Setting a limit on the minimum value of "arc_p" has been shown to have
detrimental effects on the arc hit rate for certain "metadata" intensive
workloads. Specifically, this has been exhibited with a workload that
constantly dirties new "metadata" but also frequently touches a "small"
amount of mfu data (e.g. mkdir's).
What is seen is that the new anon data throttles the mfu list to a
negligible size (because arc_p > anon + mru in arc_get_data_buf), even
though the mfu ghost list receives a constant stream of hits. To remedy
this, arc_p is now allowed to drop to zero if the algorithm deems it
necessary.
Signed-off-by: Prakash Surya <surya1@llnl.gov>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #2110
For specific workloads consisting mainly of mfu data and new anon data
buffers, the aggressive growth of arc_p found in the arc_get_data_buf()
function can have detrimental effects on the mfu list size and ghost
list hit rate.
Running a workload consisting of two processes:
* Process 1 is creating many small files
* Process 2 is tar'ing a directory consisting of many small files
I've seen arc_p and the mru grow to their maximum size, while the mru
ghost list receives 100K times fewer hits than the mfu ghost list.
Ideally, as the mfu ghost list receives hits, arc_p should be driven
down and the size of the mfu should increase. Given the specific
workload I was testing with, the mfu list size should grow to a point
where almost no mfu ghost list hits would occur. Unfortunately, this
does not happen because the newly dirtied anon buffers constancy drive
arc_p to its maximum value and keep it there (effectively prioritizing
the mru list and starving the mfu list down to a negligible size).
The logic to increment arc_p from within the arc_get_data_buf() function
was introduced many years ago in this upstream commit:
commit 641fbdae3a027d12b3c3dcd18927ccafae6d58bc
Author: maybee <none@none>
Date: Wed Dec 20 15:46:12 2006 -0800
6505658 target MRU size (arc.p) needs to be adjusted more aggressively
and since I don't fully understand the motivation for the change, I am
reluctant to completely remove it.
As a way to test out how it's removal might affect performance, I've
disabled that code by default, but left it tunable via a module option.
Thus, if its removal is found to be grossly detrimental for certain
workloads, it can be re-enabled on the fly, without a code change.
Signed-off-by: Prakash Surya <surya1@llnl.gov>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #2110
In an attempt to prevent arc_c from collapsing "too fast", the
arc_shrink() function was updated to take a "bytes" parameter by this
change:
commit 302f753f16
Author: Brian Behlendorf <behlendorf1@llnl.gov>
Date: Tue Mar 13 14:29:16 2012 -0700
Integrate ARC more tightly with Linux
Unfortunately, that change failed to make a similar change to the way
that arc_p was updated. So, there still exists the possibility for arc_p
to collapse to near 0 when the kernel start calling the arc's shrinkers.
This change attempts to fix this, by decrementing arc_p by the "bytes"
parameter in the same way that arc_c is updated.
In addition, a minimum value of arc_p is attempted to be maintained,
similar to the way a minimum arc_p value is maintained in arc_adapt().
Signed-off-by: Prakash Surya <surya1@llnl.gov>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #2110
Decrease the mimimum ARC size from 1/32 of total system memory
(or 64MB) to a much smaller 4MB.
1) Large systems with over a 1TB of memory are being deployed
and reserving 1/32 of this memory (32GB) as the mimimum
requirement is overkill.
2) Tiny systems like the raspberry pi may only have 256MB of
memory in which case 64MB is far too large.
The ARC should be reclaimable if the VFS determines it needs
the memory for some other purpose. If you want to ensure the
ARC is never completely reclaimed due to memory pressure you
may still set a larger value with zfs_arc_min.
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Prakash Surya <surya1@llnl.gov>
Issue #2110
ZoL commit 1421c89 unintentionally changed the disk format in a forward-
compatible, but not backward compatible way. This was accomplished by
adding an entry to zbookmark_t, which is included in a couple of
on-disk structures. That lead to the creation of pools with incorrect
dsl_scan_phys_t objects that could only be imported by versions of ZoL
containing that commit. Such pools cannot be imported by other versions
of ZFS or past versions of ZoL.
The additional field has been removed by the previous commit. However,
affected pools must be imported and scrubbed using a version of ZoL with
this commit applied. This will return the pools to a state in which they
may be imported by other implementations.
The 'zpool import' or 'zpool status' command can be used to determine if
a pool is impacted. A message similar to one of the following means your
pool must be scrubbed to restore compatibility.
$ zpool import
pool: zol-0.6.2-173
id: 1165955789558693437
state: ONLINE
status: Errata #1 detected.
action: The pool can be imported using its name or numeric identifier,
however there is a compatibility issue which should be corrected
by running 'zpool scrub'
see: http://zfsonlinux.org/msg/ZFS-8000-ER
config:
...
$ zpool status
pool: zol-0.6.2-173
state: ONLINE
scan: pool compatibility issue detected.
see: https://github.com/zfsonlinux/zfs/issues/2094
action: To correct the issue run 'zpool scrub'.
config:
...
If there was an async destroy in progress 'zpool import' will prevent
the pool from being imported. Further advice on how to proceed will be
provided by the error message as follows.
$ zpool import
pool: zol-0.6.2-173
id: 1165955789558693437
state: ONLINE
status: Errata #2 detected.
action: The pool can not be imported with this version of ZFS due to an
active asynchronous destroy. Revert to an earlier version and
allow the destroy to complete before updating.
see: http://zfsonlinux.org/msg/ZFS-8000-ER
config:
...
Pools affected by the damaged dsl_scan_phys_t can be detected prior to
an upgrade by running the following command as root:
zdb -dddd poolname 1 | grep -P '^\t\tscan = ' | sed -e 's;scan = ;;' | wc -w
Note that `poolname` must be replaced with the name of the pool you wish
to check. A value of 25 indicates the dsl_scan_phys_t has been damaged.
A value of 24 indicates that the dsl_scan_phys_t is normal. A value of 0
indicates that there has never been a scrub run on the pool.
The regression caused by the change to zbookmark_t never made it into a
tagged release, Gentoo backports, Ubuntu, Debian, Fedora, or EPEL
stable respositorys. Only those using the HEAD version directly from
Github after the 0.6.2 but before the 0.6.3 tag are affected.
This patch does have one limitation that should be mentioned. It will not
detect errata #2 on a pool unless errata #1 is also present. It expected
this will not be a significant problem because pools impacted by errata #2
have a high probably of being impacted by errata #1.
End users can ensure they do no hit this unlikely case by waiting for all
asynchronous destroy operations to complete before updating ZoL. The
presence of any background destroys on any imported pools can be checked
by running `zpool get freeing` as root. This will display a non-zero
value for any pool with an active asynchronous destroy.
Lastly, it is expected that no user data has been lost as a result of
this erratum.
Original-patch-by: Tim Chase <tim@chase2k.com>
Reworked-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Tim Chase <tim@chase2k.com>
Signed-off-by: Richard Yao <ryao@gentoo.org>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #2094
From time to time it may be necessary to inform the pool administrator
about an errata which impacts their pool. These errata will by shown
to the administrator through the 'zpool status' and 'zpool import'
output as appropriate. The errata must clearly describe the issue
detected, how the pool is impacted, and what action should be taken
to resolve the situation. Additional information for each errata will
be provided at http://zfsonlinux.org/msg/ZFS-8000-ER.
To accomplish the above this patch adds the required infrastructure to
allow the kernel modules to notify the utilities that an errata has
been detected. This is done through the ZPOOL_CONFIG_ERRATA uint64_t
which has been added to the pool configuration nvlist.
To add a new errata the following changes must be made:
* A new errata identifier must be assigned by adding a new enum value
to the zpool_errata_t type. New enums must be added to the end to
preserve the existing ordering.
* Code must be added to detect the issue. This does not strictly
need to be done at pool import time but doing so will make the
errata visible in 'zpool import' as well as 'zpool status'. Once
detected the spa->spa_errata member should be set to the new enum.
* If possible code should be added to clear the spa->spa_errata member
once the errata has been resolved.
* The show_import() and status_callback() functions must be updated
to include an informational message describing the errata. This
should include an action message describing what an administrator
should do to address the errata.
* The documentation at http://zfsonlinux.org/msg/ZFS-8000-ER must be
updated to describe the errata. This space can be used to provide
as much additional information as needed to fully describe the errata.
A link to this documentation will be automatically generated in the
output of 'zpool import' and 'zpool status'.
Original-idea-by: Tim Chase <tim@chase2k.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Tim Chase <tim@chase2k.com>
Signed-off-by: Richard Yao <ryao@gentoo.or
Issue #2094
Commit 1421c89142 added a field to
zbookmark_t that unintentinoally caused a disk format change. This
negatively affected backward compatibility and platform portability.
Therefore, this field is being removed.
The function that field permitted is left unimplemented until a later
patch that will reimplement the field in a way that does not affect the
disk format.
Signed-off-by: Richard Yao <ryao@gentoo.org>
Signed-off-by: Tim Chase <tim@chase2k.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #2094
Various errors can occur when registering property callbacks. As the
author's comments indicate, the code is very paranoid about preserving
the first-seen error when registering callbacks. This patch causes an
error seen while registering the "relatime" callback to not clobber a
previously-seen error.
Reported-by: Jorgen Lundman <lundman@lundman.net>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#2117
Commit e0b0ca9 accidentally corrupted the l2_asize displayed in
arcstats. This was caused by changing the l2arc_buf_hdr.b_asize
member from an int to uint32_t type. There are places in the
code where this field is cast to a uint64_t resulting in the
b_hits member being treated as part of b_asize.
To resolve the issue the type has been changed to a uint64_t,
and the b_hits member is placed after the enum to prevent the
size of the structure from increasing.
This is a good example of exactly why it's a bad idea to use
ambiguous types (int) in these structures.
Signed-off-by: DHE <git@dehacked.net>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#1990
Reviewed by: George Wilson <george.wilson@delphix.com>
Reviewed by: Christopher Siden <christopher.siden@delphix.com>
Approved by: Garrett D'Amore <garrett@damore.org>
Refences:
https://www.illumos.org/issues/4188illumos/illumos-gate@bb411a08b0
Ported-by: Chris Dunlop <chris@onthe.net.au>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#2091
Add the "relatime" property. When set to "on", a file's atime will only
be updated if the existing atime at least a day old or if the existing
ctime or mtime has been updated since the last access. This behavior
is compatible with the Linux "relatime" mount option.
Signed-off-by: Tim Chase <tim@chase2k.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#2064Closes#1917
When transitioning current open TXG into QUIESCE state and opening
a new one txg_quiesce() calls gethrtime():
- to mark the birth time of the new TXG
- to record the SPA txg history kstat
- implicitely inside spa_txg_history_add()
These timestamps are practically the same, so that the first one
can be used instead of the other two. The only visible difference
is that inside spa_txg_history_add() the time spent in kmem_zalloc()
will be counted towards the opened TXG.
Since at this point the new TXG already exists (tx->tx_open_txg
has been already incremented) it is actually a correct accounting.
In any case this extra work is only happening when spa_txg_history
kstat is activated (i.e. zfs_txg_history > 0) and doesn't affect
the normal processing in any way.
Signed-off-by: Cyril Plisko <cyril.plisko@mountall.com>
Issue #2075
In several cases when digging into kstats we can found two txgs
in SYNC state, e.g.
txg birth state nreserved nread nwritten ...
985452 258127184872561 C 0 373948416 2376272384 ...
985453 258129016180616 C 0 378173440 28793344 ...
985454 258129016271523 S 0 0 0 ...
985455 258130864245986 S 0 0 0 ...
985456 258130867458851 O 0 0 0 ...
However only first txg (985454) is really syncing at this moment.
The other one (985455) marked as SYNCED is actually in a post-QUIESCED
state and waiting to start sync. So, the new TXG_STATE_WAIT_FOR_SYNC
state between TXG_STATE_QUIESCED and TXG_STATE_SYNCED was added to
reveal this situation.
txg birth state nreserved nread nwritten ...
1086896 235261068743969 C 0 163577856 8437248 ...
1086897 235262870830801 C 0 280625152 822594048 ...
1086898 235264172219064 S 0 0 0 ...
1086899 235264936134407 W 0 0 0 ...
1086900 235264936296156 O 0 0 0 ...
Signed-off-by: Igor Lvovsky <ilvovsky@gmail.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #2075
From the comment in the commit:
Some ZFS implementations (ZEVO) create neither a ZNODE_ACL nor a DACL_ACES
SA in which case ENOENT is returned from zfs_acl_node_read() when the
SA can't be located. Allow chown/chgrp to succeed in these cases rather
than returning an error that makes no sense in the context of the caller.
Signed-off-by: Tim Chase <tim@chase2k.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue zfs-osx/zfs#86
Closes#1911Closes#2029
The vdev_file_io_start() function may be processing a zio that the
txg_sync thread is waiting on. In this case it is not safe to perform
memory allocations that may generate new I/O since this could cause a
deadlock. To avoid this, call taskq_dispatch() with TQ_PUSHPAGE
instead of TQ_SLEEP.
Signed-off-by: Ned Bass <bass6@llnl.gov>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #1928
Under Linux the zvol_set_volsize() function was originally written
to use dmu_objset_hold()/dmu_objset_rele(). Subsequently, the
dmu_objset_own()/dmu_objset_disown() interfaces were added but
the ZVOL code wasn't updated to take advantage of them.
This was never an issue but after the dsl_pool_config changes
the code now takes the config lock twice. The cleanest solution
is to shift to using dmu_objset_own() which takes a long hold
on the dataset and does not hold the dsl pool lock.
This patch also slightly restructures the existing code such
that it more closely resembles the upstream Illumos code.
Signed-off-by: Ned Bass <bass6@llnl.gov>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#2039
It's unsafe to drain the iput taskq while holding the z_teardown_lock
as a writer. This is because when the last reference on an inode is
dropped it may still have pages which need to be written to disk.
This will be done through zpl_writepages which will acquire the
z_teardown_lock as a reader in ZFS_ENTER. Therefore, if we're
holding the lock as a writer in zfs_sb_teardown the unmount will
deadlock.
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Chris Dunlop <chris@onthe.net.au>
Closes#1988
This change was proposed for Sparc but it's not clear to me
why it's required. Proper support exists in the lz4 code to
detect the endianness and the required builtins are available
for gcc. Still I'm including the patch because it will only
impact Sparc and it may resolve a case which hasn't occured
to me.
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Ned Bass <bass6@llnl.gov>
Signed-off-by: marku89 <mar42@kola.li>
Issue #1700
On Sparc sp->blksize will be a 64-bit value which is then cast
incorrectly to a 32-bit value. For big endian systems this
results in an incorrect value for sp->blksize. To resolve the
problem local variables of the correct size are used and then
assigned to sp->blksize.
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Ned Bass <bass6@llnl.gov>
Signed-off-by: marku89 <mar42@kola.li>
Issue #1700
When accessing the zp->z_mode through the SA bulk interface we
expect that 64-bits are available to hold the result. However,
on 32-bit platforms mode_t will only be 32-bits so we cannot
pass it to SA_ADD_BULK_ATTR(). Instead a local uint64_t variable
must be used and the result assigned to zp->z_mode.
This went unnoticed on 32-bit little endian platforms because
the bytes happen to end up in the correct 32-bits. But on big
endian platforms like Sparc the zp->z_mode will always end up
set to zero.
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Ned Bass <bass6@llnl.gov>
Signed-off-by: marku89 <mar42@kola.li>
Issue #1700
Back the allocations for ddt tables+entries and l2arc headers with
kmem caches. This will reduce the cost of allocating these commonly
used structures and allow for greater visibility of them through the
/proc/spl/kmem/slab interface.
Signed-off-by: John Layman <jlayman@sagecloud.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#1893
Move the libzfs_fini() after the zpool_log_history() call so the
ZPOOL_HIST_CMD entry can get written.
Fix the handling of saved_poolname in zfsdev_ioctl()
which was broken as part of the stack-reduction work in
a168788053.
Since ZoL destroys the TSD data in which the previously successful
ioctl()'s pool name is stored following every vop, the ZFS_IOC_LOG_HISTORY
ioctl has a very important restriction: it can only successfully write
a long entry following a successful ioctl() if no intervening vops have
been performed. Some of zfs subcommands do perform intervening vops and
to do the logging themselves. At the moment, the "create" and "clone"
subcommands have been modified appropriately.
Signed-off-by: Tim Chase <tim@chase2k.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#1998
During the update process in sa_modify_attrs(), the sizes of existing
variably-sized SA entries are obtained from sa_lengths[]. The case where
a variably-sized SA was being replaced neglected to increment the index
into sa_lengths[], so subsequent variable-length SAs would be rewritten
with the wrong length. This patch adds the missing increment operation
so all variably-sized SA entries are stored with their correct lengths.
Previously, a size-changing update of a variably-sized SA that occurred
when there were other variably-sized SAs in the bonus buffer would cause
the subsequent SAs to be corrupted. The most common case in which this
would occur is when a mode change caused the ZPL_DACL_ACES entry to
change size when a ZPL_DXATTR (SA xattr) entry already existed.
The following sequence would have caused a failure when xattr=sa was in
force and would corrupt the bonus buffer:
open(filename, O_WRONLY | O_CREAT, 0600);
...
lsetxattr(filename, ...); /* create xattr SA */
chmod(filename, 0650); /* enlarges the ACL */
Signed-off-by: Chris Dunlop <chris@onthe.net.au>
Signed-off-by: Ned Bass <bass6@llnl.gov>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#1978
The vast majority of these changes are in Linux specific code.
They are the result of not having an automated style checker to
validate the code when it was originally written. Others were
caused when the common code was slightly adjusted for Linux.
This patch contains no functional changes. It only refreshes
the code to conform to style guide.
Everyone submitting patches for inclusion upstream should now
run 'make checkstyle' and resolve any warning prior to opening
a pull request. The automated builders have been updated to
fail a build if when 'make checkstyle' detects an issue.
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#1821
The comment in zfs_close states that "Under Linux the zfs_close() hook
is not symmetric with zfs_open()". This is not true. zfs_open/zfs_close
is associated with every successful struct file creation/deletion, which
should always be balanced.
Here is an example of what's wrong:
Process A B
open(O_SYNC)
z_sync_cnt = 1
open(O_SYNC)
z_sync_cnt = 2
close()
z_sync_cnt = 0
So z_sync_cnt is 0 even if B still has the file with O_SYNC.
Also moves the generic_file_open call before zfs_open to ensure that in
the case generic_file_open fails z_sync_cnt is not incremented. This
is safe because generic_file_open has no side effects.
Signed-off-by: Chunwei Chen <tuxoko@gmail.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #1962
Update zvol.c to conform to the style guidelines, verified by
running cstyle.pl on the source file. This patch contains
no functional changes.
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Ned Bass <bass6@llnl.gov>
Signed-off-by: Tim Chase <tim@chase2k.com>
Issue #1821
In order to minimize any future disruption caused by the addition
and removal /dev/zfs ioctls this patch makes the following changes.
1) Sync ZoL's ioctl ordering such that it matches Illumos. For
historic reasons the ZFS_IOC_DESTROY_SNAPS and ZFS_IOC_POOL_REGUID
ioctls were out of order.
2) Move Linux and FreeBSD specific ioctls in to their own reserved
ranges. This allows us to preserve the existing ordering when
new ioctls are added by either Illumos or FreeBSD. When an
ioctl is no longer needed it should be retired in place.
This change alters the ZFS user/kernel ABI so make sure you rebuild
both your user and kernel modules. However, it should allow for a
much stabler interface going forward.
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Ned Bass <bass6@llnl.gov>
Closes#1973
Early versions of ZFS coordinated the creation and destruction
of device minors from userspace. This was inherently racy and
in late 2009 these ioctl()s were removed leaving everything up
to the kernel. This significantly simplified the code.
However, we never picked up these changes in ZoL since we'd
already significantly adjusted this code for Linux. This patch
aims to rectify that by finally removing ZFC_IOC_*_MINOR ioctl()s
and moving all the functionality down in to the kernel. Since
this cleanup will change the kernel/user ABI it's being done
in the same tag as the previous libzfs_core ABI changes. This
will minimize, but not eliminate, the disruption to end users.
Once merged ZoL, Illumos, and FreeBSD will basically be back
in sync in regards to handling ZVOLs in the common code. While
each platform must have its own custom zvol.c implemenation the
interfaces provided are consistent.
NOTES:
1) This patch introduces one subtle change in behavior which
could not be easily avoided. Prior to this change callers
of 'zfs create -V ...' were guaranteed that upon exit the
/dev/zvol/ block device link would be created or an error
returned. That's no longer the case. The utilities will no
longer block waiting for the symlink to be created. Callers
are now responsible for blocking, this is why a 'udev_wait'
call was added to the 'label' function in scripts/common.sh.
2) The read-only behavior of a ZVOL now solely depends on if
the ZVOL_RDONLY bit is set in zv->zv_flags. The redundant
policy setting in the gendisk structure was removed. This
both simplifies the code and allows us to safely leverage
set_disk_ro() to issue a KOBJ_CHANGE uevent. See the
comment in the code for futher details on this.
3) Because __zvol_create_minor() and zvol_alloc() may now be
called in a sync task they must use KM_PUSHPAGE.
References:
illumos/illumos-gate@681d9761e8
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Ned Bass <bass6@llnl.gov>
Signed-off-by: Tim Chase <tim@chase2k.com>
Closes#1969
4121 vdev_label_init should treat request as succeeded when pool
is read only
Reviewed by: Christopher Siden <christopher.siden@delphix.com>
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Reviewed by: Saso Kiselkov <skiselkov.ml@gmail.com>
Approved by: Richard Lowe <richlowe@richlowe.net>
References:
https://www.illumos.org/issues/4121illumos/illumos-gate@973c78e94b
Ported-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#1863
Previously, the atime-modifying vnops called ZFS_ACCESSTIME_STAMP()
followed by zfs_inode_update() to update the atime. However, since atimes
are cached in the znode for delayed writing, the zfs_inode_update()
function would effectively ignore the cached atime by reading it from
the SA.
This commit moves the updating of the atime in the inode into
zfs_tstamp_update_setup() which is called by the ZFS_ACCESSTIME_STAMP()
macro and eliminates the call to zfs_inode_update() in the atime-modifying
vnops.
It's possible the same thing could have been done directly in
zfs_inode_update() but I wasn't sure that it was safe in all cases where
it is called.
The effect is that atime handling is as if "strictatime" were selected;
even if the filesystem is mounted with "relatime".
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #1949
The MAX when initializing arc_c_max doesn't make any sense because
it hasn't been set anywhere before. Though, arc_c_max should be
implicitly set to zero when initializing arc_stats, so the MAX
doesn't make any difference.
The MAX was mistakenly left if place when the Illumos default
values were changed for Linux.
Signed-off-by: david.chen <tuxoko@gmail.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#1941
This reverts commit 6a7c0ccca4.
A proper fix for Issue #1648 was landed under Issue #1890, so this is no
longer needed.
Signed-off-by: Ned Bass <bass6@llnl.gov>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#1648
Under the right conditions sa_find_sizes() will compute an incorrect
size of the system attribute (SA) header. This causes a failed assertion
when the SA_HDR_SIZE_MATCH_LAYOUT() test returns false, and may lead
to corruption of SA data.
The bug presents itself when there are more than two variable-length SAs
of just the right size to fit in the bonus buffer of a dnode. The
existing logic fails to account for the SA header space needed to store
the sizes of all the variable-length SAs.
A reproducer was possible on Linux by setting the xattr=sa dataset
property and storing xattrs on symbolic links (Issue #1648). Note the
corrupt link target name:
$ zfs set xattr=sa tank/fish
$ cd /tank/fish
$ ln -fs 12345678901234567 link
$ setfattr -n trusted.0000000000000000000 -v 0x000000000000000000000000 -h link
$ setfattr -n trusted.1111111111111111111 -v 0x000000000000000000000000 -h link
$ ls -l link
lrwxrwxrwx 1 root root 17 Dec 6 15:40 link -> 90123456701234567
Commit 6a7c0ccca4 worked around this bug
by forcing xattr's on symlinks to be stored in directory format. This
change implements a proper fix, so the workaround can now be reverted.
The reference link below contains a reproducer for FreeBSD.
References:
http://lists.open-zfs.org/pipermail/developer/2013-November/000306.html
Ported-by: Ned Bass <bass6@llnl.gov>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#1890
When creating a dataset with ZoL a zsb->z_shares_dir ZAP object
will not be created because shares are unimplemented. Instead ZoL
just sets zsb->z_shares_dir to zero to indicate there are no shares.
However, if you import a pool which was created with a different
ZFS implementation then the shares ZAP object may exist. Code was
added to handle this case but it clearly wasn't sufficiently tested
with other ZFS pools.
There was a bug in the zpl_shares_getattr() function which passed
the wrong inode to zfs_getattr_fast() for the case where are shares
ZAP object does exist. This causes an EIO to be returned to stat64()
which in turn causes 'zfs diff' to fail.
This fix is the pass the correct inode after a sucessful zfs_zget().
Additionally, only put away the references if we were able to get one.
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Graham Booker <https://github.com/gbooker>
Signed-off-by: timemaster67 <https://github.com/timemaster67>
Closes#1426Closes#481
Use the standard Linux MODULE_VERSION macro to expose the installed
zavl, znvpair, zunicode, zcommon, zfs, and zpios module versions.
This will also automatically add a checksum of the .c files and
headers in "srcversion". See:
/sys/module/zavl/version
/sys/module/zavl/srcversion
/sys/module/znvpair/version
/sys/module/znvpair/srcversion
/sys/module/zunicode/version
/sys/module/zunicode/srcversion
/sys/module/zcommon/version
/sys/module/zcommon/srcversion
/sys/module/zfs/version
/sys/module/zfs/srcversion
/sys/module/zpios/version
/sys/module/zpios/srcversion
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#1923
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
Fix a lock contention issue by allowing threads not holding
ZPL locks to block when waiting to assign a transaction.
Porting Notes:
zfs_putpage() still uses TXG_NOWAIT, unlike the upstream version. This
case may be a contention point just like zfs_write(), however it is not
safe to block here since it may be called during memory reclaim.
Reviewed by: George Wilson <george.wilson@delphix.com>
Reviewed by: Adam Leventhal <ahl@delphix.com>
Reviewed by: Dan McDonald <danmcd@nexenta.com>
Reviewed by: Boris Protopopov <boris.protopopov@nexenta.com>
Approved by: Dan McDonald <danmcd@nexenta.com>
References:
https://www.illumos.org/issues/4347illumos/illumos-gate@e722410c49
Ported-by: Ned Bass <bass6@llnl.gov>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
As part of zfs_sb_teardown() there is an assertion that all inodes
which are part of the zsb->z_all_znodes list have at least one
reference on them. This is always true for the standard unmount
case but there are two other cases where it is not strictly true.
* zfs_ioc_rollback() - This is the most common case and it results
from the fact that we aren't unmounting the filesystem. During a
normal unmount the MS_ACTIVE flag will be cleared on the super block
causing iput_final() to evict the inode when its reference count
drops to zero. However, during a rollback MS_ACTIVE remains set
since we're rolling back a live filesystem and need to preserve the
existing super block. This allows inodes with a zero reference count
to stay in the cache thereby violating the assertion.
* destroy_inode() / zfs_sb_teardown() - There exists a small race
between dropping the last reference on an inode and removing it from
the zsb->z_all_znodes list. This is unlikely to occur but could also
trigger the assertion which is incorrect. The inode may safely have
a zero reference count in this case.
Since allowing a zero reference count on the inode is expected and
safe for both of these cases the simplest thing to do is remove the
ASSERT. This code is only enabled for default builds so removing
this entirely is a very safe change.
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Chris Dunlop <chris@onthe.net.au>
Signed-off-by: Tim Chase <tim@chase2k.com>
Closes#1417Closes#1536
This should hopefully catch the rest of the allocations in the
user hold/release processing that were missed by commit
65c67ea86e.
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#1852Closes#1855
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
Under Linux this restriction does not apply because we have access
to all the required devices.
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#1631
Properly initialize SELinux xattrs for all inode types. The
initial implementation accidentally only did this for files.
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#1832
During pool import stack overflows may still occur due to the
potentially deep recursion of traverse_visitbp(). This is most
likely to occur when additional layers are added to the block
device stack such as DM multipath. To minimize the stack usage
for this call path the following changes were made:
1) Added the keywork 'noinline' to the vdev_*_map_alloc() functions
to prevent them from being inlined by gcc. This reduced the
stack usage of vdev_raidz_io_start() from 208 to 128 bytes, and
vdev_mirror_io_start() from 144 to 128 bytes.
2) The 'saved_poolname' charater array in zfsdev_ioctl() was moved
from the stack to the heap. This reduced the stack usage of
zfsdev_ioctl() from 368 to 112 bytes.
3) The major saving came from slimming down traverse_visitbp() from
from 224 to 144 bytes. Since this function is called recursively
the 80 bytes saved per invokation adds up. The following changes
were made:
a) The 'hard' local variable was replaced by a TD_HARD() macro.
b) The 'pd' local variable was replaced by 'td->td_pfd' references.
c) The zbookmark_t was moved to the heap. This does cost us an
additional memory allocation per recursion by that cost should
still be minimal. The cost could be further reduced by adding
a dedicated zbookmark_t slab cache.
d) The variable declarations in 'if (BP_GET_LEVEL()) { }' were
restructured to use the minimum amount of stack. This includes
removing the 'cbp' local variable.
Overall for the offending use case roughly 1584 of total stack space
has been saved. This is enough to avoid overflowing the stack on
stock kernels with 8k stacks. See #1778 for additional details.
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Ned Bass <bass6@llnl.gov>
Closes#1778
Commit 95fd54a1c5 restructured the
hold/release processing and moved some of the work into the sync task.
A number of nvlist allocations now need to use KM_PUSHPAGE.
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#1852Closes#1855
The Illumos #3875 patch reverted a part of ZoL's 7b3e34b which added
special-case error handling for zfs_rezget(). The error handling dealt
with the case in which an all-ones object number ended up being passed
to dnode_hold() and causing an EINVAL to be returned from zfs_rezget().
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#1859Closes#1861
In the current snapshot automount implementation, it is possible for
multiple mounts to attempted concurrently. Only one of the mounts will
succeed and the other will fail. The failed mounts will cause an EREMOTE
to be propagated back to the application.
This commit works around the problem by adding a new exit status,
MOUNT_BUSY to the mount.zfs program which is used when the underlying
mount(2) call returns EBUSY. The zfs code detects this condition and
treats it as if the mount had succeeded.
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#1819
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
A couple of kmem_alloc() allocations were using KM_SLEEP in
the sync thread context. These were accidentally introduced
by the recent set of Illumos patches. The solution is to
switch to KM_PUSHPAGE.
dsl_dataset_promote_sync() -> promote_hold() -> snaplist_make() ->
kmem_alloc(sizeof (*snap), KM_SLEEP);
dsl_dataset_user_hold_sync() -> dsl_onexit_hold_cleanup() ->
kmem_alloc(sizeof (*ca), KM_SLEEP)
Signed-off-by: Richard Yao <ryao@gentoo.org>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #1775
3995 Memory leak of compressed buffers in l2arc_write_done
References:
https://illumos.org/issues/3995
Ported-by: Richard Yao <ryao@gentoo.org>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#1688
Issue #1775
4168 ztest assertion failure in dbuf_undirty
4169 verbatim import causes zdb to segfault
4170 zhack leaves pool in ACTIVE state
Reviewed by: Adam Leventhal <ahl@delphix.com>
Reviewed by: Eric Schrock <eric.schrock@delphix.com>
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Approved by: Dan McDonald <danmcd@nexenta.com>
References:
https://www.illumos.org/issues/4168https://www.illumos.org/issues/4169https://www.illumos.org/issues/4170illumos/illumos-gate@7fdd916c47
Ported-by: Richard Yao <ryao@gentoo.org>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #1775
4082 zfs receive gets EFBIG from dmu_tx_hold_free()
Reviewed by: Eric Schrock <eric.schrock@delphix.com>
Reviewed by: Christopher Siden <christopher.siden@delphix.com>
Reviewed by: George Wilson <george.wilson@delphix.com>
Approved by: Richard Lowe <richlowe@richlowe.net>
References:
https://www.illumos.org/issues/4082illumos/illumos-gate@5253393b09
Ported-by: Richard Yao <ryao@gentoo.org>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #1775
4046 dsl_dataset_t ds_dir->dd_lock is highly contended
Reviewed by: Eric Schrock <eric.schrock@delphix.com>
Reviewed by: George Wilson <george.wilson@delphix.com>
Approved by: Garrett D'Amore <garrett@damore.org>
References:
https://www.illumos.org/issues/4046illumos/illumos-gate@b62969f868
Ported-by: Richard Yao <ryao@gentoo.org>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #1775
Porting notes:
1. This commit removed dsl_dataset_namelen in Illumos, but that
appears to have been removed from ZFSOnLinux in an earlier commit.
4047 panic from dbuf_free_range() from dmu_free_object() while
doing zfs receive
Reviewed by: Adam Leventhal <ahl@delphix.com>
Reviewed by: George Wilson <george.wilson@delphix.com>
Approved by: Dan McDonald <danmcd@nexenta.com>
References:
https://www.illumos.org/issues/4047illumos/illumos-gate@713d6c2088
Ported-by: Richard Yao <ryao@gentoo.org>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #1775
Porting notes:
1. The exported symbol dmu_free_object() was renamed to
dmu_free_long_object() in Illumos.
3996 want a libzfs_core API to rollback to latest snapshot
Reviewed by: Christopher Siden <christopher.siden@delphix.com>
Reviewed by: Adam Leventhal <ahl@delphix.com>
Reviewed by: George Wilson <george.wilson@delphix.com>
Reviewed by: Andy Stormont <andyjstormont@gmail.com>
Approved by: Richard Lowe <richlowe@richlowe.net>
References:
https://www.illumos.org/issues/3996illumos/illumos-gate@a7027df17f
Ported-by: Richard Yao <ryao@gentoo.org>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #1775
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.
3949 ztest fault injection should avoid resilvering devices
3950 ztest: deadman fires when we're doing a scan
3951 ztest hang when running dedup test
3952 ztest: ztest_reguid test and ztest_fault_inject don't place nice together
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/3949https://www.illumos.org/issues/3950https://www.illumos.org/issues/3951https://www.illumos.org/issues/3952illumos/illumos-gate@2c1e2b4414
Ported-by: Richard Yao <ryao@gentoo.org>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #1775
Porting notes:
1. The deadman thread was removed from ztest during the original
port because it depended on Solaris thr_create() interface.
This functionality should be reintroduced using the more
portable pthreads.
3973 zfs_ioc_rename alters passed in zc->zc_name
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Reviewed by: George Wilson <george.wilson@delphix.com>
Approved by: Christopher Siden <christopher.siden@delphix.com>
References:
https://www.illumos.org/issues/3973illumos/illumos-gate@a0c1127b14
Ported-by: Richard Yao <ryao@gentoo.org>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #1775
3834 incremental replication of 'holey' file systems is slow
Reviewed by: Adam Leventhal <ahl@delphix.com>
Reviewed by: George Wilson <george.wilson@delphix.com>
Approved by: Richard Lowe <richlowe@richlowe.net>
References:
https://www.illumos.org/issues/3834illumos/illumos-gate@ca48f36f20
Ported-by: Richard Yao <ryao@gentoo.org>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #1775
3836 zio_free() can be processed immediately in the common case
Reviewed by: George Wilson <george.wilson@delphix.com>
Reviewed by: Adam Leventhal <ahl@delphix.com>
Approved by: Dan McDonald <danmcd@nexenta.com>
References:
https://www.illumos.org/issues/3836illumos/illumos-gate@9cb154a3c9
Ported-by: Richard Yao <ryao@gentoo.org>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #1775
3112 ztest does not honor ZFS_DEBUG
3113 ztest should use watchpoints to protect frozen arc bufs
3114 some leaked nvlists in zfsdev_ioctl
Reviewed by: Adam Leventhal <ahl@delphix.com>
Reviewed by: Matt Amdur <Matt.Amdur@delphix.com>
Reviewed by: George Wilson <george.wilson@delphix.com>
Reviewed by: Christopher Siden <chris.siden@delphix.com>
Approved by: Eric Schrock <eric.schrock@delphix.com>
References:
https://www.illumos.org/issues/3112https://www.illumos.org/issues/3113https://www.illumos.org/issues/3114illumos/illumos-gate@cd1c8b85eb
The /proc/self/cmd watchpoint interface is specific to Solaris.
Therefore, the #3113 implementation was reworked to use the more
portable mprotect(2) system call. When the pages are watched they
are marked read-only for protection. Any write to the protected
address range immediately trigger a SIGSEGV. The pages are marked
writable again when they are unwatched.
Ported-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #1489
3236 zio nop-write
Reviewed by: Matt Ahrens <matthew.ahrens@delphix.com>
Reviewed by: Adam Leventhal <ahl@delphix.com>
Reviewed by: Christopher Siden <chris.siden@delphix.com>
Approved by: Garrett D'Amore <garrett@damore.org>
References:
illumos/illumos-gate@80901aea8ehttps://www.illumos.org/issues/3236
Porting Notes
1. This patch is being merged dispite an increased instance of
https://www.illumos.org/issues/3113 being triggered by ztest.
Ported-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #1489
3875 panic in zfs_root() after failed rollback
Reviewed by: Jerry Jelinek <jerry.jelinek@joyent.com>
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Approved by: Gordon Ross <gwr@nexenta.com>
References:
https://www.illumos.org/issues/3875illumos/illumos-gate@91948b51b8
Ported-by: Richard Yao <ryao@gentoo.org>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #1775
3888 zfs recv -F should destroy any snapshots created since
the incremental source
Reviewed by: George Wilson <george.wilson@delphix.com>
Reviewed by: Adam Leventhal <ahl@delphix.com>
Reviewed by: Peng Dai <peng.dai@delphix.com>
Approved by: Richard Lowe <richlowe@richlowe.net>
References:
https://www.illumos.org/issues/3888illumos/illumos-gate@34f2f8cf94
Porting notes:
1. Commit 1fde1e3720 wrapped a
declaration in dsl_dataset_modified_since_lastsnap in ASSERTV().
The ASSERTV() and local variable have been removed to avoid an
unused variable warning.
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Ported-by: Richard Yao <ryao@gentoo.org>
Issue #1775
3894 zfs should not allow snapshot of inconsistent dataset
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Approved by: Gordon Ross <gwr@nexenta.com>
References:
https://www.illumos.org/issues/3894illumos/illumos-gate@ca48f36f20
Ported-by: Richard Yao <ryao@gentoo.org>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #1775
3829 fix for 3740 changed behavior of zfs destroy/hold/release ioctl
Reviewed by: Matt Amdur <matt.amdur@delphix.com>
Reviewed by: Christopher Siden <christopher.siden@delphix.com>
Approved by: Richard Lowe <richlowe@richlowe.net>
References:
https://www.illumos.org/issues/3829illumos/illumos-gate@bb6e70758d
Ported-by: Richard Yao <ryao@gentoo.org>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #1775
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.
3743 zfs needs a refcount audit
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Reviewed by: Eric Schrock <eric.schrock@delphix.com>
Reviewed by: George Wilson <george.wilson@delphix.com>
Approved by: Christopher Siden <christopher.siden@delphix.com>
References:
https://www.illumos.org/issues/3743illumos/illumos-gate@b287be1ba8
Ported-by: Richard Yao <ryao@gentoo.org>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #1775
3742 zfs comments need cleaner, more consistent style
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Reviewed by: George Wilson <george.wilson@delphix.com>
Reviewed by: Eric Schrock <eric.schrock@delphix.com>
Approved by: Christopher Siden <christopher.siden@delphix.com>
References:
https://www.illumos.org/issues/3742illumos/illumos-gate@f717074149
Ported-by: Richard Yao <ryao@gentoo.org>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #1775
Porting notes:
1. The change to zfs_vfsops.c was dropped because it involves
zfs_mount_label_policy, which does not exist in the Linux port.
3741 zfs needs better comments
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Reviewed by: Eric Schrock <eric.schrock@delphix.com>
Approved by: Christopher Siden <christopher.siden@delphix.com>
References:
https://www.illumos.org/issues/3741illumos/illumos-gate@3e30c24aee
Ported-by: Richard Yao <ryao@gentoo.org>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #1775
3699 zfs hold or release of a non-existent snapshot does not output error
3739 cannot set zfs quota or reservation on pool version < 22
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Reviewed by: Eric Shrock <eric.schrock@delphix.com>
Approved by: Dan McDonald <danmcd@nexenta.com>
References:
https://www.illumos.org/issues/3699https://www.illumos.org/issues/3739illumos/illumos-gate@013023d4ed
Ported-by: Richard Yao <ryao@gentoo.org>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #1775
3582 zfs_delay() should support a variable resolution
3584 DTrace sdt probes for ZFS txg states
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Reviewed by: George Wilson <george.wilson@delphix.com>
Reviewed by: Christopher Siden <christopher.siden@delphix.com>
Reviewed by: Dan McDonald <danmcd@nexenta.com>
Reviewed by: Richard Elling <richard.elling@dey-sys.com>
Approved by: Garrett D'Amore <garrett@damore.org>
References:
https://www.illumos.org/issues/3582illumos/illumos-gate@0689f76
Ported by: Ned Bass <bass6@llnl.gov>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #1775
References:
illumos/illumos-gate@44bffe012c
Ported-by: Richard Yao <ryao@gentoo.org>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #1775
References:
illumos/illumos-gate@d39ee142a9
Ported-by: Richard Yao <ryao@gentoo.org>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #1775
Porting notes:
1. This commit was so old that only two lines applied to the modern
code base.
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.
3645 dmu_send_impl: possibilty of pool hold leak
3692 Panic on zfs receive of a recursive deduplicated stream
Reviewed by: Adam Leventhal <ahl@delphix.com>
Reviewed by: Christopher Siden <christopher.siden@delphix.com>
Reviewed by: Dan McDonald <danmcd@nexenta.com>
Approved by: Richard Lowe <richlowe@richlowe.net>
References:
https://www.illumos.org/issues/3645https://www.illumos.org/issues/3692illumos/illumos-gate@de8d9cff56
Ported-by: Richard Yao <ryao@gentoo.org>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #1792
Issue #1775
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
3517 importing pool with autoreplace=on and "hole" vdevs crashes syseventd
Reviewed by: Albert Lee <trisk@nexenta.com>
Reviewed by: Jeffry Molanus <jeffry.molanus@nexenta.com>
Reviewed by: George Wilson <gwilson@zfsmail.com>
Approved by: Christopher Siden <christopher.siden@delphix.com>
References:
https://www.illumos.org/issues/3517illumos/illumos-gate@efb4a871d8
Ported-by: Richard Yao <ryao@gentoo.org>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #1775
3603 panic from bpobj_enqueue_subobj()
3604 zdb should print bpobjs more verbosely
3871 GCC 4.5.3 does not like issue 3604 patch
Reviewed by: Henrik Mattson <henrik.mattson@delphix.com>
Reviewed by: Adam Leventhal <ahl@delphix.com>
Reviewed by: Christopher Siden <christopher.siden@delphix.com>
Reviewed by: George Wilson <george.wilson@delphix.com>
Reviewed by: Garrett D'Amore <garrett@damore.org>
Approved by: Dan McDonald <danmcd@nexenta.com>
References:
https://www.illumos.org/issues/3603https://www.illumos.org/issues/3604https://www.illumos.org/issues/3871illumos/illumos-gate@d04756377d
Ported-by: Richard Yao <ryao@gentoo.org>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #1775
Note that the patch from Illumos issue 3871 is not accepted into Illumos
at the time of this writing. It is something that I wrote when porting
this. Documentation is in the Illumos issue.
3588 provide zfs properties for logical (uncompressed) space
used and referenced
Reviewed by: Adam Leventhal <ahl@delphix.com>
Reviewed by: George Wilson <george.wilson@delphix.com>
Reviewed by: Dan McDonald <danmcd@nexenta.com>
Reviewed by: Richard Elling <richard.elling@dey-sys.com>
Approved by: Richard Lowe <richlowe@richlowe.net>
References:
https://www.illumos.org/issues/3588illumos/illumos-gate@77372cb0f3
Ported-by: Richard Yao <ryao@gentoo.org>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
3578 transferring the freed map to the defer map should be constant time
3579 ztest trips assertion in metaslab_weight()
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Reviewed by: Dan Kimmel <dan.kimmel@delphix.com>
Reviewed by: Adam Leventhal <ahl@delphix.com>
Reviewed by: Christopher Siden <christopher.siden@delphix.com>
Reviewed by: Richard Elling <richard.elling@dey-sys.com>
Approved by: Dan McDonald <danmcd@nexenta.com>
References:
https://www.illumos.org/issues/3578https://www.illumos.org/issues/3579illumos/illumos-gate@9eb57f7f3f
Ported-by: Richard Yao <ryao@gentoo.org>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
3561 arc_meta_limit should be exposed via kstats
3116 zpool reguid may log negative guids to internal SPA history
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Reviewed by: Adam Leventhal <ahl@delphix.com>
Reviewed by: Christopher Siden <christopher.siden@delphix.com>
Reviewed by: Gordon Ross <gordon.ross@nexenta.com>
Approved by: Garrett D'Amore <garrett@damore.org>
References:
https://www.illumos.org/issues/3561https://www.illumos.org/issues/3116illumos/illumos-gate@20128a0826
Ported-by: Richard Yao <ryao@gentoo.org>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Porting Notes:
1. The spa change was accidentally included in the libzfs_core merge.
2. "Add missing arcstats" (1834f2d8b7)
already implemented these kstats a few years ago.
3537 want pool io kstats
Reviewed by: George Wilson <george.wilson@delphix.com>
Reviewed by: Adam Leventhal <ahl@delphix.com>
Reviewed by: Eric Schrock <eric.schrock@delphix.com>
Reviewed by: Sa?o Kiselkov <skiselkov.ml@gmail.com>
Reviewed by: Garrett D'Amore <garrett@damore.org>
Reviewed by: Brendan Gregg <brendan.gregg@joyent.com>
Approved by: Gordon Ross <gwr@nexenta.com>
References:
http://www.illumos.org/issues/3537illumos/illumos-gate@c3a6601
Ported by: Cyril Plisko <cyril.plisko@mountall.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Porting Notes:
1. The patch was restructured to take advantage of the existing
spa statistics infrastructure. To accomplish this the kstat
was moved in to spa->io_stats and the init/destroy code moved
to spa_stats.c.
2. The I/O kstat was simply named <pool> which conflicted with the
pool directory we had already created. Therefore it was renamed
to <pool>/io
3. An update handler was added to allow the kstat to be zeroed.
3522 zfs module should not allow uninitialized variables
Reviewed by: Sebastien Roy <seb@delphix.com>
Reviewed by: Adam Leventhal <ahl@delphix.com>
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Approved by: Garrett D'Amore <garrett@damore.org>
References:
https://www.illumos.org/issues/3522illumos/illumos-gate@d5285cae91
Ported-by: Richard Yao <ryao@gentoo.org>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Porting notes:
1. ZFSOnLinux had already addressed many of these issues because of
its use of -Wall. However, the manner in which they were addressed
differed. The illumos fixes replace the ones previously made in
ZFSOnLinux to reduce code differences.
2. Part of the upstream patch made a small change to arc.c that might
address zfsonlinux/zfs#1334.
3. The initialization of aclsize in zfs_log_create() differs because
vsecp is a NULL pointer on ZFSOnLinux.
4. The changes to zfs_register_callbacks() were dropped because it
has diverged and needs to be resynced.
Modifying the length of a string returned by strdup() is incorrect
because strfree() is allowed to use strlen() to determine which slab
cache was used to do the allocation.
Signed-off-by: Richard Yao <ryao@gentoo.org>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #1775
The resolution of a merge conflict when merging Illumos #3464 caused us
to invert the order couple of function calls in zio_free_sync() versus
what they are in Illumos.
Signed-off-by: Richard Yao <ryao@gentoo.org>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #1775
This was accidentally removed by overzealous commenting.
Signed-off-by: Richard Yao <ryao@gentoo.org>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #1775
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
Attempting to remove an xattr from a file which does not contain
any directory based xattrs would result in the xattr directory
being created. This behavior is non-optimal because it results
in write operations to the pool in addition to the expected error
being returned.
To prevent this the CREATE_XATTR_DIR flag is only passed in
zpl_xattr_set_dir() when setting a non-NULL xattr value. In
addition, zpl_xattr_set() is updated similarly such that it will
return immediately if passed an xattr name which doesn't exist
and a NULL value.
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>
Issue #170
This does the following:
1. It creates a uint8_t type value, which is initialized to DT_DIR on
dot directories and ZFS_DIRENT_TYPE(zap.za_first_integer) otherwise.
This resolves a regression where we return unintialized values as the
directory entry type on dot directories. This was accidentally
introduced by commit 8170d28126.
2. It restructures zfs_readdir() code to use `uint64_t offset` like
Illumos instead of `loff_t *pos`. This resolves a regression where
negative ZAP cursors were treated as if they were dot directories.
3. It restructures the function to more closely match the structure of
zfs_readdir() on Illumos and removes the unused variable outcount, which
was only used on Illumos.
Signed-off-by: Richard Yao <ryao@gentoo.org>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#1750
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>
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
The semantics introduced by the restructured sync task of illumos
3464 require this lock when calling dmu_snapshot_list_next().
The pool is locked/unlocked for each iteration to reduce the
chance of long-running locks.
This was accidentally missed when doing the original port because
ZoL's control directory code is Linux-specific and is in a
different file than in illumos.
Signed-off-by: Richard Yao <ryao@gentoo.org>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#1785
3552 condensing one space map burns 3 seconds of CPU in spa_sync()
thread (fix race condition)
References:
https://www.illumos.org/issues/3552illumos/illumos-gate@03f8c36688
Ported-by: Richard Yao <ryao@gentoo.org>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Porting notes:
This fixes an upstream regression that was introduced in commit
zfsonlinux/zfs@e51be06697, which
ported the Illumos 3552 changes. This fix was added to upstream
rather quickly, but at the time of the port, no one spotted it and
the race was rare enough that it passed our regression tests. I
discovered this when comparing our metaslab.c to the illumos
metaslab.c.
Without this change it is possible for metaslab_group_alloc() to
consume a large amount of cpu time. Since this occurs under a
mutex in a rcu critical section the kernel will log this to the
console as a self-detected cpu stall as follows:
INFO: rcu_sched self-detected stall on CPU { 0}
(t=60000 jiffies g=11431890 c=11431889 q=18271)
Closes#1687Closes#1720Closes#1731Closes#1747
These are needed by consumers (i.e. Lustre) who wish to use the
dsl_prop_register() interface to register callbacks when pool
properties of interest change. This interface requires that the
DSL pool configuration lock is held when called.
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#1762
When building the spl with --enable-debug-kmem-tracking a memory
leak is detected in log_internal(). This happens to be a false
positive because the memory was freed using strfree() instead of
kmem_free(). All kmem_alloc()'s must be released with kmem_free()
to ensure correct accounting.
SPL: kmem leaked 135/5641311 bytes
address size data func:line
ffff8800cba7cd80 135 ZZZZZZZZZZZZZZZZ log_internal:456
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
The recent sync task restructuring in 13fe019 introduced several
new symbols which should be exported for use by consumers such
as Lustre.
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Some ZFS errors such as certain snapshot failures can occur in
the sync task context. Because they may require additional memory
allocations, the initial nvlist must be allocated with KM_PUSHPAGE.
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #1746
Issue #1737
A handful of allocations now occur in the sync path and need
to use KM_PUSHPAGE. These were introduced by commit 13fe019.
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #1746
Issue #1737
The spa_deadman() and spa_sync() functions can both be run in the
spa_sync context and therefore should use TQ_PUSHPAGE instead of
TQ_SLEEP.
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#1734Closes#1749
Locking mutex &vq->vq_lock in vdev_mirror_pending is unneeded:
* no data is modified
* only vq_pending_tree is read
* in case garbage is returned (eg. vq_pending_tree being updated
while the read is made) the worst case would be that a single
read could be queued on a mirror side which more busy than thought
The benefit of this change is streamlining of the code path since
it is taken for *every* mirror member on *every* read.
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#1739
dataset_remove_clones_key does recursion, so if the recursion goes
deep it can overrun the linux kernel stack size of 8KB. I have seen
this happen in the actual deployment, and subsequently confirmed it by
running a test workload on a custom-built kernel that uses 32KB stack.
See the following stack trace as an example of the case where it would
have run over the 8KB stack kernel:
Depth Size Location (42 entries)
----- ---- --------
0) 11192 72 __kmalloc+0x2e/0x240
1) 11120 144 kmem_alloc_debug+0x20e/0x500
2) 10976 72 dbuf_hold_impl+0x4a/0xa0
3) 10904 120 dbuf_prefetch+0xd3/0x280
4) 10784 80 dmu_zfetch_dofetch.isra.5+0x10f/0x180
5) 10704 240 dmu_zfetch+0x5f7/0x10e0
6) 10464 168 dbuf_read+0x71e/0x8f0
7) 10296 104 dnode_hold_impl+0x1ee/0x620
8) 10192 16 dnode_hold+0x19/0x20
9) 10176 88 dmu_buf_hold+0x42/0x1b0
10) 10088 144 zap_lockdir+0x48/0x730
11) 9944 128 zap_cursor_retrieve+0x1c4/0x2f0
12) 9816 392 dsl_dataset_remove_clones_key.isra.14+0xab/0x190
13) 9424 392 dsl_dataset_remove_clones_key.isra.14+0x10c/0x190
14) 9032 392 dsl_dataset_remove_clones_key.isra.14+0x10c/0x190
15) 8640 392 dsl_dataset_remove_clones_key.isra.14+0x10c/0x190
16) 8248 392 dsl_dataset_remove_clones_key.isra.14+0x10c/0x190
17) 7856 392 dsl_dataset_remove_clones_key.isra.14+0x10c/0x190
18) 7464 392 dsl_dataset_remove_clones_key.isra.14+0x10c/0x190
19) 7072 392 dsl_dataset_remove_clones_key.isra.14+0x10c/0x190
20) 6680 392 dsl_dataset_remove_clones_key.isra.14+0x10c/0x190
21) 6288 392 dsl_dataset_remove_clones_key.isra.14+0x10c/0x190
22) 5896 392 dsl_dataset_remove_clones_key.isra.14+0x10c/0x190
23) 5504 392 dsl_dataset_remove_clones_key.isra.14+0x10c/0x190
24) 5112 392 dsl_dataset_remove_clones_key.isra.14+0x10c/0x190
25) 4720 392 dsl_dataset_remove_clones_key.isra.14+0x10c/0x190
26) 4328 392 dsl_dataset_remove_clones_key.isra.14+0x10c/0x190
27) 3936 392 dsl_dataset_remove_clones_key.isra.14+0x10c/0x190
28) 3544 392 dsl_dataset_remove_clones_key.isra.14+0x10c/0x190
29) 3152 392 dsl_dataset_remove_clones_key.isra.14+0x10c/0x190
30) 2760 392 dsl_dataset_remove_clones_key.isra.14+0x10c/0x190
31) 2368 392 dsl_dataset_remove_clones_key.isra.14+0x10c/0x190
32) 1976 392 dsl_dataset_remove_clones_key.isra.14+0x10c/0x190
33) 1584 392 dsl_dataset_remove_clones_key.isra.14+0x10c/0x190
34) 1192 232 dsl_dataset_destroy_sync+0x311/0xf60
35) 960 72 dsl_sync_task_group_sync+0x12f/0x230
36) 888 168 dsl_pool_sync+0x48b/0x5c0
37) 720 184 spa_sync+0x417/0xb00
38) 536 184 txg_sync_thread+0x325/0x5b0
39) 352 48 thread_generic_wrapper+0x7a/0x90
40) 304 128 kthread+0xc0/0xd0
41) 176 176 ret_from_fork+0x7c/0xb0
This change reduces the stack usage in dsl_dataset_remove_clones_key
by allocating structures in heap, not in stack. This is not a fundamental
fix, as one can create an arbitrary large data set that runs over any
fixed size stack, but this will make the problem far less likely.
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Kohsuke Kawaguchi <kk@kohsuke.org>
Closes#1726
The zpl_mknod() function was incorrectly negating its return value.
This doesn't cause any problems in the success case, but it does
prevent us from returning the correct error code for a failure.
The implementation of this function is now consistent with all
the other zpl_* functions.
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#1717
When compiling on an ARM device using gcc 4.7.3 several variables
in the zfs_obj_to_path_impl() function were flagged as uninitialized.
To resolve the warnings explicitly initialize them to zero.
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#1716
After the restructuring in 13fe019 The 'zfs rename' command will
result in a KM_SLEEP being called in the sync context. This may
deadlock due to reclaim so it was changed to KM_PUSHPAGE.
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#1711
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.
There is currently a subtle bug in the SA implementation which
can crop up which prevents us from safely using multiple variable
length SAs in one object.
Fortunately, the only existing use case for this are symlinks with
SA based xattrs. Therefore, until the root cause in the SA code
can be identified and fixed we prevent adding SA xattrs to symlinks.
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #1468
This reverts commit fadd0c4da1 which
introduced a regression in honoring the meta limit.
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Close#1660
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
Because we need to be more frugal about our stack usage under
Linux. The __zio_execute() function was modified to re-dispatch
zios to a ZIO_TASKQ_ISSUE thread when we're in a context which
is known to be stack heavy. Those two contexts are the sync
thread and what ever thread is performing spa initialization.
Unfortunately, this change introduced an unlikely bug which can
result in a zio being re-dispatched indefinitely and never being
executed. If during spa initialization we handle a zio with
ZIO_PRIORITY_NOW it will be moved to the high priority queue.
When __zio_execute() is called again for the zio it will mis-
interpret the context and re-dispatch it again. The system
will get stuck spinning re-dispatching the zio and making no
forward progress.
To fix this rare issue __zio_execute() has been updated not
to re-dispatch zios on either the ZIO_TASKQ_ISSUE or
ZIO_TASKQ_ISSUE_HIGH task queues.
In practice this issue was rarely reported and can usually
be fixed by rebooting the system and importing the pool again.
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#1455
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
When CONFIG_UIDGID_STRICT_TYPE_CHECKS is enabled uid_t/git_t are
replaced by kuid_t/kgid_t, which are structures instead of integral
types. This causes any code that uses an integral type to fail to build.
The User Namespace functionality introduced in Linux 3.8 requires
CONFIG_UIDGID_STRICT_TYPE_CHECKS, so we could not build against any
kernel that supported it.
We resolve this by converting between the new kuid_t/kgid_t structures
and the original uid_t/gid_t types.
Signed-off-by: Richard Yao <ryao@gentoo.org>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#1589
When the meta limit is exceeded the ARC evicts some meta data
buffers from the mfu+mru lists. Unfortunately, for meta data
heavy workloads it's possible for these buffers to accumulate
on the ghost lists if arc_c doesn't exceed arc_size.
To handle this case arc_adjust_meta() has been entended to
explicitly evict meta data buffers from the ghost lists in
proportion to what was evicted from the mfu+mru lists.
If this is insufficient we request that the VFS release
some inodes and dentries. This will result in the release
of some dnodes which are counted as 'other' metadata.
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
The default behavior of arc_evict_ghost() is to start by evicting
data buffers. Then only if the requested number of bytes to evict
cannot be satisfied by data buffers move on to meta data buffers.
This is ideal for honoring arc_c since it's preferable to keep the
meta data cached. However, if we're trying to free memory from the
arc to honor the meta limit it's a problem because we will need to
discard all the data to get to the meta data.
To avoid this issue the arc_evict_ghost() is now passed a fourth
argumented describing which buffer type to start with. The
arc_evict() function already behaves exactly like this for a
same reason so this is consistent with the existing code.
All existing callers have been updated to pass ARC_BUFC_DATA so
this patch introduces no functional change. New callers may
pass ARC_BUFC_METADATA to skip immediately to evicting meta
data leaving the normal data untouched.
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
3137 L2ARC compression
Reviewed by: George Wilson <george.wilson@delphix.com>
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Approved by: Dan McDonald <danmcd@nexenta.com>
References:
illumos/illumos-gate@aad02571bchttps://www.illumos.org/issues/3137http://wiki.illumos.org/display/illumos/L2ARC+Compression
Notes for Linux port:
A l2arc_nocompress module option was added to prevent the
compression of l2arc buffers regardless of how a dataset's
compression property is set. This allows the legacy behavior
to be preserved.
Ported by: James H <james@kagisoft.co.uk>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#1379
This is analogous to SPL commit zfsonlinux/spl@b9b3715. While
we don't have clear evidence of systems getting caught here
indefinately like in the SPL this ensures that it will never
happen.
Signed-off-by: Richard Yao <ryao@gentoo.org>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#1579
zfs_readdir() is used by getdents(), which provides a list of all files
in directory, their types and an offset that be used by llseek() to seek
to the next directory entry.
On Solaris, the first two directory entries "." and ".." respectively
have offsets 1 and 2 on ZFS while the other files have rather large
numbers. Currently, ZFSOnLinux is giving "." offset 0 and all other
entries large numbers. The first entry's next entry offset points to
itself, which causes software that uses llseek() in conjunction with
getdents() for filesystem navigation to enter an infinite loop. The
offsets used for each directory entry are filesystem specific on all
platforms, so we can fix this by adopting the Solaris behavior.
Also, we currently report each directory entry as having type 0 (???).
This is not wrong, but we can do better. getdents() on Solaris does not
appear to provide this information, but it does on Linux and Mac OS X
do. ZFS provides easy access to type information in zfs_readdir(), so
this patch provides this as well.
Reported-by: Andrey <andrey@kudinov.su>
Signed-off-by: Richard Yao <ryao@gentoo.org>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#1624
3639 zpool.cache should skip over readonly pools
Reviewed by: Eric Schrock <eric.schrock@delphix.com>
Reviewed by: Adam Leventhal <ahl@delphix.com>
Reviewed by: Basil Crow <basil.crow@delphix.com>
Approved by: Gordon Ross <gwr@nexenta.com>
References:
illumos/illumos-gate@fb02ae0252https://www.illumos.org/issues/3639
Normally we don't list pools that are imported read-only in the cache
file, however you can accidentally get one into the cache file by
importing and exporting a read-write pool while a read-only pool is
imported:
$ zpool import -o readonly test1
$ zpool import test2
$ zpool export test2
$ zdb -C
This is a problem because if the machine reboots we import all pools in
the cache file as read-write.
Ported-by: Richard Yao <ryao@gentoo.org>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
When the property atime=on is set operations which only access
and inode do cause an atime update. However, it turns out that
dirty inodes with updated atimes are only written to disk when
the inodes get evicted from the cache. Somewhat surprisingly
the source suggests that this isn't a ZoL specific issue.
This behavior may in part explain why zfs's reclaim logic has
been observed to be slow. When reclaiming inodes its likely
that they have a dirty atime which will force a write to disk.
Obviously we don't want to force a write to disk for every
atime update, these needs to be batched. The right way to
do this is to fully implement the .dirty_inode and .write_inode
callbacks. However, to do that right requires proper unification
of some fields in the znode/inode. Then we could just mark the
inode dirty and leave it to the VFS to call .write_inode
periodically.
Until that work gets done we have to settle for some middle
ground. The simplest and safest thing we can do for now is
to write the dirty inode on last close. This should prevent
the majority of inodes in the cache from having dirty atimes
and not drastically increase the number of writes.
Some rudimentally testing to show how long it takes to drop
500,000 inodes from the cache shows promising results. This
is as expected because we're no longer do lots of IO as part
of the eviction, it was done earlier during the close.
w/out patch: ~30s to drop 500,000 inodes with drop_caches.
with patch: ~3s to drop 500,000 inodes with drop_caches.
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
The dmu_prefetch, dmu_free_long_range, dmu_free_object,
dmu_prealloc, dmu_write_policy, and dmu_sync symbols have
been exported so they may be used by other modules.
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
dmu_tx_hold_object_impl can return NULL on error. Check for this
condition prior to dereferencing pointer. This can only occur if
the passed object was invalid or unallocated.
Signed-off-by: Nathaniel Clark <Nathaniel.Clark@misrule.us>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#1610
The code involving b_thawed appears to be dead, so lets discard it.
Signed-off-by: Richard Yao <ryao@gentoo.org>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #1614
These functions are used in neither Illumos nor ZFSOnLinux. They appear
to have been replaced by arc_buf_alloc()/arc_buf_free(), so lets remove
them.
Signed-off-by: Richard Yao <ryao@gentoo.org>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #1614
We declare zio_alloc_arena using extern, but it does not appear to exist
anywhere in the code. This permits undefined behavior, so lets remove
it.
Signed-off-by: Richard Yao <ryao@gentoo.org>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #1614
The l2arc module options can be made safely writable. This allows
the options to be changed without unloading/loading the modules.
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
These days modern SSDs can efficiently service concurrent reads
and writes. When this flag was added that wasn't really the
case for a variety of SSD controllers. But now we can set the
default value to take advantage of this parallelism and only
disable this as needed for specific troublesome hardware.
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Based on the comments in arc.c we know that buffers can exist both
in arc and l2arc, under this circumstance both arc_buf_hdr_t and
l2arc_buf_hdr_t will be allocated. However the current logic only
cares for memory that l2arc_buf_hdr takes up when the buffer's
state transfers from or to arc_l2c_only. This will cause obvious
deviations for illumos's zfs version since the sizeof(l2arc_buf_hdr)
is larger than ZOL's. We can implement the calcuation in the
following simple way:
1. When allocate a l2arc_buf_hdr_t we add its memory consumption
instantly and subtract it when we free or evict the l2arc buf.
2. According to l2arc_hdr_stat_add and l2arc_hdr_stat_remove, if
the buffer only stays in l2arc we should also add the memory
its arc_buf_hdr_t consumes, so we only need to add HDR_SIZE to
arcstat_l2_hdr_size since we already concerned with L2HDR_SIZE
in step 1 and the same for transfering arc bufs from l2arc only
state.
The testbox has 2 4-core Intel Xeon CPUs(2.13GHz), with 16GB memory
and tests were set upped in the following way:
1. Fdisked a SATA disk into two partitions, one partition for zpool
storage and the other one was used as the cache device.
2. Generated some files occupying 14GB altogether in the zpool
prepared in step 1 using iozone.
3. Read them all using md5sum and watched the l2arc related statistics
in /proc/spl/kstat/zfs/arcstats. After the reading ended the
l2_hdr_size and l2_size were shown like this:
l2_size 4 4403780608
l2_hdr_size 4 0
which was weird.
4. After applying this patch and reran step 1-3, the results were
as following:
l2_size 4 4306443264
l2_hdr_size 4 535600
these numbers made sense, on 64-bit systems the
sizeof(l2arc_buf_hdr_t) is 16 bytes. Assue all blocks cached by
l2arc are 128KB, so 535600/16*128*1024=4387635200, since not all
blocks are equal-sized, the theoretical result will be a little
bigger, as we can see.
Since I'm familiar with systemtap instrumentation tool I used it to
examine what had happened. The script looked like this:
probe module("zfs").function("arc_chage_state")
{
if ($new_state == $arc_l2_only)
printf("change arc buf to arc_l2_only\n")
}
It will print out some information each time we call funciton
arc_chage_state if the argument new_state is arc_l2_only. I
gathered the trace logs and found that none of the arc bufs ran
into arc state arc_l2_only when the tests was running, this was
the reason why l2_hdr_size in step 3 was 0. The arc bufs fell into
arc_l2_only when the pool or the filesystem was offlined.
Signed-off-by: Ying Zhu <casualfisher@gmail.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
The iterate_supers_type() function which was introduced in the
3.0 kernel was supposed to provide a safe way to call an arbitrary
function on all super blocks of a specific type. Unfortunately,
because a list_head was used a bug was introduced which made it
possible for iterate_supers_type() to get stuck spinning on a
super block which was just deactivated.
This can occur because when the list head is removed from the
fs_supers list it is reinitialized to point to itself. If the
iterate_supers_type() function happened to be processing the
removed list_head it will get stuck spinning on that list_head.
The bug was fixed in the 3.3 kernel by converting the list_head
to an hlist_node. However, to resolve the issue for existing
3.0 - 3.2 kernels we detect when a list_head is used. Then to
prevent the spinning from occurring the .next pointer is set to
the fs_supers list_head which ensures the iterate_supers_type()
function will always terminate.
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#1045Closes#861Closes#790
During mount a filesystem dataset would have the MS_RDONLY bit
incorrectly cleared even if the entire pool was read-only.
There is existing to code to handle this case but it was being run
before the property callbacks were registered. To resolve the
issue we move this read-only code after the callback registration.
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#1338
It is possible for an automounted snapshot which is expiring to
deadlock with a manual unmount of the snapshot. This can occur
because taskq_cancel_id() will block if the task is currently
executing until it completes. But it will never complete because
zfsctl_unmount_snapshot() is holding the zsb->z_ctldir_lock which
zfsctl_expire_snapshot() must acquire.
---------------------- z_unmount/0:2153 ---------------------
mutex_lock <blocking on zsb->z_ctldir_lock>
zfsctl_unmount_snapshot
zfsctl_expire_snapshot
taskq_thread
------------------------- zfs:10690 -------------------------
taskq_wait_id <waiting for z_unmount to exit>
taskq_cancel_id
__zfsctl_unmount_snapshot
zfsctl_unmount_snapshot <takes zsb->z_ctldir_lock>
zfs_unmount_snap
zfs_ioc_destroy_snaps_nvl
zfsdev_ioctl
do_vfs_ioctl
We resolve the deadlock by dropping the zsb->z_ctldir_lock before
calling __zfsctl_unmount_snapshot(). The lock is only there to
prevent concurrent modification to the zsb->z_ctldir_snaps AVL
tree. Moreover, we're careful to remove the zfs_snapentry_t from
the AVL tree before dropping the lock which ensures no other tasks
can find it. On failure it's added back to the tree.
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Chris Dunlap <cdunlap@llnl.gov>
Closes#1527
The read bandwidth of an N-way mirror can by increased by 50%,
and the IOPs by 10%, by more carefully selecting the preferred
leaf vdev.
The existing algorthm selects a perferred leaf vdev based on
offset of the zio request modulo the number of members in the
mirror. It assumes the drives are of equal performance and
that spreading the requests randomly over both drives will be
sufficient to saturate them. In practice this results in the
leaf vdevs being under utilized.
Utilization can be improved by preferentially selecting the leaf
vdev with the least pending IO. This prevents leaf vdevs from
being starved and compensates for performance differences between
disks in the mirror. Faster vdevs will be sent more work and
the mirror performance will not be limitted by the slowest drive.
In the common case where all the pending queues are full and there
is no single least busy leaf vdev a batching stratagy is employed.
Of the N least busy vdevs one is selected with equal probability
to be the preferred vdev for T microseconds. Compared to randomly
selecting a vdev to break the tie batching the requests greatly
improves the odds of merging the requests in the Linux elevator.
The testing results show a significant performance improvement
for all four workloads tested. The workloads were generated
using the fio benchmark and are as follows.
1) 1MB sequential reads from 16 threads to 16 files (MB/s).
2) 4KB sequential reads from 16 threads to 16 files (MB/s).
3) 1MB random reads from 16 threads to 16 files (IOP/s).
4) 4KB random reads from 16 threads to 16 files (IOP/s).
| Pristine | With 1461 |
| Sequential Random | Sequential Random |
| 1MB 4KB 1MB 4KB | 1MB 4KB 1MB 4KB |
| MB/s MB/s IO/s IO/s | MB/s MB/s IO/s IO/s |
---------------+-----------------------+------------------------+
2 Striped | 226 243 11 304 | 222 255 11 299 |
2 2-Way Mirror | 302 324 16 534 | 433 448 23 571 |
2 3-Way Mirror | 429 458 24 714 | 648 648 41 808 |
2 4-Way Mirror | 562 601 36 849 | 816 828 82 926 |
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#1461
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
a new dmu_tx_assign_histogram-$POOLNAME file. The information contained
in this histogram is the frequency dmu_tx_assign took to complete given
an interval range. For example, given the below histogram file:
$ cat /proc/spl/kstat/zfs/dmu_tx_assign_histogram-tank
12 1 0x01 32 1536 19792068076691 20516481514522
name type data
1 us 4 859
2 us 4 252
4 us 4 171
8 us 4 2
16 us 4 0
32 us 4 2
64 us 4 0
128 us 4 0
256 us 4 0
512 us 4 0
1024 us 4 0
2048 us 4 0
4096 us 4 0
8192 us 4 0
16384 us 4 0
32768 us 4 1
65536 us 4 1
131072 us 4 1
262144 us 4 4
524288 us 4 0
1048576 us 4 0
2097152 us 4 0
4194304 us 4 0
8388608 us 4 0
16777216 us 4 0
33554432 us 4 0
67108864 us 4 0
134217728 us 4 0
268435456 us 4 0
536870912 us 4 0
1073741824 us 4 0
2147483648 us 4 0
one can see most calls to dmu_tx_assign completed in 32us or less, but a
few outliers did not. Specifically, 4 of the calls took between 262144us
and 131072us. This information is difficult, if not impossible, to gather
without this change.
Signed-off-by: Prakash Surya <surya1@llnl.gov>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#1584
In the event that a pool gets suspended log this information to
the console. This is critical information and we want to make
sure it gets logged.
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#1555
To avoid a potential deadlock when using a zvol as a swap
device prevent vdev_disk_io_flush() from performing IO during
the bio_alloc().
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#1508
When we remove references of arc bufs in the arc_anon state we
needn't take its header's hash_lock, so postpone it to where we
really need it to avoid unnecessary invocations of function buf_hash.
Signed-off-by: Ying Zhu <casualfisher@gmail.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#1557
