4045 zfs write throttle & i/o scheduler performance work
1. The ZFS i/o scheduler (vdev_queue.c) now divides i/os into 5 classes: sync
read, sync write, async read, async write, and scrub/resilver. The scheduler
issues a number of concurrent i/os from each class to the device. Once a class
has been selected, an i/o is selected from this class using either an elevator
algorithem (async, scrub classes) or FIFO (sync classes). The number of
concurrent async write i/os is tuned dynamically based on i/o load, to achieve
good sync i/o latency when there is not a high load of writes, and good write
throughput when there is. See the block comment in vdev_queue.c (reproduced
below) for more details.
2. The write throttle (dsl_pool_tempreserve_space() and
txg_constrain_throughput()) is rewritten to produce much more consistent delays
when under constant load. The new write throttle is based on the amount of
dirty data, rather than guesses about future performance of the system. When
there is a lot of dirty data, each transaction (e.g. write() syscall) will be
delayed by the same small amount. This eliminates the "brick wall of wait"
that the old write throttle could hit, causing all transactions to wait several
seconds until the next txg opens. One of the keys to the new write throttle is
decrementing the amount of dirty data as i/o completes, rather than at the end
of spa_sync(). Note that the write throttle is only applied once the i/o
scheduler is issuing the maximum number of outstanding async writes. See the
block comments in dsl_pool.c and above dmu_tx_delay() (reproduced below) for
more details.
This diff has several other effects, including:
* the commonly-tuned global variable zfs_vdev_max_pending has been removed;
use per-class zfs_vdev_*_max_active values or zfs_vdev_max_active instead.
* the size of each txg (meaning the amount of dirty data written, and thus the
time it takes to write out) is now controlled differently. There is no longer
an explicit time goal; the primary determinant is amount of dirty data.
Systems that are under light or medium load will now often see that a txg is
always syncing, but the impact to performance (e.g. read latency) is minimal.
Tune zfs_dirty_data_max and zfs_dirty_data_sync to control this.
* zio_taskq_batch_pct = 75 -- Only use 75% of all CPUs for compression,
checksum, etc. This improves latency by not allowing these CPU-intensive tasks
to consume all CPU (on machines with at least 4 CPU's; the percentage is
rounded up).
--matt
APPENDIX: problems with the current i/o scheduler
The current ZFS i/o scheduler (vdev_queue.c) is deadline based. The problem
with this is that if there are always i/os pending, then certain classes of
i/os can see very long delays.
For example, if there are always synchronous reads outstanding, then no async
writes will be serviced until they become "past due". One symptom of this
situation is that each pass of the txg sync takes at least several seconds
(typically 3 seconds).
If many i/os become "past due" (their deadline is in the past), then we must
service all of these overdue i/os before any new i/os. This happens when we
enqueue a batch of async writes for the txg sync, with deadlines 2.5 seconds in
the future. If we can't complete all the i/os in 2.5 seconds (e.g. because
there were always reads pending), then these i/os will become past due. Now we
must service all the "async" writes (which could be hundreds of megabytes)
before we service any reads, introducing considerable latency to synchronous
i/os (reads or ZIL writes).
Notes on porting to ZFS on Linux:
- zio_t gained new members io_physdone and io_phys_children. Because
object caches in the Linux port call the constructor only once at
allocation time, objects may contain residual data when retrieved
from the cache. Therefore zio_create() was updated to zero out the two
new fields.
- vdev_mirror_pending() relied on the depth of the per-vdev pending queue
(vq->vq_pending_tree) to select the least-busy leaf vdev to read from.
This tree has been replaced by vq->vq_active_tree which is now used
for the same purpose.
- vdev_queue_init() used the value of zfs_vdev_max_pending to determine
the number of vdev I/O buffers to pre-allocate. That global no longer
exists, so we instead use the sum of the *_max_active values for each of
the five I/O classes described above.
- The Illumos implementation of dmu_tx_delay() delays a transaction by
sleeping in condition variable embedded in the thread
(curthread->t_delay_cv). We do not have an equivalent CV to use in
Linux, so this change replaced the delay logic with a wrapper called
zfs_sleep_until(). This wrapper could be adopted upstream and in other
downstream ports to abstract away operating system-specific delay logic.
- These tunables are added as module parameters, and descriptions added
to the zfs-module-parameters.5 man page.
spa_asize_inflation
zfs_deadman_synctime_ms
zfs_vdev_max_active
zfs_vdev_async_write_active_min_dirty_percent
zfs_vdev_async_write_active_max_dirty_percent
zfs_vdev_async_read_max_active
zfs_vdev_async_read_min_active
zfs_vdev_async_write_max_active
zfs_vdev_async_write_min_active
zfs_vdev_scrub_max_active
zfs_vdev_scrub_min_active
zfs_vdev_sync_read_max_active
zfs_vdev_sync_read_min_active
zfs_vdev_sync_write_max_active
zfs_vdev_sync_write_min_active
zfs_dirty_data_max_percent
zfs_delay_min_dirty_percent
zfs_dirty_data_max_max_percent
zfs_dirty_data_max
zfs_dirty_data_max_max
zfs_dirty_data_sync
zfs_delay_scale
The latter four have type unsigned long, whereas they are uint64_t in
Illumos. This accommodates Linux's module_param() supported types, but
means they may overflow on 32-bit architectures.
The values zfs_dirty_data_max and zfs_dirty_data_max_max are the most
likely to overflow on 32-bit systems, since they express physical RAM
sizes in bytes. In fact, Illumos initializes zfs_dirty_data_max_max to
2^32 which does overflow. To resolve that, this port instead initializes
it in arc_init() to 25% of physical RAM, and adds the tunable
zfs_dirty_data_max_max_percent to override that percentage. While this
solution doesn't completely avoid the overflow issue, it should be a
reasonable default for most systems, and the minority of affected
systems can work around the issue by overriding the defaults.
- Fixed reversed logic in comment above zfs_delay_scale declaration.
- Clarified comments in vdev_queue.c regarding when per-queue minimums take
effect.
- Replaced dmu_tx_write_limit in the dmu_tx kstat file
with dmu_tx_dirty_delay and dmu_tx_dirty_over_max. The first counts
how many times a transaction has been delayed because the pool dirty
data has exceeded zfs_delay_min_dirty_percent. The latter counts how
many times the pool dirty data has exceeded zfs_dirty_data_max (which
we expect to never happen).
- The original patch would have regressed the bug fixed in
zfsonlinux/zfs@c418410, which prevented users from setting the
zfs_vdev_aggregation_limit tuning larger than SPA_MAXBLOCKSIZE.
A similar fix is added to vdev_queue_aggregate().
- In vdev_queue_io_to_issue(), dynamically allocate 'zio_t search' on the
heap instead of the stack. In Linux we can't afford such large
structures on the stack.
Reviewed by: George Wilson <george.wilson@delphix.com>
Reviewed by: Adam Leventhal <ahl@delphix.com>
Reviewed by: Christopher Siden <christopher.siden@delphix.com>
Reviewed by: Ned Bass <bass6@llnl.gov>
Reviewed by: Brendan Gregg <brendan.gregg@joyent.com>
Approved by: Robert Mustacchi <rm@joyent.com>
References:
http://www.illumos.org/issues/4045illumos/illumos-gate@69962b5647
Ported-by: Ned Bass <bass6@llnl.gov>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#1913
Currently, using msync() results in the following code path:
sys_msync -> zpl_fsync -> filemap_write_and_wait_range -> zpl_writepages -> write_cache_pages -> zpl_putpage
In such a code path, zil_commit() is called as part of zpl_putpage().
This means that for each page, the write is handed to the DMU, the ZIL
is committed, and only then do we move on to the next page. As one might
imagine, this results in atrocious performance where there is a large
number of pages to write: instead of committing a batch of N writes,
we do N commits containing one page each. In some extreme cases this
can result in msync() being ~700 times slower than it should be, as well
as very inefficient use of ZIL resources.
This patch fixes this issue by making sure that the requested writes
are batched and then committed only once. Unfortunately, the
implementation is somewhat non-trivial because there is no way to run
write_cache_pages in SYNC mode (so that we get all pages) without
making it wait on the writeback tag for each page.
The solution implemented here is composed of two parts:
- I added a new callback system to the ZIL, which allows the caller to
be notified when its ITX gets written to stable storage. One nice
thing is that the callback is called not only in zil_commit() but
in zil_sync() as well, which means that the caller doesn't have to
care whether the write ended up in the ZIL or the DMU: it will get
notified as soon as it's safe, period. This is an improvement over
dmu_tx_callback_register() that was used previously, which only
supports DMU writes. The rationale for this change is to allow
zpl_putpage() to be notified when a ZIL commit is completed without
having to block on zil_commit() itself.
- zpl_writepages() now calls write_cache_pages in non-SYNC mode, which
will prevent (1) write_cache_pages from blocking, and (2) zpl_putpage
from issuing ZIL commits. zpl_writepages() will issue the commit
itself instead of relying on zpl_putpage() to do it, thus nicely
batching the writes. Note, however, that we still have to call
write_cache_pages() again in SYNC mode because there is an edge case
documented in the implementation of write_cache_pages() whereas it
will not give us all dirty pages when running in non-SYNC mode. Thus
we need to run it at least once in SYNC mode to make sure we honor
persistency guarantees. This only happens when the pages are
modified at the same time msync() is running, which should be rare.
In most cases there won't be any additional pages and this second
call will do nothing.
Note that this change also fixes a bug related to #907 whereas calling
msync() on pages that were already handed over to the DMU in a previous
writepages() call would make msync() block until the next TXG sync
instead of returning as soon as the ZIL commit is complete. The new
callback system fixes that problem.
Signed-off-by: Richard Yao <ryao@gentoo.org>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#1849Closes#907
Because ZFS bypasses the page cache we don't inherit per-task I/O
accounting for free. However, the Linux kernel does provide helper
functions allow us to perform our own accounting. These are most
commonly used for direct IO which also bypasses the page cache, but
they can be used for the common read/write call paths as well.
Signed-off-by: Pavel Snajdr <snajpa@snajpa.net>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#313Closes#1275
torvalds/linux@24f7c6 introduced a new shrinker API while
torvalds/linux@a0b021 dropped support for the old shrinker API.
This patch adds support for the new shrinker API by wrapping
the old one with the new one.
This change also reorganizes the autotools checks on the shrinker
API such that the configure script will fail early if an unknown
API is encountered in the future.
Support for the set_shrinker() API which was used by Linux 2.6.22
and older has been dropped. As a general rule compatibility is
only maintained back to Linux 2.6.26.
Signed-off-by: Richard Yao <ryao@gentoo.org>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closeszfsonlinux/zfs#1732Closeszfsonlinux/zfs#1822Closes#293Closes#307
The required Posix ACL interfaces are only available for kernels
with CONFIG_FS_POSIX_ACL defined. Therefore, only enable Posix
ACL support for these kernels. All major distribution kernels
enable CONFIG_FS_POSIX_ACL by default.
If your kernel does not support Posix ACLs the following warning
will be printed at ZFS module load time.
"ZFS: Posix ACLs disabled by kernel"
Signed-off-by: Massimo Maggi <me@massimo-maggi.eu>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#1825
3956 ::vdev -r should work with pipelines
3957 ztest should update the cachefile before killing itself
3958 multiple scans can lead to partial resilvering
3959 ddt entries are not always resilvered
3960 dsl_scan can skip over dedup-ed blocks if physical birth != logical birth
3961 freed gang blocks are not resilvered and can cause pool to suspend
3962 ztest should print out zfs debug buffer before exiting
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Reviewed by: Adam Leventhal <ahl@delphix.com>
Approved by: Richard Lowe <richlowe@richlowe.net>
References:
https://www.illumos.org/issues/3956https://www.illumos.org/issues/3957https://www.illumos.org/issues/3958https://www.illumos.org/issues/3959https://www.illumos.org/issues/3960https://www.illumos.org/issues/3961https://www.illumos.org/issues/3962illumos/illumos-gate@b4952e17e8
Ported-by: Richard Yao <ryao@gentoo.org>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Porting notes:
1. zfs_dbgmsg_print() is only used in userland. Since we do not have
mdb on Linux, it does not make sense to make it available in the
kernel. This means that a build failure will occur if any future
kernel patch depends on it. However, that is unlikely given that
this functionality was added to support zdb.
2. zfs_dbgmsg_print() is only invoked for -VVV or greater log levels.
This preserves the existing behavior of minimal noise when running
with -V, and -VV.
3. In vdev_config_generate() the call to nvlist_alloc() was not
changed to fnvlist_alloc() because we must pass KM_PUSHPAGE in
the txg_sync context.
3740 Poor ZFS send / receive performance due to snapshot
hold / release processing
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Approved by: Christopher Siden <christopher.siden@delphix.com>
References:
https://www.illumos.org/issues/3740illumos/illumos-gate@a7a845e4bf
Ported-by: Richard Yao <ryao@gentoo.org>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #1775
Porting notes:
1. 13fe019870 introduced a merge conflict
in dsl_dataset_user_release_tmp where some variables were moved
outside of the preprocessor directive.
2. dea9dfefdd747534b3846845629d2200f0616dad made the previous merge
conflict worse by switching KM_SLEEP to KM_PUSHPAGE. This is notable
because this commit refactors the code, adding a new KM_SLEEP
allocation. It is not clear to me whether this should be converted
to KM_PUSHPAGE.
3. We had a merge conflict in libzfs_sendrecv.c because of copyright
notices.
4. Several small C99 compatibility fixed were made.
3744 zfs shouldn't ignore errors unmounting snapshots
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Approved by: Christopher Siden <christopher.siden@delphix.com>
References:
https://www.illumos.org/issues/3744illumos/illumos-gate@fc7a6e3fef
Ported-by: Richard Yao <ryao@gentoo.org>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #1775
Porting notes:
1. There is no clear way to distinguish between a failure when we
tried to unmount the snapdir of a zvol (which does not exist)
and the failure when we try to unmount a snapdir of a dataset,
so the changes to zfs_unmount_snap() were dropped in favor of
an altered Linux function that unconditionally returns 0.
Needed for Illumos #3582. This interface is supposed to support
a variable-resolution timeout with nanosecond granularity. This
implementation rounds up to microsecond resolution, as nanosecond-
precision timing is rarely needed for real-world performance
tuning and may incur unnecessary busy-waiting. usleep_range() is
used if available, otherwise udelay() or msleep() are used
depending on the length of the delay interval.
Add flags from sys/callo.h as these are used to control the behavior of
cv_timedwait_hires(). Specifically,
CALLOUT_FLAG_ABSOLUTE
Normally, the expiration passed to the timeout API functions is
an expiration interval. If this flag is specified, then it is
interpreted as the expiration time itself.
CALLOUT_FLAG_ROUNDUP
Roundup the expiration time to the next resolution boundary. If this
flag is not specified, the expiration time is rounded down.
References:
https://www.illumos.org/issues/3582illumos/illumos-gate@0689f76
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#304
3642 dsl_scan_active() should not issue I/O to determine if async
destroying is active
3643 txg_delay should not hold the tc_lock
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Reviewed by: Adam Leventhal <ahl@delphix.com>
Approved by: Gordon Ross <gwr@nexenta.com>
References:
https://www.illumos.org/issues/3642https://www.illumos.org/issues/3643illumos/illumos-gate@4a92375985
Ported-by: Richard Yao <ryao@gentoo.org>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #1775
Porting Notes:
1. The alignment assumptions for the tx_cpu structure assume that
a kmutex_t is 8 bytes. This isn't true under Linux but tc_pad[]
was adjusted anyway for consistency since this structure was
never carefully aligned in ZoL. If careful alignment does impact
performance significantly this should be reworked to be portable.
3598 want to dtrace when errors are generated in zfs
Reviewed by: Dan Kimmel <dan.kimmel@delphix.com>
Reviewed by: Adam Leventhal <ahl@delphix.com>
Reviewed by: Christopher Siden <christopher.siden@delphix.com>
Approved by: Garrett D'Amore <garrett@damore.org>
References:
https://www.illumos.org/issues/3598illumos/illumos-gate@be6fd75a69
Ported-by: Richard Yao <ryao@gentoo.org>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #1775
Porting notes:
1. include/sys/zfs_context.h has been modified to render some new
macros inert until dtrace is available on Linux.
2. Linux-specific changes have been adapted to use SET_ERROR().
3. I'm NOT happy about this change. It does nothing but ugly
up the code under Linux. Unfortunately we need to take it to
avoid more merge conflicts in the future. -Brian
This change adds support for Posix ACLs by storing them as an xattr
which is common practice for many Linux file systems. Since the
Posix ACL is stored as an xattr it will not overwrite any existing
ZFS/NFSv4 ACLs which may have been set. The Posix ACL will also
be non-functional on other platforms although it may be visible
as an xattr if that platform understands SA based xattrs.
By default Posix ACLs are disabled but they may be enabled with
the new 'aclmode=noacl|posixacl' property. Set the property to
'posixacl' to enable them. If ZFS/NFSv4 ACL support is ever added
an appropriate acltype will be added.
This change passes the POSIX Test Suite cleanly with the exception
of xacl/00.t test 45 which is incorrect for Linux (Ext4 fails too).
http://www.tuxera.com/community/posix-test-suite/
Signed-off-by: Massimo Maggi <me@massimo-maggi.eu>
Signed-off-by: Richard Yao <ryao@gentoo.org>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#170
This change introduces zpool_get_prop_literal. It's an expanded version
of zpool_get_prop taking one additional boolean parameter. With this
parameter set to B_FALSE it will behave identically to zpool_get_prop.
Setting it to B_TRUE will return full precision numbers for the
following properties:
ZPOOL_PROP_SIZE
ZPOOL_PROP_ALLOCATED
ZPOOL_PROP_FREE
ZPOOL_PROP_FREEING
ZPOOL_PROP_EXPANDSZ
ZPOOL_PROP_ASHIFT
Also introduced is a wrapper function for zpool_get_prop making it
use zpool_get_prop_literal in the background.
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #1813
Currently there is no mechanism to inspect which dbufs are being
cached by the system. There are some coarse counters in arcstats
by they only give a rough idea of what's being cached. This patch
aims to improve the current situation by adding a new dbufs kstat.
When read this new kstat will walk all cached dbufs linked in to
the dbuf_hash. For each dbuf it will dump detailed information
about the buffer. It will also dump additional information about
the referenced arc buffer and its related dnode. This provides a
more complete view in to exactly what is being cached.
With this generic infrastructure in place utilities can be written
to post-process the data to understand exactly how the caching is
working. For example, the data could be processed to show a list
of all cached dnodes and how much space they're consuming. Or a
similar list could be generated based on dnode type. Many other
ways to interpret the data exist based on what kinds of questions
you're trying to answer.
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Prakash Surya <surya1@llnl.gov>
This change adds a new kstat to gain some visibility into the
amount of time spent in each call to dmu_tx_assign. A histogram
is exported via the new dmu_tx_assign file. The information
contained in this histogram is the frequency dmu_tx_assign
took to complete given an interval range.
Signed-off-by: Prakash Surya <surya1@llnl.gov>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
This change is an attempt to add visibility in to how txgs are being
formed on a system, in real time. To do this, a list was added to the
in memory SPA data structure for a pool, with each element on the list
corresponding to txg. These entries are then exported through the kstat
interface, which can then be interpreted in userspace.
For each txg, the following information is exported:
* Unique txg number (uint64_t)
* The time the txd was born (hrtime_t)
(*not* wall clock time; relative to the other entries on the list)
* The current txg state ((O)pen/(Q)uiescing/(S)yncing/(C)ommitted)
* The number of reserved bytes for the txg (uint64_t)
* The number of bytes read during the txg (uint64_t)
* The number of bytes written during the txg (uint64_t)
* The number of read operations during the txg (uint64_t)
* The number of write operations during the txg (uint64_t)
* The time the txg was closed (hrtime_t)
* The time the txg was quiesced (hrtime_t)
* The time the txg was synced (hrtime_t)
Note that while the raw kstat now stores relative hrtimes for the
open, quiesce, and sync times. Those relative times are used to
calculate how long each state took and these deltas and printed by
output handlers.
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
This change is an attempt to add visibility into the arc_read calls
occurring on a system, in real time. To do this, a list was added to the
in memory SPA data structure for a pool, with each element on the list
corresponding to a call to arc_read. These entries are then exported
through the kstat interface, which can then be interpreted in userspace.
For each arc_read call, the following information is exported:
* A unique identifier (uint64_t)
* The time the entry was added to the list (hrtime_t)
(*not* wall clock time; relative to the other entries on the list)
* The objset ID (uint64_t)
* The object number (uint64_t)
* The indirection level (uint64_t)
* The block ID (uint64_t)
* The name of the function originating the arc_read call (char[24])
* The arc_flags from the arc_read call (uint32_t)
* The PID of the reading thread (pid_t)
* The command or name of thread originating read (char[16])
From this exported information one can see, in real time, exactly what
is being read, what function is generating the read, and whether or not
the read was found to be already cached.
There is still some work to be done, but this should serve as a good
starting point.
Specifically, dbuf_read's are not accounted for in the currently
exported information. Thus, a follow up patch should probably be added
to export these calls that never call into arc_read (they only hit the
dbuf hash table). In addition, it might be nice to create a utility
similar to "arcstat.py" to digest the exported information and display
it in a more readable format. Or perhaps, log the information and allow
for it to be "replayed" at a later time.
Signed-off-by: Prakash Surya <surya1@llnl.gov>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
These kstat interfaces are required to port
"Illumos #3537 want pool io kstats" to ZFS on Linux.
kstat_waitq_enter()
kstat_waitq_exit()
kstat_runq_enter()
kstat_runq_exit()
Additionally, zero out the ks_data buffer in __kstat_create() so
that the kstat_io_t counters are initialized to zero.
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
While porting Illumos #3537 I found that ks_lock member of kstat_t
structure is different between Illumos and SPL. It is a pointer to
the kmutex_t in Illumos, but the mutex lock itself in SPL.
Apparently Illumos kstat API allows consumer to override the lock
if required. With SPL implementation it is not possible anymore.
Things were alright until the first attempt to actually override
the lock. Porting of Illumos #3537 introduced such code for the
first time.
In order to provide the Solaris/Illumos like functionality we:
1. convert ks_lock to "kmutex_t *ks_lock"
2. create a new field "kmutex_t ks_private_lock"
3. On kstat_create() ks_lock = &ks_private_lock
Thus if consumer doesn't care we still have our internal lock in use.
If, however, consumer does care she has a chance to set ks_lock to
anything else before calling kstat_install().
The rest of the code will use ks_lock regardless of its origin.
Signed-off-by: Ned Bass <bass6@llnl.gov>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #286
When creating a new pool, or adding/replacing a disk in an existing
pool, partition tables will be automatically created on the devices.
Under normal circumstances it will take less than a second for udev
to create the expected device files under /dev/. However, it has
been observed that if the system is doing heavy IO concurrently udev
may take far longer. If you also throw in some cheap dodgy hardware
it may take even longer.
To prevent zpool commands from failing due to this the default wait
time for udev is being increased to 30 seconds. This will have no
impact on normal usage, the increase timeout should only be noticed
if your udev rules are incorrectly configured.
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#1646
Linus Torvalds merged LZ4 into Linux 3.11. This causes a conflict
whenever CONFIG_LZ4_DECOMPRESS=y or CONFIG_LZ4_COMPRESS=y are set in the
kernel's .config. We rename the symbols to avoid the conflict.
Signed-off-by: Richard Yao <ryao@gentoo.org>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#1789
This reverts commit dba79fcbf2 in
favor of using the generic KSTAT_TYPE_RAW callbacks. The advantage
of this approach is that arbitrary types can be added without the
need to add them to the SPL.
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #296
This change adds simple wrappers for accessing a thread's PID and
command character string.
Signed-off-by: Prakash Surya <surya1@llnl.gov>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #296
The current implementation for displaying kstats of type KSTAT_TYPE_RAW
is rather crude. This patch attempts to enhance this handling by
allowing a kstat user to register formatting callbacks which can
optionally be used.
The callbacks allow the user to implement functions for interpreting
their data and transposing it into a character buffer. This buffer,
containing a string representation of the raw data, is then be displayed
through the current /proc textual interface.
Additionally the kstats are made writable because it's now possible
to provide a useful handler via the existing ks_update() interface.
Signed-off-by: Prakash Surya <surya1@llnl.gov>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #296
This is needed for the Illumos #4045 write throttle patch. It is used
in the arc eviction code to avoid blocking all arc activity by sitting on
arcs_mtx too long.
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #286
2882 implement libzfs_core
2883 changing "canmount" property to "on" should not always remount dataset
2900 "zfs snapshot" should be able to create multiple, arbitrary snapshots at once
Reviewed by: George Wilson <george.wilson@delphix.com>
Reviewed by: Chris Siden <christopher.siden@delphix.com>
Reviewed by: Garrett D'Amore <garrett@damore.org>
Reviewed by: Bill Pijewski <wdp@joyent.com>
Reviewed by: Dan Kruchinin <dan.kruchinin@gmail.com>
Approved by: Eric Schrock <Eric.Schrock@delphix.com>
References:
https://www.illumos.org/issues/2882https://www.illumos.org/issues/2883https://www.illumos.org/issues/2900illumos/illumos-gate@4445fffbbb
Ported-by: Tim Chase <tim@chase2k.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#1293
Porting notes:
WARNING: This patch changes the user/kernel ABI. That means that
the zfs/zpool utilities built from master are NOT compatible with
the 0.6.2 kernel modules. Ensure you load the matching kernel
modules from master after updating the utilities. Otherwise the
zfs/zpool commands will be unable to interact with your pool and
you will see errors similar to the following:
$ zpool list
failed to read pool configuration: bad address
no pools available
$ zfs list
no datasets available
Add zvol minor device creation to the new zfs_snapshot_nvl function.
Remove the logging of the "release" operation in
dsl_dataset_user_release_sync(). The logging caused a null dereference
because ds->ds_dir is zeroed in dsl_dataset_destroy_sync() and the
logging functions try to get the ds name via the dsl_dataset_name()
function. I've got no idea why this particular code would have worked
in Illumos. This code has subsequently been completely reworked in
Illumos commit 3b2aab1 (3464 zfs synctask code needs restructuring).
Squash some "may be used uninitialized" warning/erorrs.
Fix some printf format warnings for %lld and %llu.
Apply a few spa_writeable() changes that were made to Illumos in
illumos/illumos-gate.git@cd1c8b8 as part of the 3112, 3113, 3114 and
3115 fixes.
Add a missing call to fnvlist_free(nvl) in log_internal() that was added
in Illumos to fix issue 3085 but couldn't be ported to ZoL at the time
(zfsonlinux/zfs@9e11c73) because it depended on future work.
Commit torvalds/linux@2233f31aad
replaced ->readdir() with ->iterate() in struct file_operations.
All filesystems must now use the new ->iterate method.
To handle this the code was reworked to use the new ->iterate
interface. Care was taken to keep the majority of changes
confined to the ZPL layer which is already Linux specific.
However, minor changes were required to the common zfs_readdir()
function.
Compatibility with older kernels was accomplished by adding
versions of the trivial dir_emit* helper functions. Also the
various *_readdir() functions were reworked in to wrappers
which create a dir_context structure to pass to the new
*_iterate() functions.
Unfortunately, the new dir_emit* functions prevent us from
passing a private pointer to the filldir function. The xattr
directory code leveraged this ability through zfs_readdir()
to generate the list of xattr names. Since we can no longer
use zfs_readdir() a simplified zpl_xattr_readdir() function
was added to perform the same task.
Signed-off-by: Richard Yao <ryao@cs.stonybrook.edu>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#1653
Issue #1591
3618 ::zio dcmd does not show timestamp data
Reviewed by: Adam Leventhal <ahl@delphix.com>
Reviewed by: George Wilson <gwilson@zfsmail.com>
Reviewed by: Christopher Siden <christopher.siden@delphix.com>
Reviewed by: Garrett D'Amore <garrett@damore.org>
Approved by: Dan McDonald <danmcd@nexenta.com>
References:
http://www.illumos.org/issues/3618illumos/illumos-gate@c55e05cb35
Notes on porting to ZFS on Linux:
The original changeset mostly deals with mdb ::zio dcmd.
However, in order to provide the requested functionality
it modifies vdev and zio structures to keep the timing data
in nanoseconds instead of ticks. It is these changes that
are ported over in the commit in hand.
One visible change of this commit is that the default value
of 'zfs_vdev_time_shift' tunable is changed:
zfs_vdev_time_shift = 6
to
zfs_vdev_time_shift = 29
The original value of 6 was inherited from OpenSolaris and
was subotimal - since it shifted the raw tick value - it
didn't compensate for different tick frequencies on Linux and
OpenSolaris. The former has HZ=1000, while the latter HZ=100.
(Which itself led to other interesting performance anomalies
under non-trivial load. The deadline scheduler delays the IO
according to its priority - the lower priority the further
the deadline is set. The delay is measured in units of
"shifted ticks". Since the HZ value was 10 times higher,
the delay units were 10 times shorter. Thus really low
priority IO like resilver (delay is 10 units) and scrub
(delay is 20 units) were scheduled much sooner than intended.
The overall effect is that resilver and scrub IO consumed
more bandwidth at the expense of the other IO.)
Now that the bookkeeping is done is nanoseconds the shift
behaves correctly for any tick frequency (HZ).
Ported-by: Cyril Plisko <cyril.plisko@mountall.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#1643
Matthew Ahrens