there are
many metaslabs (more than the typical ~200, e.g. due to vdev expansion
or very large vdevs), the CPU cost of this iteration can be very
impactful. This iteration is done with the mg_lock held, creating long
hold times and high lock contention for concurrent allocations,
ultimately causing long txg sync times and poor application performance.
To address this, this commit changes the behavior of "normal" (not
try_hard, not ZIL) allocations. These will now only examine the 100
best metaslabs (as determined by their ms_weight). If none of these
have a large enough free segment, then the allocation will fail and
we'll fall back on ganging.
To accomplish this, we will now (normally) gang before doing a
`try_hard` allocation. Non-try_hard allocations will only examine the
100 best metaslabs of each vdev. In summary, we will first try normal
allocation. If that fails then we will do a gang allocation. If that
fails then we will do a "try hard" gang allocation. If that fails then
we will have a multi-layer gang block.
Reviewed-by: Paul Dagnelie <pcd@delphix.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Matthew Ahrens <mahrens@delphix.com>
Closes#11327
Metaslab rotor and aliquot are used to distribute workload between
vdevs while keeping some locality for logically adjacent blocks. Once
multiple allocators were introduced to separate allocation of different
objects it does not make much sense for different allocators to write
into different metaslabs of the same metaslab group (vdev) same time,
competing for its resources. This change makes each allocator choose
metaslab group independently, colliding with others only sporadically.
Test including simultaneous write into 4 files with recordsize of 4KB
on a striped pool of 30 disks on a system with 40 logical cores show
reduction of vdev queue lock contention from 54 to 27% due to better
load distribution. Unfortunately it won't help much ZVOLs yet since
only one dataset/ZVOL is synced at a time, and so for the most part
only one allocator is used, but it may improve later.
While there, to reduce the number of pointer dereferences change
per-allocator storage for metaslab classes and groups from several
separate malloc()'s to variable length arrays at the ends of the
original class and group structures.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Matthew Ahrens <mahrens@delphix.com>
Signed-off-by: Alexander Motin <mav@FreeBSD.org>
Closes#11288
This patch adds a new top-level vdev type called dRAID, which stands
for Distributed parity RAID. This pool configuration allows all dRAID
vdevs to participate when rebuilding to a distributed hot spare device.
This can substantially reduce the total time required to restore full
parity to pool with a failed device.
A dRAID pool can be created using the new top-level `draid` type.
Like `raidz`, the desired redundancy is specified after the type:
`draid[1,2,3]`. No additional information is required to create the
pool and reasonable default values will be chosen based on the number
of child vdevs in the dRAID vdev.
zpool create <pool> draid[1,2,3] <vdevs...>
Unlike raidz, additional optional dRAID configuration values can be
provided as part of the draid type as colon separated values. This
allows administrators to fully specify a layout for either performance
or capacity reasons. The supported options include:
zpool create <pool> \
draid[<parity>][:<data>d][:<children>c][:<spares>s] \
<vdevs...>
- draid[parity] - Parity level (default 1)
- draid[:<data>d] - Data devices per group (default 8)
- draid[:<children>c] - Expected number of child vdevs
- draid[:<spares>s] - Distributed hot spares (default 0)
Abbreviated example `zpool status` output for a 68 disk dRAID pool
with two distributed spares using special allocation classes.
```
pool: tank
state: ONLINE
config:
NAME STATE READ WRITE CKSUM
slag7 ONLINE 0 0 0
draid2:8d:68c:2s-0 ONLINE 0 0 0
L0 ONLINE 0 0 0
L1 ONLINE 0 0 0
...
U25 ONLINE 0 0 0
U26 ONLINE 0 0 0
spare-53 ONLINE 0 0 0
U27 ONLINE 0 0 0
draid2-0-0 ONLINE 0 0 0
U28 ONLINE 0 0 0
U29 ONLINE 0 0 0
...
U42 ONLINE 0 0 0
U43 ONLINE 0 0 0
special
mirror-1 ONLINE 0 0 0
L5 ONLINE 0 0 0
U5 ONLINE 0 0 0
mirror-2 ONLINE 0 0 0
L6 ONLINE 0 0 0
U6 ONLINE 0 0 0
spares
draid2-0-0 INUSE currently in use
draid2-0-1 AVAIL
```
When adding test coverage for the new dRAID vdev type the following
options were added to the ztest command. These options are leverages
by zloop.sh to test a wide range of dRAID configurations.
-K draid|raidz|random - kind of RAID to test
-D <value> - dRAID data drives per group
-S <value> - dRAID distributed hot spares
-R <value> - RAID parity (raidz or dRAID)
The zpool_create, zpool_import, redundancy, replacement and fault
test groups have all been updated provide test coverage for the
dRAID feature.
Co-authored-by: Isaac Huang <he.huang@intel.com>
Co-authored-by: Mark Maybee <mmaybee@cray.com>
Co-authored-by: Don Brady <don.brady@delphix.com>
Co-authored-by: Matthew Ahrens <mahrens@delphix.com>
Co-authored-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Mark Maybee <mmaybee@cray.com>
Reviewed-by: Matt Ahrens <matt@delphix.com>
Reviewed-by: Tony Hutter <hutter2@llnl.gov>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#10102
It is a leftover from illumos always set to NULL and introducing a
spurious difference between zio_buf and zio_data_buf.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Mateusz Guzik <mjguzik@gmail.com>
Closes#11188
Current CPU_SEQID users don't care about possibly changing CPU ID, but
enclose it within kpreempt disable/enable in order to fend off warnings
from Linux's CONFIG_DEBUG_PREEMPT.
There is no need to do it. The expected way to get CPU ID while allowing
for migration is to use raw_smp_processor_id.
In order to make this future-proof this patch keeps CPU_SEQID as is and
introduces CPU_SEQID_UNSTABLE instead, to make it clear that consumers
explicitly want this behavior.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Ryan Moeller <ryan@iXsystems.com>
Reviewed-by: Matt Macy <mmacy@FreeBSD.org>
Signed-off-by: Mateusz Guzik <mjguzik@gmail.com>
Closes#11142
Refer to the correct section or alternative for FreeBSD and Linux.
Reviewed-by: George Melikov <mail@gmelikov.ru>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Ryan Moeller <ryan@iXsystems.com>
Closes#11132
Duplicate io and checksum ereport events can misrepresent that
things are worse than they seem. Ideally the zpool events and the
corresponding vdev stat error counts in a zpool status should be
for unique errors -- not the same error being counted over and over.
This can be demonstrated in a simple example. With a single bad
block in a datafile and just 5 reads of the file we end up with a
degraded vdev, even though there is only one unique error in the pool.
The proposed solution to the above issue, is to eliminate duplicates
when posting events and when updating vdev error stats. We now save
recent error events of interest when posting events so that we can
easily check for duplicates when posting an error.
Reviewed by: Brad Lewis <brad.lewis@delphix.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Don Brady <don.brady@delphix.com>
Closes#10861
use (void) to silence analyzers.
Reviewed-by: Ryan Moeller <ryan@iXsystems.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Toomas Soome <tsoome@me.com>
Closes#10857
This PR adds two new compression types, based on ZStandard:
- zstd: A basic ZStandard compression algorithm Available compression.
Levels for zstd are zstd-1 through zstd-19, where the compression
increases with every level, but speed decreases.
- zstd-fast: A faster version of the ZStandard compression algorithm
zstd-fast is basically a "negative" level of zstd. The compression
decreases with every level, but speed increases.
Available compression levels for zstd-fast:
- zstd-fast-1 through zstd-fast-10
- zstd-fast-20 through zstd-fast-100 (in increments of 10)
- zstd-fast-500 and zstd-fast-1000
For more information check the man page.
Implementation details:
Rather than treat each level of zstd as a different algorithm (as was
done historically with gzip), the block pointer `enum zio_compress`
value is simply zstd for all levels, including zstd-fast, since they all
use the same decompression function.
The compress= property (a 64bit unsigned integer) uses the lower 7 bits
to store the compression algorithm (matching the number of bits used in
a block pointer, as the 8th bit was borrowed for embedded block
pointers). The upper bits are used to store the compression level.
It is necessary to be able to determine what compression level was used
when later reading a block back, so the concept used in LZ4, where the
first 32bits of the on-disk value are the size of the compressed data
(since the allocation is rounded up to the nearest ashift), was
extended, and we store the version of ZSTD and the level as well as the
compressed size. This value is returned when decompressing a block, so
that if the block needs to be recompressed (L2ARC, nop-write, etc), that
the same parameters will be used to result in the matching checksum.
All of the internal ZFS code ( `arc_buf_hdr_t`, `objset_t`,
`zio_prop_t`, etc.) uses the separated _compress and _complevel
variables. Only the properties ZAP contains the combined/bit-shifted
value. The combined value is split when the compression_changed_cb()
callback is called, and sets both objset members (os_compress and
os_complevel).
The userspace tools all use the combined/bit-shifted value.
Additional notes:
zdb can now also decode the ZSTD compression header (flag -Z) and
inspect the size, version and compression level saved in that header.
For each record, if it is ZSTD compressed, the parameters of the decoded
compression header get printed.
ZSTD is included with all current tests and new tests are added
as-needed.
Per-dataset feature flags now get activated when the property is set.
If a compression algorithm requires a feature flag, zfs activates the
feature when the property is set, rather than waiting for the first
block to be born. This is currently only used by zstd but can be
extended as needed.
Portions-Sponsored-By: The FreeBSD Foundation
Co-authored-by: Allan Jude <allanjude@freebsd.org>
Co-authored-by: Brian Behlendorf <behlendorf1@llnl.gov>
Co-authored-by: Sebastian Gottschall <s.gottschall@dd-wrt.com>
Co-authored-by: Kjeld Schouten-Lebbing <kjeld@schouten-lebbing.nl>
Co-authored-by: Michael Niewöhner <foss@mniewoehner.de>
Signed-off-by: Allan Jude <allan@klarasystems.com>
Signed-off-by: Allan Jude <allanjude@freebsd.org>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Sebastian Gottschall <s.gottschall@dd-wrt.com>
Signed-off-by: Kjeld Schouten-Lebbing <kjeld@schouten-lebbing.nl>
Signed-off-by: Michael Niewöhner <foss@mniewoehner.de>
Closes#6247Closes#9024Closes#10277Closes#10278
Mark functions used only in the same translation unit as static. This
only includes functions that do not have a prototype in a header file
either.
Reviewed-by: Ryan Moeller <ryan@iXsystems.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Closes#10470
The strcpy() and sprintf() functions are deprecated on some platforms.
Care is needed to ensure correct size is used. If some platforms
miss snprintf, we can add a #define to sprintf, likewise strlcpy().
The biggest change is adding a size parameter to zfs_id_to_fuidstr().
The various *_impl_get() functions are only used on linux and have
not yet been updated.
Reviewed by: Sean Eric Fagan <sef@ixsystems.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Jorgen Lundman <lundman@lundman.net>
Closes#10400
Make the cityhash code compile into libzfs, in preparation for the new
"zstream" command.
Reviewed-by: Paul Dagnelie <pcd@delphix.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Matthew Ahrens <mahrens@delphix.com>
Closes#10152
Also dprintf_bp() in case BLK_VERIFY_HALT of zfs_blkptr_verify_log()
since dprintf_bp() in zfs_blkptr_verify() will never be executed.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Paul Zuchowski <pzuchowski@datto.com>
Signed-off-by: Justin Keogh <commits@v6y.net>
Closes#10086
__zio_execute() calls zio_taskq_member() to determine if we are running
in a zio interrupt taskq, in which case we may need to switch to
processing this zio in a zio issue taskq. The call to
zio_taskq_member() can become a performance bottleneck when we are
processing a high rate of zio's.
zio_taskq_member() calls taskq_member() on each of the zio interrupt
taskqs, of which there are 21. This is slow because each call to
taskq_member() does tsd_get(taskq_tsd), which on Linux is relatively
slow.
This commit improves the performance of zio_taskq_member() by having it
cache the value of tsd_get(taskq_tsd), reducing the number of those
calls to 1/21th of the current behavior.
In a test case running `zfs send -c >/dev/null` of a filesystem with
small blocks (average 2.5KB/block), zio_taskq_member() was using 6.7% of
one CPU, and with this change it is reduced to 1.3%. Overall time to
perform the `zfs send` reduced by 10% (~150,000 block/sec to ~165,000
blocks/sec).
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Serapheim Dimitropoulos <serapheim@delphix.com>
Reviewed-by: Ryan Moeller <ryan@iXsystems.com>
Reviewed-by: Tony Nguyen <tony.nguyen@delphix.com>
Signed-off-by: Matthew Ahrens <mahrens@delphix.com>
Closes#10070
When "zfs destroy" is run, it completes quickly, and in the background
we locate the blocks to free and free them. This background activity
can be observed with `zpool get freeing` and `zpool wait -t free ...`.
This background activity is processed by a single thread (the spa_sync
thread) which calls zio_free() on each of the blocks to free. With even
modest storage performance, the CPU consumption of zio_free() can be the
performance bottleneck.
Performance of zio_free() can be improved by not actually creating a
zio_t in the common case (non-dedup, non-gang), instead calling
metaslab_free() directly. This avoids the CPU cost of allocating the
zio_t, and more importantly the cost of adding and later removing this
zio_t from the parent zio's child list.
The result is that performance of background freeing more than doubles,
from 0.6 million blocks per second to 1.3 million blocks per second.
Reviewed-by: Paul Dagnelie <pcd@delphix.com>
Reviewed-by: Serapheim Dimitropoulos <serapheim@delphix.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: George Wilson <gwilson@delphix.com>
Signed-off-by: Matthew Ahrens <mahrens@delphix.com>
Closes#10034
zdb -R :b fails due to the indirect block being compressed,
and the 'b' and 'd' flag not working in tandem when specified.
Fix the flag parsing code and create a zfs test for zdb -R
block display. Also fix the zio flags where the dotted notation
for the vdev portion of DVA (i.e. 0.0:offset:length) fails.
Reviewed-by: Ryan Moeller <ryan@iXsystems.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Paul Zuchowski <pzuchowski@datto.com>
Closes#9640Closes#9729
With recent SPL changes there is no longer any need for a per
platform version.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Matt Macy <mmacy@FreeBSD.org>
Closes#9860
This change allows us to align the code dump logic across platforms.
Reviewed-by: Jorgen Lundman <lundman@lundman.net>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Don Brady <don.brady@delphix.com>
Signed-off-by: Matt Macy <mmacy@FreeBSD.org>
Closes#9691
Remove the ASSERTV macro and handle suppressing unused
compiler warnings for variables only in ASSERTs using the
__attribute__((unused)) compiler annotation. The annotation
is understood by both gcc and clang.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Jorgen Lundman <lundman@lundman.net>
Signed-off-by: Matt Macy <mmacy@FreeBSD.org>
Closes#9671
This change modifies some of the infrastructure for enabling the use of
the DTRACE_PROBE* macros, such that we can use tehm in the "spl" module.
Currently, when the DTRACE_PROBE* macros are used, they get expanded to
create new functions, and these dynamically generated functions become
part of the "zfs" module.
Since the "spl" module does not depend on the "zfs" module, the use of
DTRACE_PROBE* in the "spl" module would result in undefined symbols
being used in the "spl" module. Specifically, DTRACE_PROBE* would turn
into a function call, and the function being called would be a symbol
only contained in the "zfs" module; which results in a linker and/or
runtime error.
Thus, this change adds the necessary logic to the "spl" module, to
mirror the tracing functionality available to the "zfs" module. After
this change, we'll have a "trace_zfs.h" header file which defines the
probes available only to the "zfs" module, and a "trace_spl.h" header
file which defines the probes available only to the "spl" module.
Reviewed by: Brad Lewis <brad.lewis@delphix.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Prakash Surya <prakash.surya@delphix.com>
Closes#9525
FreeBSD has its own implementation as do other platforms.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Ryan Moeller <ryan@ixsystems.com>
Signed-off-by: Matt Macy <mmacy@FreeBSD.org>
Closes#9439
Move Linux specific tracing headers and source to platform directories
and update the build system.
Reviewed-by: Allan Jude <allanjude@freebsd.org>
Reviewed-by: Ryan Moeller <ryan@ixsystems.com>
Reviewed by: Brad Lewis <brad.lewis@delphix.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Matt Macy <mmacy@FreeBSD.org>
Closes#9290
Adds ZFS_MODULE_PARAM to abstract module parameter
setting to operating systems other than Linux.
Reviewed-by: Jorgen Lundman <lundman@lundman.net>
Reviewed-by: Igor Kozhukhov <igor@dilos.org>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Matt Macy <mmacy@FreeBSD.org>
Signed-off-by: Ryan Moeller <ryan@ixsystems.com>
Closes#9230
When we check the vdev of the blkptr in zfs_blkptr_verify, we can run
into a race condition where that vdev is temporarily unavailable. This
happens when a device removal operation and the old vdev_t has been
removed from the array, but the new indirect vdev has not yet been
inserted.
We hold the spa_config_lock while doing our sensitive verification.
To ensure that we don't deadlock, we only grab the lock if we don't
have config_writer held. In addition, I had to const the tags of the
refcounts and the spa_config_lock arguments.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Serapheim Dimitropoulos <serapheim@delphix.com>
Signed-off-by: Paul Dagnelie <pcd@delphix.com>
Closes#9112
= Motivation
At Delphix we've seen a lot of customer systems where fragmentation
is over 75% and random writes take a performance hit because a lot
of time is spend on I/Os that update on-disk space accounting metadata.
Specifically, we seen cases where 20% to 40% of sync time is spend
after sync pass 1 and ~30% of the I/Os on the system is spent updating
spacemaps.
The problem is that these pools have existed long enough that we've
touched almost every metaslab at least once, and random writes
scatter frees across all metaslabs every TXG, thus appending to
their spacemaps and resulting in many I/Os. To give an example,
assuming that every VDEV has 200 metaslabs and our writes fit within
a single spacemap block (generally 4K) we have 200 I/Os. Then if we
assume 2 levels of indirection, we need 400 additional I/Os and
since we are talking about metadata for which we keep 2 extra copies
for redundancy we need to triple that number, leading to a total of
1800 I/Os per VDEV every TXG.
We could try and decrease the number of metaslabs so we have less
I/Os per TXG but then each metaslab would cover a wider range on
disk and thus would take more time to be loaded in memory from disk.
In addition, after it's loaded, it's range tree would consume more
memory.
Another idea would be to just increase the spacemap block size
which would allow us to fit more entries within an I/O block
resulting in fewer I/Os per metaslab and a speedup in loading time.
The problem is still that we don't deal with the number of I/Os
going up as the number of metaslabs is increasing and the fact
is that we generally write a lot to a few metaslabs and a little
to the rest of them. Thus, just increasing the block size would
actually waste bandwidth because we won't be utilizing our bigger
block size.
= About this patch
This patch introduces the Log Spacemap project which provides the
solution to the above problem while taking into account all the
aforementioned tradeoffs. The details on how it achieves that can
be found in the references sections below and in the code (see
Big Theory Statement in spa_log_spacemap.c).
Even though the change is fairly constraint within the metaslab
and lower-level SPA codepaths, there is a side-change that is
user-facing. The change is that VDEV IDs from VDEV holes will no
longer be reused. To give some background and reasoning for this,
when a log device is removed and its VDEV structure was replaced
with a hole (or was compacted; if at the end of the vdev array),
its vdev_id could be reused by devices added after that. Now
with the pool-wide space maps recording the vdev ID, this behavior
can cause problems (e.g. is this entry referring to a segment in
the new vdev or the removed log?). Thus, to simplify things the
ID reuse behavior is gone and now vdev IDs for top-level vdevs
are truly unique within a pool.
= Testing
The illumos implementation of this feature has been used internally
for a year and has been in production for ~6 months. For this patch
specifically there don't seem to be any regressions introduced to
ZTS and I have been running zloop for a week without any related
problems.
= Performance Analysis (Linux Specific)
All performance results and analysis for illumos can be found in
the links of the references. Redoing the same experiments in Linux
gave similar results. Below are the specifics of the Linux run.
After the pool reached stable state the percentage of the time
spent in pass 1 per TXG was 64% on average for the stock bits
while the log spacemap bits stayed at 95% during the experiment
(graph: sdimitro.github.io/img/linux-lsm/PercOfSyncInPassOne.png).
Sync times per TXG were 37.6 seconds on average for the stock
bits and 22.7 seconds for the log spacemap bits (related graph:
sdimitro.github.io/img/linux-lsm/SyncTimePerTXG.png). As a result
the log spacemap bits were able to push more TXGs, which is also
the reason why all graphs quantified per TXG have more entries for
the log spacemap bits.
Another interesting aspect in terms of txg syncs is that the stock
bits had 22% of their TXGs reach sync pass 7, 55% reach sync pass 8,
and 20% reach 9. The log space map bits reached sync pass 4 in 79%
of their TXGs, sync pass 7 in 19%, and sync pass 8 at 1%. This
emphasizes the fact that not only we spend less time on metadata
but we also iterate less times to convergence in spa_sync() dirtying
objects.
[related graphs:
stock- sdimitro.github.io/img/linux-lsm/NumberOfPassesPerTXGStock.png
lsm- sdimitro.github.io/img/linux-lsm/NumberOfPassesPerTXGLSM.png]
Finally, the improvement in IOPs that the userland gains from the
change is approximately 40%. There is a consistent win in IOPS as
you can see from the graphs below but the absolute amount of
improvement that the log spacemap gives varies within each minute
interval.
sdimitro.github.io/img/linux-lsm/StockVsLog3Days.png
sdimitro.github.io/img/linux-lsm/StockVsLog10Hours.png
= Porting to Other Platforms
For people that want to port this commit to other platforms below
is a list of ZoL commits that this patch depends on:
Make zdb results for checkpoint tests consistent
db587941c5
Update vdev_is_spacemap_addressable() for new spacemap encoding
419ba59145
Simplify spa_sync by breaking it up to smaller functions
8dc2197b7b
Factor metaslab_load_wait() in metaslab_load()
b194fab0fb
Rename range_tree_verify to range_tree_verify_not_present
df72b8bebe
Change target size of metaslabs from 256GB to 16GB
c853f382db
zdb -L should skip leak detection altogether
21e7cf5da8
vs_alloc can underflow in L2ARC vdevs
7558997d2f
Simplify log vdev removal code
6c926f426a
Get rid of space_map_update() for ms_synced_length
425d3237ee
Introduce auxiliary metaslab histograms
928e8ad47d
Error path in metaslab_load_impl() forgets to drop ms_sync_lock
8eef997679
= References
Background, Motivation, and Internals of the Feature
- OpenZFS 2017 Presentation:
youtu.be/jj2IxRkl5bQ
- Slides:
slideshare.net/SerapheimNikolaosDim/zfs-log-spacemaps-project
Flushing Algorithm Internals & Performance Results
(Illumos Specific)
- Blogpost:
sdimitro.github.io/post/zfs-lsm-flushing/
- OpenZFS 2018 Presentation:
youtu.be/x6D2dHRjkxw
- Slides:
slideshare.net/SerapheimNikolaosDim/zfs-log-spacemap-flushing-algorithm
Upstream Delphix Issues:
DLPX-51539, DLPX-59659, DLPX-57783, DLPX-61438, DLPX-41227, DLPX-59320
DLPX-63385
Reviewed-by: Sean Eric Fagan <sef@ixsystems.com>
Reviewed-by: Matt Ahrens <matt@delphix.com>
Reviewed-by: George Wilson <gwilson@delphix.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Serapheim Dimitropoulos <serapheim@delphix.com>
Closes#8442
After device removal, performing nopwrites on a dmu_sync-ed block
will result in a panic. This panic can show up in two ways:
1. an attempt to issue an IOCTL in vdev_indirect_io_start()
2. a failed comparison of zio->io_bp and zio->io_bp_orig in
zio_done()
To resolve both of these panics, nopwrites of blocks on indirect
vdevs should be ignored and new allocations should be performed on
concrete vdevs.
Reviewed-by: Igor Kozhukhov <igor@dilos.org>
Reviewed-by: Pavel Zakharov <pavel.zakharov@delphix.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Don Brady <don.brady@delphix.com>
Signed-off-by: George Wilson <gwilson@delphix.com>
Closes#8957
With the addition of BP_EMBEDDED_TYPE_REDACTED in 30af21b0 a couple of
codepaths make wrong assumptions and could potentially result in errors.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Chris Dunlop <chris@onthe.net.au>
Reviewed-by: Paul Dagnelie <pcd@delphix.com>
Signed-off-by: loli10K <ezomori.nozomu@gmail.com>
Closes#8951
The logic to handle strong checksum collisions where the data doesn't
match is incorrect. It is not clearing the dedup bit of the blkptr,
which can cause a panic later in zio_ddt_free() due to the dedup table
not matching what is in the blkptr.
Reviewed-by: Tom Caputi <tcaputi@datto.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Matthew Ahrens <mahrens@delphix.com>
External-issue: DLPX-48097
Closes#8936
If dedup is in use, the `dedupditto` property can be set, causing ZFS to
keep an extra copy of data that is referenced many times (>100x). The
idea was that this data is more important than other data and thus we
want to be really sure that it is not lost if the disk experiences a
small amount of random corruption.
ZFS (and system administrators) rely on the pool-level redundancy to
protect their data (e.g. mirroring or RAIDZ). Since the user/sysadmin
doesn't have control over what data will be offered extra redundancy by
dedupditto, this extra redundancy is not very useful. The bulk of the
data is still vulnerable to loss based on the pool-level redundancy.
For example, if particle strikes corrupt 0.1% of blocks, you will either
be saved by mirror/raidz, or you will be sad. This is true even if
dedupditto saved another 0.01% of blocks from being corrupted.
Therefore, the dedupditto functionality is rarely enabled (i.e. the
property is rarely set), and it fulfills its promise of increased
redundancy even more rarely.
Additionally, this feature does not work as advertised (on existing
releases), because scrub/resilver did not repair the extra (dedupditto)
copy (see https://github.com/zfsonlinux/zfs/pull/8270).
In summary, this seldom-used feature doesn't work, and even if it did it
wouldn't provide useful data protection. It has a non-trivial
maintenance burden (again see https://github.com/zfsonlinux/zfs/pull/8270).
We should remove the dedupditto functionality. For backwards
compatibility with the existing CLI, "zpool set dedupditto" will still
"succeed" (exit code zero), but won't have any effect. For backwards
compatibility with existing pools that had dedupditto enabled at some
point, the code will still be able to understand dedupditto blocks and
free them when appropriate. However, ZFS won't write any new dedupditto
blocks.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Igor Kozhukhov <igor@dilos.org>
Reviewed-by: Alek Pinchuk <apinchuk@datto.com>
Issue #8270Closes#8310
Redacted send/receive allows users to send subsets of their data to
a target system. One possible use case for this feature is to not
transmit sensitive information to a data warehousing, test/dev, or
analytics environment. Another is to save space by not replicating
unimportant data within a given dataset, for example in backup tools
like zrepl.
Redacted send/receive is a three-stage process. First, a clone (or
clones) is made of the snapshot to be sent to the target. In this
clone (or clones), all unnecessary or unwanted data is removed or
modified. This clone is then snapshotted to create the "redaction
snapshot" (or snapshots). Second, the new zfs redact command is used
to create a redaction bookmark. The redaction bookmark stores the
list of blocks in a snapshot that were modified by the redaction
snapshot(s). Finally, the redaction bookmark is passed as a parameter
to zfs send. When sending to the snapshot that was redacted, the
redaction bookmark is used to filter out blocks that contain sensitive
or unwanted information, and those blocks are not included in the send
stream. When sending from the redaction bookmark, the blocks it
contains are considered as candidate blocks in addition to those
blocks in the destination snapshot that were modified since the
creation_txg of the redaction bookmark. This step is necessary to
allow the target to rehydrate data in the case where some blocks are
accidentally or unnecessarily modified in the redaction snapshot.
The changes to bookmarks to enable fast space estimation involve
adding deadlists to bookmarks. There is also logic to manage the
life cycles of these deadlists.
The new size estimation process operates in cases where previously
an accurate estimate could not be provided. In those cases, a send
is performed where no data blocks are read, reducing the runtime
significantly and providing a byte-accurate size estimate.
Reviewed-by: Dan Kimmel <dan.kimmel@delphix.com>
Reviewed-by: Matt Ahrens <mahrens@delphix.com>
Reviewed-by: Prashanth Sreenivasa <pks@delphix.com>
Reviewed-by: John Kennedy <john.kennedy@delphix.com>
Reviewed-by: George Wilson <george.wilson@delphix.com>
Reviewed-by: Chris Williamson <chris.williamson@delphix.com>
Reviewed-by: Pavel Zhakarov <pavel.zakharov@delphix.com>
Reviewed-by: Sebastien Roy <sebastien.roy@delphix.com>
Reviewed-by: Prakash Surya <prakash.surya@delphix.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Paul Dagnelie <pcd@delphix.com>
Closes#7958
Starting in sync pass 5 (zfs_sync_pass_dont_compress), we disable
compression (including of metadata). Ostensibly this helps the sync
passes to converge (i.e. for a sync pass to not need to allocate
anything because it is 100% overwrites).
However, in practice it increases the average number of sync passes,
because when we turn compression off, a lot of block's size will change
and thus we have to re-allocate (not overwrite) them. It also increases
the number of 128KB allocations (e.g. for indirect blocks and spacemaps)
because these will not be compressed. The 128K allocations are
especially detrimental to performance on highly fragmented systems,
which may have very few free segments of this size, and may need to load
new metaslabs to satisfy 128K allocations.
We should increase zfs_sync_pass_dont_compress. In practice on a highly
fragmented system we see a few 5-pass txg's, a tiny number of 6-pass
txg's, and no txg's with more than 6 passes.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Richard Elling <Richard.Elling@RichardElling.com>
Reviewed by: Pavel Zakharov <pavel.zakharov@delphix.com>
Reviewed-by: Serapheim Dimitropoulos <serapheim@delphix.com>
Reviewed-by: George Wilson <george.wilson@delphix.com>
Signed-off-by: Matthew Ahrens <mahrens@delphix.com>
External-issue: DLPX-63431
Closes#8892
Scatter ABD's are allocated from a number of pages. In contrast to
linear ABD's, these pages are disjoint in the kernel's virtual address
space, so they can't be accessed as a contiguous buffer. Therefore
routines that need a linear buffer (e.g. abd_borrow_buf() and friends)
must allocate a separate linear buffer (with zio_buf_alloc()), and copy
the contents of the pages to/from the linear buffer. This can have a
measurable performance overhead on some workloads.
https://github.com/zfsonlinux/zfs/commit/87c25d567fb7969b44c7d8af63990e
("abd_alloc should use scatter for >1K allocations") increased the use
of scatter ABD's, specifically switching 1.5K through 4K (inclusive)
buffers from linear to scatter. For workloads that access blocks whose
compressed sizes are in this range, that commit introduced an additional
copy into the read code path. For example, the
sequential_reads_arc_cached tests in the test suite were reduced by
around 5% (this is doing reads of 8K-logical blocks, compressed to 3K,
which are cached in the ARC).
This commit treats single-chunk scattered buffers as linear buffers,
because they are contiguous in the kernel's virtual address space.
All single-page (4K) ABD's can be represented this way. Some multi-page
ABD's can also be represented this way, if we were able to allocate a
single "chunk" (higher-order "page" which represents a power-of-2 series
of physically-contiguous pages). This is often the case for 2-page (8K)
ABD's.
Representing a single-entry scatter ABD as a linear ABD has the
performance advantage of avoiding the copy (and allocation) in
abd_borrow_buf_copy / abd_return_buf_copy. A performance increase of
around 5% has been observed for ARC-cached reads (of small blocks which
can take advantage of this), fixing the regression introduced by
87c25d567.
Note that this optimization is only possible because all physical memory
is always mapped into the kernel's address space. This is not the case
for HIGHMEM pages, so the optimization can not be made on 32-bit
systems.
Reviewed-by: Chunwei Chen <tuxoko@gmail.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Matthew Ahrens <mahrens@delphix.com>
Closes#8580
There are several places where we use zfs_dbgmsg and %p to
print pointers. In the Linux kernel, these values obfuscated
to prevent information leaks which means the pointers aren't
very useful for debugging crash dumps. We decided to restrict
the permissions of dbgmsg (and some other kstats while we were
at it) and print pointers with %px in zfs_dbgmsg as well as
spl_dumpstack
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: John Gallagher <john.gallagher@delphix.com>
Signed-off-by: sara hartse <sara.hartse@delphix.com>
Closes#8467Closes#8476
UNMAP/TRIM support is a frequently-requested feature to help
prevent performance from degrading on SSDs and on various other
SAN-like storage back-ends. By issuing UNMAP/TRIM commands for
sectors which are no longer allocated the underlying device can
often more efficiently manage itself.
This TRIM implementation is modeled on the `zpool initialize`
feature which writes a pattern to all unallocated space in the
pool. The new `zpool trim` command uses the same vdev_xlate()
code to calculate what sectors are unallocated, the same per-
vdev TRIM thread model and locking, and the same basic CLI for
a consistent user experience. The core difference is that
instead of writing a pattern it will issue UNMAP/TRIM commands
for those extents.
The zio pipeline was updated to accommodate this by adding a new
ZIO_TYPE_TRIM type and associated spa taskq. This new type makes
is straight forward to add the platform specific TRIM/UNMAP calls
to vdev_disk.c and vdev_file.c. These new ZIO_TYPE_TRIM zios are
handled largely the same way as ZIO_TYPE_READs or ZIO_TYPE_WRITEs.
This makes it possible to largely avoid changing the pipieline,
one exception is that TRIM zio's may exceed the 16M block size
limit since they contain no data.
In addition to the manual `zpool trim` command, a background
automatic TRIM was added and is controlled by the 'autotrim'
property. It relies on the exact same infrastructure as the
manual TRIM. However, instead of relying on the extents in a
metaslab's ms_allocatable range tree, a ms_trim tree is kept
per metaslab. When 'autotrim=on', ranges added back to the
ms_allocatable tree are also added to the ms_free tree. The
ms_free tree is then periodically consumed by an autotrim
thread which systematically walks a top level vdev's metaslabs.
Since the automatic TRIM will skip ranges it considers too small
there is value in occasionally running a full `zpool trim`. This
may occur when the freed blocks are small and not enough time
was allowed to aggregate them. An automatic TRIM and a manual
`zpool trim` may be run concurrently, in which case the automatic
TRIM will yield to the manual TRIM.
Reviewed-by: Jorgen Lundman <lundman@lundman.net>
Reviewed-by: Tim Chase <tim@chase2k.com>
Reviewed-by: Matt Ahrens <mahrens@delphix.com>
Reviewed-by: George Wilson <george.wilson@delphix.com>
Reviewed-by: Serapheim Dimitropoulos <serapheim@delphix.com>
Contributions-by: Saso Kiselkov <saso.kiselkov@nexenta.com>
Contributions-by: Tim Chase <tim@chase2k.com>
Contributions-by: Chunwei Chen <tuxoko@gmail.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#8419Closes#598
The number of IO and checksum events should match the number of errors
seen in zpool status. Previously there was a mismatch between the
two counts because zpool status would only count unrecovered errors,
while zpool events would get an event for *all* errors (recovered or
not). This lead to situations where disks could be faulted for
"too many errors", while at the same time showing zero errors in zpool
status.
This fixes the zpool status error counters to increment at the same
times we post the error events.
Reviewed-by: Tom Caputi <tcaputi@datto.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Olaf Faaland <faaland1@llnl.gov>
Signed-off-by: Tony Hutter <hutter2@llnl.gov>
Closes#4851Closes#7817
If we hit the (NSEC_TO_TICK(diff) == 0) condition in
zio_delay_interrupt, zio_interrupt is never called and the
zio does not progress.
Reviewed by: Matt Ahrens <mahrens@delphix.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: George Melikov <mail@gmelikov.ru>
Signed-off-by: sara hartse <sara.hartse@delphix.com>
Closes#8404
Add the zio_deadman_log_all tunable to print all zios in
zio_deadman_impl(). Also, in all cases, display the depth of the
zio relative to the original parent zio. This is meant to be used by
developers to gain diagnostic information for hangs which don't involve
fully set-up zio trees or are otherwise stuck or hung in an early stage.
Reviewed-by: Olaf Faaland <faaland1@llnl.gov>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: loli10K <ezomori.nozomu@gmail.com>
Signed-off-by: Tim Chase <tim@chase2k.com>
Closes#8362
Some minor spelling mistakes and typos. No functional changes.
Reviewed-by: Neal Gompa <ngompa@datto.com>
Reviewed by: Matt Ahrens <mahrens@delphix.com>
Reviewed-by: Giuseppe Di Natale <guss80@gmail.com>
Reviewed-by: bunder2015 <omfgbunder@gmail.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#8272
This patch adds a new slow I/Os (-s) column to zpool status to show the
number of VDEV slow I/Os. This is the number of I/Os that didn't
complete in zio_slow_io_ms milliseconds. It also adds a new parsable
(-p) flag to display exact values.
NAME STATE READ WRITE CKSUM SLOW
testpool ONLINE 0 0 0 -
mirror-0 ONLINE 0 0 0 -
loop0 ONLINE 0 0 0 20
loop1 ONLINE 0 0 0 0
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Signed-off-by: Tony Hutter <hutter2@llnl.gov>
Closes#7756Closes#6885
Recent changes in the Linux kernel made it necessary to prefix
the refcount_add() function with zfs_ due to a name collision.
To bring the other functions in line with that and to avoid future
collisions, prefix the other refcount functions as well.
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Tim Schumacher <timschumi@gmx.de>
Closes#7963
Allocation Classes add the ability to have allocation classes in a
pool that are dedicated to serving specific block categories, such
as DDT data, metadata, and small file blocks. A pool can opt-in to
this feature by adding a 'special' or 'dedup' top-level VDEV.
Reviewed by: Pavel Zakharov <pavel.zakharov@delphix.com>
Reviewed-by: Richard Laager <rlaager@wiktel.com>
Reviewed-by: Alek Pinchuk <apinchuk@datto.com>
Reviewed-by: Håkan Johansson <f96hajo@chalmers.se>
Reviewed-by: Andreas Dilger <andreas.dilger@chamcloud.com>
Reviewed-by: DHE <git@dehacked.net>
Reviewed-by: Richard Elling <Richard.Elling@RichardElling.com>
Reviewed-by: Gregor Kopka <gregor@kopka.net>
Reviewed-by: Kash Pande <kash@tripleback.net>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Matthew Ahrens <mahrens@delphix.com>
Signed-off-by: Don Brady <don.brady@delphix.com>
Closes#5182
Assertion failed in arc_buf_destroy() when concurrently reading
block with checksum error.
Porting notes:
* The ability to zinject decompression errors has been added, but
this only works at the zio_decompress() level, where we have all
of the info we need to match against the user's zinject options.
* The decompress_fault test has been added to test the new zinject
functionality
* We attempted to set zio_decompress_fail_fraction to (1 << 18) in
ztest for further test coverage. Although this did uncover a few
low priority issues, this unfortuantely also causes ztest to
ASSERT in many locations where the code is working correctly since
it is designed to fail on IO errors. Developers can manually set
this variable with the '-o' option to find and debug issues.
Authored by: Matt Ahrens <mahrens@delphix.com>
Reviewed by: George Wilson <george.wilson@delphix.com>
Reviewed by: Paul Dagnelie <pcd@delphix.com>
Reviewed by: Pavel Zakharov <pavel.zakharov@delphix.com>
Reviewed by: Brian Behlendorf <behlendorf1@llnl.gov>
Approved by: Matt Ahrens <mahrens@delphix.com>
Ported-by: Tom Caputi <tcaputi@datto.com>
OpenZFS-issue: https://illumos.org/issues/9403
OpenZFS-commit: https://github.com/openzfs/openzfs/commit/fa98e487a9Closes#7822
When doing a read from disk, ZFS creates 3 ZIO's: a zio_null(), the
logical zio_read(), and then a physical zio. Currently, each of these
results in a separate taskq_dispatch(zio_execute).
On high-read-iops workloads, this causes a significant performance
impact. By processing all 3 ZIO's in a single taskq entry, we reduce the
overhead on taskq locking and context switching. We accomplish this by
allowing zio_done() to return a "next zio to execute" to zio_execute().
This results in a ~12% performance increase for random reads, from
96,000 iops to 108,000 iops (with recordsize=8k, on SSD's).
Reviewed by: Pavel Zakharov <pavel.zakharov@delphix.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed by: George Wilson <george.wilson@delphix.com>
Signed-off-by: Matthew Ahrens <mahrens@delphix.com>
External-issue: DLPX-59292
Closes#7736
Overview
========
We parallelize the allocation process by creating the concept of
"allocators". There are a certain number of allocators per metaslab
group, defined by the value of a tunable at pool open time. Each
allocator for a given metaslab group has up to 2 active metaslabs; one
"primary", and one "secondary". The primary and secondary weight mean
the same thing they did in in the pre-allocator world; primary metaslabs
are used for most allocations, secondary metaslabs are used for ditto
blocks being allocated in the same metaslab group. There is also the
CLAIM weight, which has been separated out from the other weights, but
that is less important to understanding the patch. The active metaslabs
for each allocator are moved from their normal place in the metaslab
tree for the group to the back of the tree. This way, they will not be
selected for use by other allocators searching for new metaslabs unless
all the passive metaslabs are unsuitable for allocations. If that does
happen, the allocators will "steal" from each other to ensure that IOs
don't fail until there is truly no space left to perform allocations.
In addition, the alloc queue for each metaslab group has been broken
into a separate queue for each allocator. We don't want to dramatically
increase the number of inflight IOs on low-end systems, because it can
significantly increase txg times. On the other hand, we want to ensure
that there are enough IOs for each allocator to allow for good
coalescing before sending the IOs to the disk. As a result, we take a
compromise path; each allocator's alloc queue max depth starts at a
certain value for every txg. Every time an IO completes, we increase the
max depth. This should hopefully provide a good balance between the two
failure modes, while not dramatically increasing complexity.
We also parallelize the spa_alloc_tree and spa_alloc_lock, which cause
very similar contention when selecting IOs to allocate. This
parallelization uses the same allocator scheme as metaslab selection.
Performance Results
===================
Performance improvements from this change can vary significantly based
on the number of CPUs in the system, whether or not the system has a
NUMA architecture, the speed of the drives, the values for the various
tunables, and the workload being performed. For an fio async sequential
write workload on a 24 core NUMA system with 256 GB of RAM and 8 128 GB
SSDs, there is a roughly 25% performance improvement.
Future Work
===========
Analysis of the performance of the system with this patch applied shows
that a significant new bottleneck is the vdev disk queues, which also
need to be parallelized. Prototyping of this change has occurred, and
there was a performance improvement, but more work needs to be done
before its stability has been verified and it is ready to be upstreamed.
Authored by: Paul Dagnelie <pcd@delphix.com>
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Reviewed by: George Wilson <george.wilson@delphix.com>
Reviewed by: Serapheim Dimitropoulos <serapheim.dimitro@delphix.com>
Reviewed by: Alexander Motin <mav@FreeBSD.org>
Reviewed by: Brian Behlendorf <behlendorf1@llnl.gov>
Approved by: Gordon Ross <gwr@nexenta.com>
Ported-by: Paul Dagnelie <pcd@delphix.com>
Signed-off-by: Paul Dagnelie <pcd@delphix.com>
Porting Notes:
* Fix reservation test failures by increasing tolerance.
OpenZFS-issue: https://illumos.org/issues/9112
OpenZFS-commit: https://github.com/openzfs/openzfs/commit/3f3cc3c3Closes#7682
Details about the motivation of this feature and its usage can
be found in this blogpost:
https://sdimitro.github.io/post/zpool-checkpoint/
A lightning talk of this feature can be found here:
https://www.youtube.com/watch?v=fPQA8K40jAM
Implementation details can be found in big block comment of
spa_checkpoint.c
Side-changes that are relevant to this commit but not explained
elsewhere:
* renames members of "struct metaslab trees to be shorter without
losing meaning
* space_map_{alloc,truncate}() accept a block size as a
parameter. The reason is that in the current state all space
maps that we allocate through the DMU use a global tunable
(space_map_blksz) which defauls to 4KB. This is ok for metaslab
space maps in terms of bandwirdth since they are scattered all
over the disk. But for other space maps this default is probably
not what we want. Examples are device removal's vdev_obsolete_sm
or vdev_chedkpoint_sm from this review. Both of these have a
1:1 relationship with each vdev and could benefit from a bigger
block size.
Porting notes:
* The part of dsl_scan_sync() which handles async destroys has
been moved into the new dsl_process_async_destroys() function.
* Remove "VERIFY(!(flags & FWRITE))" in "kernel.c" so zhack can write
to block device backed pools.
* ZTS:
* Fix get_txg() in zpool_sync_001_pos due to "checkpoint_txg".
* Don't use large dd block sizes on /dev/urandom under Linux in
checkpoint_capacity.
* Adopt Delphix-OS's setting of 4 (spa_asize_inflation =
SPA_DVAS_PER_BP + 1) for the checkpoint_capacity test to speed
its attempts to fill the pool
* Create the base and nested pools with sync=disabled to speed up
the "setup" phase.
* Clear labels in test pool between checkpoint tests to avoid
duplicate pool issues.
* The import_rewind_device_replaced test has been marked as "known
to fail" for the reasons listed in its DISCLAIMER.
* New module parameters:
zfs_spa_discard_memory_limit,
zfs_remove_max_bytes_pause (not documented - debugging only)
vdev_max_ms_count (formerly metaslabs_per_vdev)
vdev_min_ms_count
Authored by: Serapheim Dimitropoulos <serapheim.dimitro@delphix.com>
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Reviewed by: John Kennedy <john.kennedy@delphix.com>
Reviewed by: Dan Kimmel <dan.kimmel@delphix.com>
Reviewed by: Brian Behlendorf <behlendorf1@llnl.gov>
Approved by: Richard Lowe <richlowe@richlowe.net>
Ported-by: Tim Chase <tim@chase2k.com>
Signed-off-by: Tim Chase <tim@chase2k.com>
OpenZFS-issue: https://illumos.org/issues/9166
OpenZFS-commit: https://github.com/openzfs/openzfs/commit/7159fdb8Closes#7570
Minimal changes required to integrate the SPL sources in to the
ZFS repository build infrastructure and packaging.
Build system and packaging:
* Renamed SPL_* autoconf m4 macros to ZFS_*.
* Removed redundant SPL_* autoconf m4 macros.
* Updated the RPM spec files to remove SPL package dependency.
* The zfs package obsoletes the spl package, and the zfs-kmod
package obsoletes the spl-kmod package.
* The zfs-kmod-devel* packages were updated to add compatibility
symlinks under /usr/src/spl-x.y.z until all dependent packages
can be updated. They will be removed in a future release.
* Updated copy-builtin script for in-kernel builds.
* Updated DKMS package to include the spl.ko.
* Updated stale AUTHORS file to include all contributors.
* Updated stale COPYRIGHT and included the SPL as an exception.
* Renamed README.markdown to README.md
* Renamed OPENSOLARIS.LICENSE to LICENSE.
* Renamed DISCLAIMER to NOTICE.
Required code changes:
* Removed redundant HAVE_SPL macro.
* Removed _BOOT from nvpairs since it doesn't apply for Linux.
* Initial header cleanup (removal of empty headers, refactoring).
* Remove SPL repository clone/build from zimport.sh.
* Use of DEFINE_RATELIMIT_STATE and DEFINE_SPINLOCK removed due
to build issues when forcing C99 compilation.
* Replaced legacy ACCESS_ONCE with READ_ONCE.
* Include needed headers for `current` and `EXPORT_SYMBOL`.
Reviewed-by: Tony Hutter <hutter2@llnl.gov>
Reviewed-by: Olaf Faaland <faaland1@llnl.gov>
Reviewed-by: Matthew Ahrens <mahrens@delphix.com>
Reviewed-by: Pavel Zakharov <pavel.zakharov@delphix.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
TEST_ZIMPORT_SKIP="yes"
Closes#7556
Some work has been done lately to improve the debugability of the ZFS pool
load (and import) process. This includes:
7638 Refactor spa_load_impl into several functions
8961 SPA load/import should tell us why it failed
7277 zdb should be able to print zfs_dbgmsg's
To iterate on top of that, there's a few changes that were made to make the
import process more resilient and crash free. One of the first tasks during the
pool load process is to parse a config provided from userland that describes
what devices the pool is composed of. A vdev tree is generated from that config,
and then all the vdevs are opened.
The Meta Object Set (MOS) of the pool is accessed, and several metadata objects
that are necessary to load the pool are read. The exact configuration of the
pool is also stored inside the MOS. Since the configuration provided from
userland is external and might not accurately describe the vdev tree
of the pool at the txg that is being loaded, it cannot be relied upon to safely
operate the pool. For that reason, the configuration in the MOS is read early
on. In the past, the two configurations were compared together and if there was
a mismatch then the load process was aborted and an error was returned.
The latter was a good way to ensure a pool does not get corrupted, however it
made the pool load process needlessly fragile in cases where the vdev
configuration changed or the userland configuration was outdated. Since the MOS
is stored in 3 copies, the configuration provided by userland doesn't have to be
perfect in order to read its contents. Hence, a new approach has been adopted:
The pool is first opened with the untrusted userland configuration just so that
the real configuration can be read from the MOS. The trusted MOS configuration
is then used to generate a new vdev tree and the pool is re-opened.
When the pool is opened with an untrusted configuration, writes are disabled
to avoid accidentally damaging it. During reads, some sanity checks are
performed on block pointers to see if each DVA points to a known vdev;
when the configuration is untrusted, instead of panicking the system if those
checks fail we simply avoid issuing reads to the invalid DVAs.
This new two-step pool load process now allows rewinding pools accross
vdev tree changes such as device replacement, addition, etc. Loading a pool
from an external config file in a clustering environment also becomes much
safer now since the pool will import even if the config is outdated and didn't,
for instance, register a recent device addition.
With this code in place, it became relatively easy to implement a
long-sought-after feature: the ability to import a pool with missing top level
(i.e. non-redundant) devices. Note that since this almost guarantees some loss
of data, this feature is for now restricted to a read-only import.
Porting notes (ZTS):
* Fix 'make dist' target in zpool_import
* The maximum path length allowed by tar is 99 characters. Several
of the new test cases exceeded this limit resulting in them not
being included in the tarball. Shorten the names slightly.
* Set/get tunables using accessor functions.
* Get last synced txg via the "zfs_txg_history" mechanism.
* Clear zinject handlers in cleanup for import_cache_device_replaced
and import_rewind_device_replaced in order that the zpool can be
exported if there is an error.
* Increase FILESIZE to 8G in zfs-test.sh to allow for a larger
ext4 file system to be created on ZFS_DISK2. Also, there's
no need to partition ZFS_DISK2 at all. The partitioning had
already been disabled for multipath devices. Among other things,
the partitioning steals some space from the ext4 file system,
makes it difficult to accurately calculate the paramters to
parted and can make some of the tests fail.
* Increase FS_SIZE and FILE_SIZE in the zpool_import test
configuration now that FILESIZE is larger.
* Write more data in order that device evacuation take lonnger in
a couple tests.
* Use mkdir -p to avoid errors when the directory already exists.
* Remove use of sudo in import_rewind_config_changed.
Authored by: Pavel Zakharov <pavel.zakharov@delphix.com>
Reviewed by: George Wilson <george.wilson@delphix.com>
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Reviewed by: Andrew Stormont <andyjstormont@gmail.com>
Approved by: Hans Rosenfeld <rosenfeld@grumpf.hope-2000.org>
Ported-by: Tim Chase <tim@chase2k.com>
Signed-off-by: Tim Chase <tim@chase2k.com>
OpenZFS-issue: https://illumos.org/issues/9075
OpenZFS-commit: https://github.com/openzfs/openzfs/commit/619c0123Closes#7459
This patch adds the ability for zinject to trigger decryption
and authentication faults in the ZIO and ARC layers. This
functionality is exposed via the new "decrypt" error type, which
may be provided for "data" object types.
This patch also refactors some of the core encryption / decryption
functions so that they have consistent prototypes, handle errors
consistently, and do not have unused arguments.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Tom Caputi <tcaputi@datto.com>
Closes#7474
We should use zfs_dbgmsg instead of spa_dbgmsg. Or at least,
metaslab_condense() should call zfs_dbgmsg because it's important and
rare enough to always log. It's possible that the message in
zio_dva_allocate() would be too high-frequency for zfs_dbgmsg.
Authored by: Matthew Ahrens <mahrens@delphix.com>
Reviewed by: Serapheim Dimitropoulos <serapheim.dimitro@delphix.com>
Reviewed by: Pavel Zakharov <pavel.zakharov@delphix.com>
Reviewed by: George Wilson <george.wilson@delphix.com>
Reviewed by: Richard Elling <Richard.Elling@RichardElling.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Approved by: Richard Lowe <richlowe@richlowe.net>
Ported-by: Giuseppe Di Natale <dinatale2@llnl.gov>
Patch Notes:
* Removed ZFS_DEBUG_SPA from zfs-module-parameters.5
OpenZFS-issue: https://www.illumos.org/issues/9236
OpenZFS-commit: https://github.com/openzfs/openzfs/commit/cfaba7f668Closes#7467
Mirrors are supposed to provide redundancy in the face of whole-disk
failure and silent damage (e.g. some data on disk is not right, but ZFS
hasn't detected the whole device as being broken). However, the current
device removal implementation bypasses some of the mirror's redundancy.
Note that in no case is incorrect data returned, but we might get a
checksum error when we should have been able to find the right data.
There are two underlying problems:
1. When we remove a mirror device, we only read one side of the mirror.
Since we can't verify the checksum, this side may be silently bad, but
the good data is on the other side of the mirror (which we didn't read).
This can cause the removal to "bake in" the busted data – all copies of
the data in the new location are the same, busted version, while we left
the good version behind.
The fix for this is to read and copy both sides of the mirror. If the
old and new vdevs are mirrors, we will read both sides of the old
mirror, and write each copy to the corresponding side of the new mirror.
(If the old and new vdevs have a different number of children, we will
do this as best as possible.) Even though we aren't verifying checksums,
this ensures that as long as there's a good copy of the data, we'll have
a good copy after the removal, even if there's silent damage to one side
of the mirror. If we're removing a mirror that has some silent damage,
we'll have exactly the same damage in the new location (assuming that
the new location is also a mirror).
2. When we read from an indirect vdev that points to a mirror vdev, we
only consider one copy of the data. This can lead to reduced effective
redundancy, because we might read a bad copy of the data from one side
of the mirror, and not retry the other, good side of the mirror.
Note that the problem is not with the removal process, but rather after
the removal has completed (having copied correct data to both sides of
the mirror), if one side of the new mirror is silently damaged, we
encounter the problem when reading the relocated data via the indirect
vdev. Also note that the problem doesn't occur when ZFS knows that one
side of the mirror is bad, e.g. when a disk entirely fails or is
offlined.
The impact is that reads (from indirect vdevs that point to mirrors) may
return a checksum error even though the good data exists on one side of
the mirror, and scrub doesn't repair all data on the mirror (if some of
it is pointed to via an indirect vdev).
The fix for this is complicated by "split blocks" - one logical block
may be split into two (or more) pieces with each piece moved to a
different new location. In this case we need to read all versions of
each split (one from each side of the mirror), and figure out which
combination of versions results in the correct checksum, and then repair
the incorrect versions.
This ensures that we supply the same redundancy whether you use device
removal or not. For example, if a mirror has small silent errors on all
of its children, we can still reconstruct the correct data, as long as
those errors are at sufficiently-separated offsets (specifically,
separated by the largest block size - default of 128KB, but up to 16MB).
Porting notes:
* A new indirect vdev check was moved from dsl_scan_needs_resilver_cb()
to dsl_scan_needs_resilver(), which was added to ZoL as part of the
sequential scrub work.
* Passed NULL for zfs_ereport_post_checksum()'s zbookmark_phys_t
parameter. The extra parameter is unique to ZoL.
* When posting indirect checksum errors the ABD can be passed directly,
zfs_ereport_post_checksum() is not yet ABD-aware in OpenZFS.
Authored by: Matthew Ahrens <mahrens@delphix.com>
Reviewed by: Tim Chase <tim@chase2k.com>
Reviewed by: Brian Behlendorf <behlendorf1@llnl.gov>
Ported-by: Tim Chase <tim@chase2k.com>
OpenZFS-issue: https://illumos.org/issues/9290
OpenZFS-commit: https://github.com/openzfs/openzfs/pull/591Closes#6900
OpenZFS 7614 - zfs device evacuation/removal
OpenZFS 9064 - remove_mirror should wait for device removal to complete
This project allows top-level vdevs to be removed from the storage pool
with "zpool remove", reducing the total amount of storage in the pool.
This operation copies all allocated regions of the device to be removed
onto other devices, recording the mapping from old to new location.
After the removal is complete, read and free operations to the removed
(now "indirect") vdev must be remapped and performed at the new location
on disk. The indirect mapping table is kept in memory whenever the pool
is loaded, so there is minimal performance overhead when doing operations
on the indirect vdev.
The size of the in-memory mapping table will be reduced when its entries
become "obsolete" because they are no longer used by any block pointers
in the pool. An entry becomes obsolete when all the blocks that use
it are freed. An entry can also become obsolete when all the snapshots
that reference it are deleted, and the block pointers that reference it
have been "remapped" in all filesystems/zvols (and clones). Whenever an
indirect block is written, all the block pointers in it will be "remapped"
to their new (concrete) locations if possible. This process can be
accelerated by using the "zfs remap" command to proactively rewrite all
indirect blocks that reference indirect (removed) vdevs.
Note that when a device is removed, we do not verify the checksum of
the data that is copied. This makes the process much faster, but if it
were used on redundant vdevs (i.e. mirror or raidz vdevs), it would be
possible to copy the wrong data, when we have the correct data on e.g.
the other side of the mirror.
At the moment, only mirrors and simple top-level vdevs can be removed
and no removal is allowed if any of the top-level vdevs are raidz.
Porting Notes:
* Avoid zero-sized kmem_alloc() in vdev_compact_children().
The device evacuation code adds a dependency that
vdev_compact_children() be able to properly empty the vdev_child
array by setting it to NULL and zeroing vdev_children. Under Linux,
kmem_alloc() and related functions return a sentinel pointer rather
than NULL for zero-sized allocations.
* Remove comment regarding "mpt" driver where zfs_remove_max_segment
is initialized to SPA_MAXBLOCKSIZE.
Change zfs_condense_indirect_commit_entry_delay_ticks to
zfs_condense_indirect_commit_entry_delay_ms for consistency with
most other tunables in which delays are specified in ms.
* ZTS changes:
Use set_tunable rather than mdb
Use zpool sync as appropriate
Use sync_pool instead of sync
Kill jobs during test_removal_with_operation to allow unmount/export
Don't add non-disk names such as "mirror" or "raidz" to $DISKS
Use $TEST_BASE_DIR instead of /tmp
Increase HZ from 100 to 1000 which is more common on Linux
removal_multiple_indirection.ksh
Reduce iterations in order to not time out on the code
coverage builders.
removal_resume_export:
Functionally, the test case is correct but there exists a race
where the kernel thread hasn't been fully started yet and is
not visible. Wait for up to 1 second for the removal thread
to be started before giving up on it. Also, increase the
amount of data copied in order that the removal not finish
before the export has a chance to fail.
* MMP compatibility, the concept of concrete versus non-concrete devices
has slightly changed the semantics of vdev_writeable(). Update
mmp_random_leaf_impl() accordingly.
* Updated dbuf_remap() to handle the org.zfsonlinux:large_dnode pool
feature which is not supported by OpenZFS.
* Added support for new vdev removal tracepoints.
* Test cases removal_with_zdb and removal_condense_export have been
intentionally disabled. When run manually they pass as intended,
but when running in the automated test environment they produce
unreliable results on the latest Fedora release.
They may work better once the upstream pool import refectoring is
merged into ZoL at which point they will be re-enabled.
Authored by: Matthew Ahrens <mahrens@delphix.com>
Reviewed-by: Alex Reece <alex@delphix.com>
Reviewed-by: George Wilson <george.wilson@delphix.com>
Reviewed-by: John Kennedy <john.kennedy@delphix.com>
Reviewed-by: Prakash Surya <prakash.surya@delphix.com>
Reviewed by: Richard Laager <rlaager@wiktel.com>
Reviewed by: Tim Chase <tim@chase2k.com>
Reviewed by: Brian Behlendorf <behlendorf1@llnl.gov>
Approved by: Garrett D'Amore <garrett@damore.org>
Ported-by: Tim Chase <tim@chase2k.com>
Signed-off-by: Tim Chase <tim@chase2k.com>
OpenZFS-issue: https://www.illumos.org/issues/7614
OpenZFS-commit: https://github.com/openzfs/openzfs/commit/f539f1ebCloses#6900
Currently, the decryption and block authentication code in
the ZIO / ARC layers is a bit inconsistent with regards to
the ereports that are produces and the error codes that are
passed to calling functions. This patch ensures that all of
these errors (which begin as ECKSUM) are converted to EIO
before they leave the ZIO or ARC layer and that ereports
are correctly generated on each decryption / authentication
failure.
In addition, this patch fixes a bug in zio_decrypt() where
ECKSUM never gets written to zio->io_error.
Reviewed by: Matt Ahrens <matt@delphix.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Tom Caputi <tcaputi@datto.com>
Closes#7372
When the pool is suspended, record whether it was due to an I/O error or
due to MMP writes failing to succeed within the required time.
Change spa_suspended from uint8_t to zio_suspend_reason_t to store the
reason.
When userspace queries pool status via spa_tryimport(), report the
reason the pool was suspended in a new key,
ZPOOL_CONFIG_SUSPENDED_REASON.
In libzfs, when interpreting the returned config nvlist, report
suspension due to MMP with a new pool status enum value,
ZPOOL_STATUS_IO_FAILURE_MMP.
In status_callback(), which generates and emits the message when 'zpool
status' is executed, add a case to print an appropriate message for the
new pool status enum value.
Reviewed-by: George Melikov <mail@gmelikov.ru>
Reviewed-by: Giuseppe Di Natale <dinatale2@llnl.gov>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Tony Hutter <hutter2@llnl.gov>
Signed-off-by: Olaf Faaland <faaland1@llnl.gov>
Closes#7296
Currently, the DMU relies on ZIO layer compression to free LO
dnode blocks that no longer have objects in them. However,
raw receives disable all compression, meaning that these blocks
can never be freed. In addition to the obvious space concerns,
this could also cause incremental raw receives to fail to mount
since the MAC of a hole is different from that of a completely
zeroed block.
This patch corrects this issue by adding a special case in
zio_write_compress() which will attempt to compress these blocks
to a hole even if ZIO_FLAG_RAW_ENCRYPT is set. This patch also
removes the zfs_mdcomp_disable tunable, since tuning it could
cause these same issues.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Tom Caputi <tcaputi@datto.com>
Closes#7198
PROBLEM
=======
It's possible for a parent zio to complete even though it has children
which have not completed. This can result in the following panic:
> $C
ffffff01809128c0 vpanic()
ffffff01809128e0 mutex_panic+0x58(fffffffffb94c904, ffffff597dde7f80)
ffffff0180912950 mutex_vector_enter+0x347(ffffff597dde7f80)
ffffff01809129b0 zio_remove_child+0x50(ffffff597dde7c58, ffffff32bd901ac0,
ffffff3373370908)
ffffff0180912a40 zio_done+0x390(ffffff32bd901ac0)
ffffff0180912a70 zio_execute+0x78(ffffff32bd901ac0)
ffffff0180912b30 taskq_thread+0x2d0(ffffff33bae44140)
ffffff0180912b40 thread_start+8()
> ::status
debugging crash dump vmcore.2 (64-bit) from batfs0390
operating system: 5.11 joyent_20170911T171900Z (i86pc)
image uuid: (not set)
panic message: mutex_enter: bad mutex, lp=ffffff597dde7f80
owner=ffffff3c59b39480 thread=ffffff0180912c40
dump content: kernel pages only
The problem is that dbuf_prefetch along with l2arc can create a zio tree
which confuses the parent zio and allows it to complete with while children
still exist. Here's the scenario:
zio tree:
pio
|--- lio
The parent zio, pio, has entered the zio_done stage and begins to check its
children to see there are still some that have not completed. In zio_done(),
the children are checked in the following order:
zio_wait_for_children(zio, ZIO_CHILD_VDEV, ZIO_WAIT_DONE)
zio_wait_for_children(zio, ZIO_CHILD_GANG, ZIO_WAIT_DONE)
zio_wait_for_children(zio, ZIO_CHILD_DDT, ZIO_WAIT_DONE)
zio_wait_for_children(zio, ZIO_CHILD_LOGICAL, ZIO_WAIT_DONE)
If pio, finds any child which has not completed then it stops executing and
goes to sleep. Each call to zio_wait_for_children() will grab the io_lock
while checking the particular child.
In this scenario, the pio has completed the first call to
zio_wait_for_children() to check for any ZIO_CHILD_VDEV children. Since
the only zio in the zio tree right now is the logical zio, lio, then it
completes that call and prepares to check the next child type.
In the meantime, the lio completes and in its callback creates a child vdev
zio, cio. The zio tree looks like this:
zio tree:
pio
|--- lio
|--- cio
The lio then grabs the parent's io_lock and removes itself.
zio tree:
pio
|--- cio
The pio continues to run but has already completed its check for ZIO_CHILD_VDEV
and will erroneously complete. When the child zio, cio, completes it will panic
the system trying to reference the parent zio which has been destroyed.
SOLUTION
========
The fix is to rework the zio_wait_for_children() logic to accept a bitfield
for all the children types that it's interested in checking. The
io_lock will is held the entire time we check all the children types. Since
the function now accepts a bitfield, a simple ZIO_CHILD_BIT() macro is provided
to allow for the conversion between a ZIO_CHILD type and the bitfield used by
the zio_wiat_for_children logic.
Authored by: George Wilson <george.wilson@delphix.com>
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Reviewed by: Andriy Gapon <avg@FreeBSD.org>
Reviewed by: Youzhong Yang <youzhong@gmail.com>
Reviewed by: Brian Behlendorf <behlendorf1@llnl.gov>
Approved by: Dan McDonald <danmcd@omniti.com>
Ported-by: Giuseppe Di Natale <dinatale2@llnl.gov>
OpenZFS-issue: https://www.illumos.org/issues/8857
OpenZFS-commit: https://github.com/openzfs/openzfs/commit/862ff6d99c
Issue #5918Closes#7168
The on-disk format for encrypted datasets protects not only
the encrypted and authenticated blocks themselves, but also
the order and interpretation of these blocks. In order to
make this work while maintaining the ability to do raw
sends, the indirect bps maintain a secure checksum of all
the MACs in the block below it along with a few other
fields that determine how the data is interpreted.
Unfortunately, the current on-disk format erroneously
includes some fields which are not portable and thus cannot
support raw sends. It is not possible to easily work around
this issue due to a separate and much smaller bug which
causes indirect blocks for encrypted dnodes to not be
compressed, which conflicts with the previous bug. In
addition, the current code generates incompatible on-disk
formats on big endian and little endian systems due to an
issue with how block pointers are authenticated. Finally,
raw send streams do not currently include dn_maxblkid when
sending both the metadnode and normal dnodes which are
needed in order to ensure that we are correctly maintaining
the portable objset MAC.
This patch zero's out the offending fields when computing
the bp MAC and ensures that these MACs are always
calculated in little endian order (regardless of the host
system's byte order). This patch also registers an errata
for the old on-disk format, which we detect by adding a
"version" field to newly created DSL Crypto Keys. We allow
datasets without a version (version 0) to only be mounted
for read so that they can easily be migrated. We also now
include dn_maxblkid in raw send streams to ensure the MAC
can be maintained correctly.
This patch also contains minor bug fixes and cleanups.
Reviewed-by: Jorgen Lundman <lundman@lundman.net>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Signed-off-by: Tom Caputi <tcaputi@datto.com>
Closes#6845Closes#6864Closes#7052
The intent of this patch is extend the existing deadman code
such that it's flexible enough to be used by both ztest and
on production systems. The proposed changes include:
* Added a new `zfs_deadman_failmode` module option which is
used to dynamically control the behavior of the deadman. It's
loosely modeled after, but independant from, the pool failmode
property. It can be set to wait, continue, or panic.
* wait - Wait for the "hung" I/O (default)
* continue - Attempt to recover from a "hung" I/O
* panic - Panic the system
* Added a new `zfs_deadman_ziotime_ms` module option which is
analogous to `zfs_deadman_synctime_ms` except instead of
applying to a pool TXG sync it applies to zio_wait(). A
default value of 300s is used to define a "hung" zio.
* The ztest deadman thread has been re-enabled by default,
aligned with the upstream OpenZFS code, and then extended
to terminate the process when it takes significantly longer
to complete than expected.
* The -G option was added to ztest to print the internal debug
log when a fatal error is encountered. This same option was
previously added to zdb in commit fa603f82. Update zloop.sh
to unconditionally pass -G to obtain additional debugging.
* The FM_EREPORT_ZFS_DELAY event which was previously posted
when the deadman detect a "hung" pool has been replaced by
a new dedicated FM_EREPORT_ZFS_DEADMAN event.
* The proposed recovery logic attempts to restart a "hung"
zio by calling zio_interrupt() on any outstanding leaf zios.
We may want to further restrict this to zios in either the
ZIO_STAGE_VDEV_IO_START or ZIO_STAGE_VDEV_IO_DONE stages.
Calling zio_interrupt() is expected to only be useful for
cases when an IO has been submitted to the physical device
but for some reasonable the completion callback hasn't been
called by the lower layers. This shouldn't be possible but
has been observed and may be caused by kernel/driver bugs.
* The 'zfs_deadman_synctime_ms' default value was reduced from
1000s to 600s.
* Depending on how ztest fails there may be no cache file to
move. This should not be considered fatal, collect the logs
which are available and carry on.
* Add deadman test cases for spa_deadman() and zio_wait().
* Increase default zfs_deadman_checktime_ms to 60s.
Reviewed-by: Tim Chase <tim@chase2k.com>
Reviewed by: Thomas Caputi <tcaputi@datto.com>
Reviewed-by: Giuseppe Di Natale <dinatale2@llnl.gov>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#6999
Authored by: Prakash Surya <prakash.surya@delphix.com>
Reviewed by: John Kennedy <jwk404@gmail.com>
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Reviewed by: George Wilson <george.wilson@delphix.com>
Reviewed by: Brad Lewis <brad.lewis@delphix.com>
Reviewed by: Igor Kozhukhov <igor@dilos.org>
Reviewed by: Brian Behlendorf <behlendorf1@llnl.gov>
Approved by: Robert Mustacchi <rm@joyent.com>
Ported-by: Prakash Surya <prakash.surya@delphix.com>
PROBLEM
=======
There's a race condition that exists if `zil_free_lwb` races with either
`zil_commit_waiter_timeout` and/or `zil_lwb_flush_vdevs_done`.
Here's an example panic due to this bug:
> ::status
debugging crash dump vmcore.0 (64-bit) from ip-10-110-205-40
operating system: 5.11 dlpx-5.2.2.0_2017-12-04-17-28-32b6ba51fb (i86pc)
image uuid: 4af0edfb-e58e-6ed8-cafc-d3e9167c7513
panic message:
BAD TRAP: type=e (#pf Page fault) rp=ffffff0010555970 addr=60 occurred in module "zfs" due to a NULL pointer dereference
dump content: kernel pages only
> $c
zio_shrink+0x12()
zil_lwb_write_issue+0x30d(ffffff03dcd15cc0, ffffff03e0730e20)
zil_commit_waiter_timeout+0xa2(ffffff03dcd15cc0, ffffff03d97ffcf8)
zil_commit_waiter+0xf3(ffffff03dcd15cc0, ffffff03d97ffcf8)
zil_commit+0x80(ffffff03dcd15cc0, 9a9)
zfs_write+0xc34(ffffff03dc38b140, ffffff0010555e60, 40, ffffff03e00fb758, 0)
fop_write+0x5b(ffffff03dc38b140, ffffff0010555e60, 40, ffffff03e00fb758, 0)
write+0x250(42, fffffd7ff4832000, 2000)
sys_syscall+0x177()
If there's an outstanding lwb that's in `zil_commit_waiter_timeout`
waiting to timeout, waiting on it's waiter's CV, we must be sure not to
call `zil_free_lwb`. If we end up calling `zil_free_lwb`, then that LWB
may be freed and can result in a use-after-free situation where the
stale lwb pointer stored in the `zil_commit_waiter_t` structure of the
thread waiting on the waiter's CV is used.
A similar situation can occur if an lwb is issued to disk, and thus in
the `LWB_STATE_ISSUED` state, and `zil_free_lwb` is called while the
disk is servicing that lwb. In this situation, the lwb will be freed by
`zil_free_lwb`, which will result in a use-after-free situation when the
lwb's zio completes, and `zil_lwb_flush_vdevs_done` is called.
This race condition is prevented in `zil_close` by calling `zil_commit`
before `zil_free_lwb` is called, which will ensure all outstanding (i.e.
all lwb's in the `LWB_STATE_OPEN` and/or `LWB_STATE_ISSUED` states)
reach the `LWB_STATE_DONE` state before the lwb's are freed
(`zil_commit` will not return untill all the lwb's are
`LWB_STATE_DONE`).
Further, this race condition is prevented in `zil_sync` by only calling
`zil_free_lwb` for lwb's that do not have their `lwb_buf` pointer set.
All lwb's not in the `LWB_STATE_DONE` state will have a non-null value
for this pointer; the pointer is only cleared in
`zil_lwb_flush_vdevs_done`, at which point the lwb's state will be
changed to `LWB_STATE_DONE`.
This race *is* present in `zil_suspend`, leading to this bug.
At first glance, it would appear as though this would not be true
because `zil_suspend` will call `zil_commit`, just like `zil_close`, but
the problem is that `zil_suspend` will set the zilog's `zl_suspend`
field prior to calling `zil_commit`. Further, in `zil_commit`, if
`zl_suspend` is set, `zil_commit` will take a special branch of logic
and use `txg_wait_synced` instead of performing the normal `zil_commit`
logic.
This call to `txg_wait_synced` might be good enough for the data to
reach disk safely before it returns, but it does not ensure that all
outstanding lwb's reach the `LWB_STATE_DONE` state before it returns.
This is because, if there's an lwb "stuck" in
`zil_commit_waiter_timeout`, waiting for it's lwb to timeout, it will
maintain a non-null value for it's `lwb_buf` field and thus `zil_sync`
will not free that lwb. Thus, even though the lwb's data is already on
disk, the lwb will be left lingering, waiting on the CV, and will
eventually timeout and be issued to disk even though the write is
unnecessary.
So, after `zil_commit` is called from `zil_suspend`, we incorrectly
assume that there are not outstanding lwb's, and proceed to free all
lwb's found on the zilog's lwb list. As a result, we free the lwb that
will later be used `zil_commit_waiter_timeout`.
SOLUTION
========
The solution to this, is to ensure all outstanding lwb's complete before
calling `zil_free_lwb` via `zil_destroy` in `zil_suspend`. This patch
accomplishes this goal by forcing the normal `zil_commit` logic when
called from `zil_sync`.
Now, `zil_suspend` will call `zil_commit_impl` which will always use the
normal logic of waiting/issuing lwb's to disk before it returns. As a
result, any lwb's outstanding when `zil_commit_impl` is called will be
guaranteed to reach the `LWB_STATE_DONE` state by the time it returns.
Further, no new lwb's will be created via `zil_commit` since the zilog's
`zl_suspend` flag will be set. This will force all new callers of
`zil_commit` to use `txg_wait_synced` instead of creating and issuing
new lwb's.
Thus, all lwb's left on the zilog's lwb list when `zil_destroy` is
called will be in the `LWB_STATE_DONE` state, and we'll avoid this race
condition.
OpenZFS-issue: https://www.illumos.org/issues/8909
OpenZFS-commit: https://github.com/openzfs/openzfs/commit/ece62b6f8dCloses#6940
When sequential scrubs were merged, all calls to arc_read()
(including prefetch IOs) were given ZIO_PRIORITY_ASYNC_READ.
Unfortunately, this behaves badly with an existing issue where
prefetch IOs cannot be re-prioritized after the issue. The
result is that synchronous reads end up in the same vdev_queue
as the scrub IOs and can have (in some workloads) multiple
seconds of latency.
This patch incorporates 2 changes. The first ensures that all
scrub IOs are given ZIO_PRIORITY_SCRUB to allow the vdev_queue
code to differentiate between these I/Os and user prefetches.
Second, this patch introduces zio_change_priority() to provide
the missing capability to upgrade a zio's priority.
Reviewed by: George Wilson <george.wilson@delphix.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Tom Caputi <tcaputi@datto.com>
Closes#6921Closes#6926
Authored by: Prakash Surya <prakash.surya@delphix.com>
Reviewed by: Brad Lewis <brad.lewis@delphix.com>
Reviewed by: Matt Ahrens <mahrens@delphix.com>
Reviewed by: George Wilson <george.wilson@delphix.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Approved by: Dan McDonald <danmcd@joyent.com>
Ported-by: Prakash Surya <prakash.surya@delphix.com>
Problem
=======
The current implementation of zil_commit() can introduce significant
latency, beyond what is inherent due to the latency of the underlying
storage. The additional latency comes from two main problems:
1. When there's outstanding ZIL blocks being written (i.e. there's
already a "writer thread" in progress), then any new calls to
zil_commit() will block waiting for the currently oustanding ZIL
blocks to complete. The blocks written for each "writer thread" is
coined a "batch", and there can only ever be a single "batch" being
written at a time. When a batch is being written, any new ZIL
transactions will have to wait for the next batch to be written,
which won't occur until the current batch finishes.
As a result, the underlying storage may not be used as efficiently
as possible. While "new" threads enter zil_commit() and are blocked
waiting for the next batch, it's possible that the underlying
storage isn't fully utilized by the current batch of ZIL blocks. In
that case, it'd be better to allow these new threads to generate
(and issue) a new ZIL block, such that it could be serviced by the
underlying storage concurrently with the other ZIL blocks that are
being serviced.
2. Any call to zil_commit() must wait for all ZIL blocks in its "batch"
to complete, prior to zil_commit() returning. The size of any given
batch is proportional to the number of ZIL transaction in the queue
at the time that the batch starts processing the queue; which
doesn't occur until the previous batch completes. Thus, if there's a
lot of transactions in the queue, the batch could be composed of
many ZIL blocks, and each call to zil_commit() will have to wait for
all of these writes to complete (even if the thread calling
zil_commit() only cared about one of the transactions in the batch).
To further complicate the situation, these two issues result in the
following side effect:
3. If a given batch takes longer to complete than normal, this results
in larger batch sizes, which then take longer to complete and
further drive up the latency of zil_commit(). This can occur for a
number of reasons, including (but not limited to): transient changes
in the workload, and storage latency irregularites.
Solution
========
The solution attempted by this change has the following goals:
1. no on-disk changes; maintain current on-disk format.
2. modify the "batch size" to be equal to the "ZIL block size".
3. allow new batches to be generated and issued to disk, while there's
already batches being serviced by the disk.
4. allow zil_commit() to wait for as few ZIL blocks as possible.
5. use as few ZIL blocks as possible, for the same amount of ZIL
transactions, without introducing significant latency to any
individual ZIL transaction. i.e. use fewer, but larger, ZIL blocks.
In theory, with these goals met, the new allgorithm will allow the
following improvements:
1. new ZIL blocks can be generated and issued, while there's already
oustanding ZIL blocks being serviced by the storage.
2. the latency of zil_commit() should be proportional to the underlying
storage latency, rather than the incoming synchronous workload.
Porting Notes
=============
Due to the changes made in commit 119a394ab0, the lifetime of an itx
structure differs than in OpenZFS. Specifically, the itx structure is
kept around until the data associated with the itx is considered to be
safe on disk; this is so that the itx's callback can be called after the
data is committed to stable storage. Since OpenZFS doesn't have this itx
callback mechanism, it's able to destroy the itx structure immediately
after the itx is committed to an lwb (before the lwb is written to
disk).
To support this difference, and to ensure the itx's callbacks can still
be called after the itx's data is on disk, a few changes had to be made:
* A list of itxs was added to the lwb structure. This list contains
all of the itxs that have been committed to the lwb, such that the
callbacks for these itxs can be called from zil_lwb_flush_vdevs_done(),
after the data for the itxs is committed to disk.
* A list of itxs was added on the stack of the zil_process_commit_list()
function; the "nolwb_itxs" list. In some circumstances, an itx may
not be committed to an lwb (e.g. if allocating the "next" ZIL block
on disk fails), so this list is used to keep track of which itxs
fall into this state, such that their callbacks can be called after
the ZIL's writer pipeline is "stalled".
* The logic to actually call the itx's callback was moved into the
zil_itx_destroy() function. Since all consumers of zil_itx_destroy()
were effectively performing the same logic (i.e. if callback is
non-null, call the callback), it seemed like useful code cleanup to
consolidate this logic into a single function.
Additionally, the existing Linux tracepoint infrastructure dealing with
the ZIL's probes and structures had to be updated to reflect these code
changes. Specifically:
* The "zil__cw1" and "zil__cw2" probes were removed, so they had to be
removed from "trace_zil.h" as well.
* Some of the zilog structure's fields were removed, which affected
the tracepoint definitions of the structure.
* New tracepoints had to be added for the following 3 new probes:
* zil__process__commit__itx
* zil__process__normal__itx
* zil__commit__io__error
OpenZFS-issue: https://www.illumos.org/issues/8585
OpenZFS-commit: https://github.com/openzfs/openzfs/commit/5d95a3aCloses#6566
Currently, scrubs and resilvers can take an extremely
long time to complete. This is largely due to the fact
that zfs scans process pools in logical order, as
determined by each block's bookmark. This makes sense
from a simplicity perspective, but blocks in zfs are
often scattered randomly across disks, particularly
due to zfs's copy-on-write mechanisms.
This patch improves performance by splitting scrubs
and resilvers into a metadata scanning phase and an IO
issuing phase. The metadata scan reads through the
structure of the pool and gathers an in-memory queue
of I/Os, sorted by size and offset on disk. The issuing
phase will then issue the scrub I/Os as sequentially as
possible, greatly improving performance.
This patch also updates and cleans up some of the scan
code which has not been updated in several years.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Authored-by: Saso Kiselkov <saso.kiselkov@nexenta.com>
Authored-by: Alek Pinchuk <apinchuk@datto.com>
Authored-by: Tom Caputi <tcaputi@datto.com>
Signed-off-by: Tom Caputi <tcaputi@datto.com>
Closes#3625Closes#6256
With PR 5756 the zfs module now supports c99 and the
remaining past c89 workarounds can be undone.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: George Melikov <mail@gmelikov.ru>
Signed-off-by: Don Brady <don.brady@delphix.com>
Closes#6816
* PBKDF2 implementation changed to OpenSSL implementation.
* HKDF implementation moved to its own file and tests
added to ensure correctness.
* Removed libzfs's now unnecessary dependency on libzpool
and libicp.
* Ztest can now create and test encrypted datasets. This is
currently disabled until issue #6526 is resolved, but
otherwise functions as advertised.
* Several small bug fixes discovered after enabling ztest
to run on encrypted datasets.
* Fixed coverity defects added by the encryption patch.
* Updated man pages for encrypted send / receive behavior.
* Fixed a bug where encrypted datasets could receive
DRR_WRITE_EMBEDDED records.
* Minor code cleanups / consolidation.
Signed-off-by: Tom Caputi <tcaputi@datto.com>
Added a 'corrupt' error option that will flip a bit in the data
after a read operation. This is useful for generating checksum
errors at the device layer (in a mirror config for example). It
is also used to validate the diagnosis of checksum errors from
the zfs diagnosis engine.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Don Brady <don.brady@intel.com>
Closes#6345
This change incorporates three major pieces:
The first change is a keystore that manages wrapping
and encryption keys for encrypted datasets. These
commands mostly involve manipulating the new
DSL Crypto Key ZAP Objects that live in the MOS. Each
encrypted dataset has its own DSL Crypto Key that is
protected with a user's key. This level of indirection
allows users to change their keys without re-encrypting
their entire datasets. The change implements the new
subcommands "zfs load-key", "zfs unload-key" and
"zfs change-key" which allow the user to manage their
encryption keys and settings. In addition, several new
flags and properties have been added to allow dataset
creation and to make mounting and unmounting more
convenient.
The second piece of this patch provides the ability to
encrypt, decyrpt, and authenticate protected datasets.
Each object set maintains a Merkel tree of Message
Authentication Codes that protect the lower layers,
similarly to how checksums are maintained. This part
impacts the zio layer, which handles the actual
encryption and generation of MACs, as well as the ARC
and DMU, which need to be able to handle encrypted
buffers and protected data.
The last addition is the ability to do raw, encrypted
sends and receives. The idea here is to send raw
encrypted and compressed data and receive it exactly
as is on a backup system. This means that the dataset
on the receiving system is protected using the same
user key that is in use on the sending side. By doing
so, datasets can be efficiently backed up to an
untrusted system without fear of data being
compromised.
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Jorgen Lundman <lundman@lundman.net>
Signed-off-by: Tom Caputi <tcaputi@datto.com>
Closes#494Closes#5769
If fault injection is enabled, the ZIO_FLAG_IO_RETRY could be set by
zio_handle_device_injection() to generate the FMA events and update
stats. Hence, ignore the flag and process such zios.
A better fix would be to add another flag in the zio_t to indicate that
the zio is failed because of a zinject rule. However, considering the
fact that we do this in debug bits, we could do with the crude check
using the global flag zio_injection_enabled which is set to 1 when
zinject records are added.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Sanjeev Bagewadi <sanjeev.bagewadi@gmail.com>
Closes#6383Closes#6384
While investigating https://github.com/zfsonlinux/zfs/issues/6425 I
noticed that ioctl ZIOs were not setting zio->io_delay correctly. They
would set the start time in zio_vdev_io_start(), but never set the end
time in zio_vdev_io_done(), since ioctls skip it and go straight to
zio_done(). This was causing spurious "delayed IO" events to appear,
which would eventually get rate-limited and displayed as
"Missed events" messages in zed.
To get around the problem, this patch only sets zio->io_delay for read
and write ZIOs, since that's all we care about anyway.
Reviewed-by: Giuseppe Di Natale <dinatale2@llnl.gov>
Reviewed-by: George Melikov <mail@gmelikov.ru>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Tony Hutter <hutter2@llnl.gov>
Closes#6425Closes#6440
This reverts commit cc9c6bc, which has been causing intermittent
test failures on buildbot. A correct fix for this locking issue
has been applied in a separate patch.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Olaf Faaland <faaland1@llnl.gov>
When an IO fails then zio_vdev_io_done() can call vdev_probe()
to determine the health of the vdev. This is safe as long as
the original zio was submitted with zio_wait() and holds the
SCL_STATE_ALL lock over the operation.
If zio_no_wait() was used then the done callback will submit
the probe IO outside the SCL_STATE_ALL lock and hit this
ASSERT in zio_create()
ASSERT(!vd || spa_config_held(spa, SCL_STATE_ALL, RW_READER));
Resolve the issue by only allowing vdev_probe() to be called
when there's a waiter indicating the caller is using zio_wait().
This assumes that caller is still holding SCL_STATE_ALL.
This issue isn't MMP specific but was surfaced when testing.
Without this patch it can be reproduced by running:
zpool set multihost on <pool>
zinject -d <vdev> -e io -T write -f 50 <pool> -L uber
Reviewed-by: Olaf Faaland <faaland1@llnl.gov>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Don Brady <don.brady@intel.com>
Closes#745Closes#6279
- After some ZIL changes 6 years ago zil_slog_limit got partially broken
due to zl_itx_list_sz not updated when async itx'es upgraded to sync.
Actually because of other changes about that time zl_itx_list_sz is not
really required to implement the functionality, so this patch removes
some unneeded broken code and variables.
- Original idea of zil_slog_limit was to reduce chance of SLOG abuse by
single heavy logger, that increased latency for other (more latency critical)
loggers, by pushing heavy log out into the main pool instead of SLOG. Beside
huge latency increase for heavy writers, this implementation caused double
write of all data, since the log records were explicitly prepared for SLOG.
Since we now have I/O scheduler, I've found it can be much more efficient
to reduce priority of heavy logger SLOG writes from ZIO_PRIORITY_SYNC_WRITE
to ZIO_PRIORITY_ASYNC_WRITE, while still leave them on SLOG.
- Existing ZIL implementation had problem with space efficiency when it
has to write large chunks of data into log blocks of limited size. In some
cases efficiency stopped to almost as low as 50%. In case of ZIL stored on
spinning rust, that also reduced log write speed in half, since head had to
uselessly fly over allocated but not written areas. This change improves
the situation by offloading problematic operations from z*_log_write() to
zil_lwb_commit(), which knows real situation of log blocks allocation and
can split large requests into pieces much more efficiently. Also as side
effect it removes one of two data copy operations done by ZIL code WR_COPIED
case.
- While there, untangle and unify code of z*_log_write() functions.
Also zfs_log_write() alike to zvol_log_write() can now handle writes crossing
block boundary, that may also improve efficiency if ZPL is made to do that.
Sponsored by: iXsystems, Inc.
Authored by: Alexander Motin <mav@FreeBSD.org>
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Reviewed by: Prakash Surya <prakash.surya@delphix.com>
Reviewed by: Andriy Gapon <avg@FreeBSD.org>
Reviewed by: Steven Hartland <steven.hartland@multiplay.co.uk>
Reviewed by: Brad Lewis <brad.lewis@delphix.com>
Reviewed by: Richard Elling <Richard.Elling@RichardElling.com>
Approved by: Robert Mustacchi <rm@joyent.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Richard Yao <ryao@gentoo.org>
Ported-by: Giuseppe Di Natale <dinatale2@llnl.gov>
OpenZFS-issue: https://www.illumos.org/issues/7578
OpenZFS-commit: https://github.com/openzfs/openzfs/commit/aeb13acCloses#6191
