Reviewed by: George Wilson <george.wilson@delphix.com>
Reviewed by: John Kennedy <john.kennedy@delphix.com>
Approved by: Garrett D'Amore <garrett@damore.org>
Author: Matt Ahrens <Matt.Ahrens@delphix.com>
With compressed ARC (6950) we use up to 25% of our CPU to decompress indirect
blocks, under a workload of random cached reads. To reduce this decompression
cost, we would like to increase the size of the dbuf cache so that more
indirect blocks can be stored uncompressed.
If we are caching entire large files of recordsize=8K, the indirect blocks
use 1/64th as much memory as the data blocks (assuming they have the same
compression ratio). We suggest making the dbuf cache be 1/32nd of all memory,
so that in this scenario we should be able to keep all the indirect blocks
decompressed in the dbuf cache. (We want it to be more than the 1/64th that
the indirect blocks would use because we need to cache other stuff in the
dbuf cache as well.)
In real world workloads, this won't help as dramatically as the example
above, but we think it's still worth it because the risk of decreasing
performance is low. The potential negative performance impact is that we
will be slightly reducing the size of the ARC (by ~3%).
Reviewed by: Dan Kimmel <dan.kimmel@delphix.com>
Reviewed by: Prashanth Sreenivasa <pks@delphix.com>
Reviewed by: Paul Dagnelie <pcd@delphix.com>
Reviewed by: Sanjay Nadkarni <sanjay.nadkarni@nexenta.com>
Reviewed by: Allan Jude <allanjude@freebsd.org>
Reviewed by: Igor Kozhukhov <igor@dilos.org>
Approved by: Garrett D'Amore <garrett@damore.org>
Author: George Wilson <george.wilson@delphix.com>
arc_loan_compressed_buf() increments arc_loaned_bytes by psize unconditionally
In the case of zfs_compressed_arc_enabled=0, when the buf is returned via
arc_return_buf(), if ARC_BUF_COMPRESSED(buf) is false, then arc_loaned_bytes
is decremented by lsize, not psize.
Switch to using arc_buf_size(buf), instead of psize, which will return
psize or lsize, depending on the result of ARC_BUF_COMPRESSED(buf).
Reviewed by: Matt Ahrens <matt@delphix.com>
Reviewed by: George Wilson <george.wilson@delphix.com>
Approved by: Garrett D'Amore <garrett@damore.org>
Author: Allan Jude <allanjude@freebsd.org>
We want to be able to pass various settings during import/open of a pool,
which are not only related to rewind. Instead of adding a new policy and
duplicate a bunch of code, we should just rename rewind_policy to a more
generic term like load_policy.
For instance, we'd like to set spa->spa_import_flags from the nvlist,
rather from a flags parameter passed to spa_import as in some cases we want
those flags not only for the import case, but also for the open case. One
such flag could be ZFS_IMPORT_MISSING_LOG (as used in zdb) which would
allow zfs to open a pool when logs are missing.
Reviewed by: Matt Ahrens <matt@delphix.com>
Reviewed by: George Wilson <george.wilson@delphix.com>
Approved by: Robert Mustacchi <rm@joyent.com>
Author: Pavel Zakharov <pavel.zakharov@delphix.com>
Reviewed by: George Wilson <george.wilson@delphix.com>
Reviewed by: Prakash Surya <prakash.surya@delphix.com>
Reviewed by: Matt Ahrens <matt@delphix.com>
Approved by: Robert Mustacchi <rm@joyent.com>
Author: Pavel Zakharov <pavel.zakharov@delphix.com>
ztest failed with uncorrectable IO error despite having the fix for #7163.
Both sides of the mirror have CANT_OPEN_BAD_LABEL, which also distinguishes
it from that issue.
Definitely seems like a racing condition between the vdev_validate and spa_sync:
1. Thread A (spa_sync): vdev label is updated to latest txg
2. Thread B (vdev_validate): vdev label's txg is compared to spa_last_synced_txg and is ahead.
3. Thread A (spa_sync): spa_last_synced_txg is updated to latest txg.
Solution: do not check txg in vdev_validate unless config lock is held.
Reviewed by: George Wilson <george.wilson@delphix.com>
Reviewed by: Matt Ahrens <matthew.ahrens@delphix.com>
Approved by: Robert Mustacchi <rm@joyent.com>
Author: Pavel Zakharov <pavel.zakharov@delphix.com>
The idea of Storage Pool Checkpoint (aka zpool checkpoint) deals with
exactly that. It can be thought of as a “pool-wide snapshot” (or a
variation of extreme rewind that doesn’t corrupt your data). It remembers
the entire state of the pool at the point that it was taken and the user
can revert back to it later or discard it. Its generic use case is an
administrator that is about to perform a set of destructive actions to ZFS
as part of a critical procedure. She takes a checkpoint of the pool before
performing the actions, then rewinds back to it if one of them fails or puts
the pool into an unexpected state. Otherwise, she discards it. With the
assumption that no one else is making modifications to ZFS, she basically
wraps all these actions into a “high-level transaction”.
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Reviewed by: John Kennedy <john.kennedy@delphix.com>
Reviewed by: Dan Kimmel <dan.kimmel@delphix.com>
Approved by: Richard Lowe <richlowe@richlowe.net>
Author: Serapheim Dimitropoulos <serapheim.dimitro@delphix.com>
Reviewed by: C Fraire <cfraire@me.com>
Reviewed by: Andy Fiddaman <omnios@citrus-it.co.uk>
Approved by: Joshua M. Clulow <josh@sysmgr.org>
Author: Toomas Soome <tsoome@me.com>
Alexander Motin [Fri, 23 Mar 2018 00:20:42 +0000 (00:20 +0000)]
8484 Implement aggregate sum and use for arc counters
In pursuit of improving performance on multi-core systems, we should
implements fanned out counters and use them to improve the performance of
some of the arc statistics. These stats are updated extremely frequently,
and can consume a significant amount of CPU time.
Reviewed by: Pavel Zakharov <pavel.zakharov@delphix.com>
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Approved by: Dan McDonald <danmcd@joyent.com>
Author: Paul Dagnelie <pcd@delphix.com>
https://www.illumos.org/issues/9164
This issue has been reported by Alan Somers as
https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=225877
dmu_objset_refresh_ownership() first disowns a dataset (and releases
it) and then owns it again. There is an assert that the new dataset
object is the same as the old dataset object. When running ZFS Test
Suite on FreeBSD we see this panic from zpool_upgrade_007_pos test:
panic: solaris assert: newds == os->os_dsl_dataset (0xfffff80045f4c000
== 0xfffff80021ab4800)
I see that the old dataset has dsl_dataset_evict_async() pending in
ds_dbu.dbu_tqent and its ds_dbuf is NULL.
Reviewed by: Matt Ahrens <mahrens@delphix.com>
Reviewed by: Don Brady <don.brady@delphix.com>
Approved by: Richard Lowe <richlowe@richlowe.net>
Author: Andriy Gapon <avg@FreeBSD.org>
https://www.illumos.org/issues/8984
Consider a directory configured as:
drwx-ws---+ 2 henson cpp 3 Jan 23 12:35 dropbox/
user:henson:rwxpdDaARWcC--:f-i----:allow
owner@:--------------:f-i----:allow
group@:--------------:f-i----:allow
everyone@:--------------:f-i----:allow
owner@:rwxpdDaARWcC--:-di----:allow
group:cpp:-wx-----------:-------:allow
owner@:rwxpdDaARWcC--:-------:allow
A new file created in this directory ends up looking like:
rw-r--r-+ 1 astudent cpp 0 Jan 23 12:39 testfile
user:henson:rw-pdDaARWcC--:------I:allow
owner@:--------------:------I:allow
group@:--------------:------I:allow
everyone@:--------------:------I:allow
owner@:rw-p--aARWcCos:-------:allow
group@:r-----a-R-c--s:-------:allow
everyone@:r-----a-R-c--s:-------:allow
with extraneous group@ and everyone@ entries allowing read access that
shouldn't exist.
Per Albert Lee on the zfs mailing list:
"aclinherit=passthrough/passthrough-x should still
ignore the requested mode when an inheritable ACE for owner@ group@,
or everyone@ is present in the parent directory.
It appears there was an oversight in my fix for
https://www.illumos.org/issues/6764 which made calling zfs_acl_chmod
from zfs_acl_inherit unconditional. I think the parent ACL check for
aclinherit=passthrough needs to be reintroduced in zfs_acl_inherit."
We have a large number of faculty who use dropbox directories like the example
to have students submit projects. All of these directories are now allowing
Reviewed by: Sam Zaydel <szaydel@racktopsystems.com>
Reviewed by: Paul B. Henson <henson@acm.org>
Reviewed by: Prakash Surya <prakash.surya@delphix.com>
Approved by: Matthew Ahrens <mahrens@delphix.com>
Author: Dominik Hassler <hadfl@omniosce.org>
"zfs send -t <token>" for an incremental send should be able to resume
successfully when sending to the same pool: a subtle issue in
zfs_iter_children() doesn't currently allow this.
Because resuming from a token requires "guid" -> "dataset" mapping
(guid_to_name()), we have to walk the whole hierarchy to find the right
snapshots to send.
When resuming an incremental send both source and destination live in the
same pool and have the same guid: this is where zfs_iter_children() gets
confused and picks up the wrong snapshot, so we end up trying to send an
incremental "destination@snap1 -> source@snap2" stream instead of
"source@snap1 -> source@snap2": this fails with an "Invalid cross-device
link" (EXDEV) error.
Reviewed by: Paul Dagnelie <pcd@delphix.com>
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Approved by: Hans Rosenfeld <rosenfeld@grumpf.hope-2000.org>
Author: loli10K <ezomori.nozomu@gmail.com>
A scenario came up where a callback executed by vdev_indirect_remap() on a vdev, calls
vdev_indirect_remap() on the same vdev and tries to reacquire vdev_indirect_rwlock that
was already acquired from the first call to vdev_indirect_remap(). The specific scenario,
is that we want to remap a block pointer that is snapshoted but its dataset's remap_deadlist
is not cached. So in order to add it we issue a read through a vdev_indirect_remap() on the
same vdev, which brings up the aforementioned issue.
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Reviewed by: George Wilson <george.wilson@delphix.com>
Approved by: Hans Rosenfeld <rosenfeld@grumpf.hope-2000.org>
Author: Serapheim Dimitropoulos <serapheim.dimitro@delphix.com>
The timeline of the race condition is the following:
[1] Thread A is about to finish condesing the first vdev in spa_condense_indirect_thread(),
so it calls the spa_condense_indirect_complete_sync() sync task which sets the
spa_condensing_indirect field to NULL. Waiting for the sync task to finish, thread A
sleeps until the txg is done. When this happens, thread A will acquire spa_async_lock
and set spa_condense_thread to NULL.
[2] While thread A waits for the txg to finish, thread B which is running spa_sync() checks
whether it should condense the second vdev in vdev_indirect_should_condense() by checking
the spa_condensing_indirect field which was set to NULL by spa_condense_indirect_thread()
from thread A. So it goes on and tries to spawn a new condensing thread in
spa_condense_indirect_start_sync() and the aforementioned assertions fails because thread A
has not set spa_condense_thread to NULL (which is basically the last thing it does before
returning).
The main issue here is that we rely on both spa_condensing_indirect and spa_condense_thread to
signify whether a condensing thread is running. Ideally we would only use one throughout the
codebase. In addition, for managing spa_condense_thread we currently use spa_async_lock which
basically tights condensing to scrubing when it comes to pausing and resuming those actions
during spa export.
Reviewed by: Matt Ahrens <mahrens@delphix.com>
Reviewed by: Pavel Zakharov <pavel.zakharov@delphix.com>
Approved by: Hans Rosenfeld <rosenfeld@grumpf.hope-2000.org>
Author: Serapheim Dimitropoulos <serapheim@delphix.com>
Some work has been done lately to improve the debugability of the ZFS pool
load (and import) process. This includes:
https://www.illumos.org/issues/7638: Refactor spa_load_impl into several functions
https://www.illumos.org/issues/8961: SPA load/import should tell us why it failed
https://www.illumos.org/issues/7277: zdb should be able to print zfs_dbgmsg's
To iterate on top of that, there's a few changes that were made to make the
import process more resilient and crash free. One of the first tasks during the
pool load process is to parse a config provided from userland that describes
what devices the pool is composed of. A vdev tree is generated from that config,
and then all the vdevs are opened.
The Meta Object Set (MOS) of the pool is accessed, and several metadata objects
that are necessary to load the pool are read. The exact configuration of the
pool is also stored inside the MOS. Since the configuration provided from
userland is external and might not accurately describe the vdev tree
of the pool at the txg that is being loaded, it cannot be relied upon to safely
operate the pool. For that reason, the configuration in the MOS is read early
on. In the past, the two configurations were compared together and if there was
a mismatch then the load process was aborted and an error was returned.
The latter was a good way to ensure a pool does not get corrupted, however it
made the pool load process needlessly fragile in cases where the vdev
configuration changed or the userland configuration was outdated. Since the MOS
is stored in 3 copies, the configuration provided by userland doesn't have to be
perfect in order to read its contents. Hence, a new approach has been adopted:
The pool is first opened with the untrusted userland configuration just so that
the real configuration can be read from the MOS. The trusted MOS configuration
is then used to generate a new vdev tree and the pool is re-opened.
When the pool is opened with an untrusted configuration, writes are disabled
to avoid accidentally damaging it. During reads, some sanity checks are
performed on block pointers to see if each DVA points to a known vdev;
when the configuration is untrusted, instead of panicking the system if those
checks fail we simply avoid issuing reads to the invalid DVAs.
This new two-step pool load process now allows rewinding pools accross
vdev tree changes such as device replacement, addition, etc. Loading a pool
from an external config file in a clustering environment also becomes much
safer now since the pool will import even if the config is outdated and didn't,
for instance, register a recent device addition.
With this code in place, it became relatively easy to implement a
long-sought-after feature: the ability to import a pool with missing top level
(i.e. non-redundant) devices. Note that since this almost guarantees some loss
Of data, this feature is for now restricted to a read-only import.
Reviewed by: George Wilson <george.wilson@delphix.com>
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Reviewed by: Andrew Stormont <andyjstormont@gmail.com>
Approved by: Hans Rosenfeld <rosenfeld@grumpf.hope-2000.org>
Author: Pavel Zakharov <pavel.zakharov@delphix.com>
Some work has been done lately to improve the debugability of the ZFS pool
load (and import) process. This includes:
https://www.illumos.org/issues/7638: Refactor spa_load_impl into several functions
https://www.illumos.org/issues/8961: SPA load/import should tell us why it failed
https://www.illumos.org/issues/7277: zdb should be able to print zfs_dbgmsg's
To iterate on top of that, there's a few changes that were made to make the
import process more resilient and crash free. One of the first tasks during the
pool load process is to parse a config provided from userland that describes
what devices the pool is composed of. A vdev tree is generated from that config,
and then all the vdevs are opened.
The Meta Object Set (MOS) of the pool is accessed, and several metadata objects
that are necessary to load the pool are read. The exact configuration of the
pool is also stored inside the MOS. Since the configuration provided from
userland is external and might not accurately describe the vdev tree
of the pool at the txg that is being loaded, it cannot be relied upon to safely
operate the pool. For that reason, the configuration in the MOS is read early
on. In the past, the two configurations were compared together and if there was
a mismatch then the load process was aborted and an error was returned.
The latter was a good way to ensure a pool does not get corrupted, however it
made the pool load process needlessly fragile in cases where the vdev
configuration changed or the userland configuration was outdated. Since the MOS
is stored in 3 copies, the configuration provided by userland doesn't have to be
perfect in order to read its contents. Hence, a new approach has been adopted:
The pool is first opened with the untrusted userland configuration just so that
the real configuration can be read from the MOS. The trusted MOS configuration
is then used to generate a new vdev tree and the pool is re-opened.
When the pool is opened with an untrusted configuration, writes are disabled
to avoid accidentally damaging it. During reads, some sanity checks are
performed on block pointers to see if each DVA points to a known vdev;
when the configuration is untrusted, instead of panicking the system if those
checks fail we simply avoid issuing reads to the invalid DVAs.
This new two-step pool load process now allows rewinding pools accross
vdev tree changes such as device replacement, addition, etc. Loading a pool
from an external config file in a clustering environment also becomes much
safer now since the pool will import even if the config is outdated and didn't,
for instance, register a recent device addition.
With this code in place, it became relatively easy to implement a
long-sought-after feature: the ability to import a pool with missing top level
(i.e. non-redundant) devices. Note that since this almost guarantees some loss
Of data, this feature is for now restricted to a read-only import.
Reviewed by: George Wilson <george.wilson@delphix.com>
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Reviewed by: Andrew Stormont <andyjstormont@gmail.com>
Approved by: Hans Rosenfeld <rosenfeld@grumpf.hope-2000.org>
Author: Pavel Zakharov <pavel.zakharov@delphix.com>
Reported on the ZFSonLinux https://github.com/zfsonlinux/zfs/issues/4843,
fixed by https://github.com/zfsonlinux/zfs/pull/6339:
If we are in the middle of an incremental zfs receive, the child .../%recv
will exist. If you concurrently run zfs promote .../%recv, it will "work",
but then zfs gets confused. For example, there's no obvious way to destroy
the containing filesystem (because it is now a clone of its invisible child).
Attempting to do this promote should be an error. We could fix this by
having zfs_ioc_promote() check if zc_name contains a %, similar to
zfs_ioc_rename().
Reviewed by: Paul Dagnelie <pcd@delphix.com>
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Approved by: Dan McDonald <danmcd@joyent.com>
Author: loli10K <ezomori.nozomu@gmail.com>
When replacing a faulted device which was previously handled by a spare
multiple levels of nested interior VDEVs will be present in the pool
configuration: get_replication() needs to handle this situation gracefully
to let zpool add new devices to the pool
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Reviewed by: Andrew Stormont <andyjstormont@gmail.com>
Approved by: Dan McDonald <danmcd@joyent.com>
Author: loli10K <ezomori.nozomu@gmail.com>
Illumos 4080 allows "zpool clear" to work on readonly pools: i don't think
this is the intended behaviour, we shouldn't be allowed to clear readonly
pools. Probably.
When iterating over the input nvlist in dsl_props_set_sync_impl() when we
don't preserve the nvpair name before looking up ZPROP_VALUE, so when we
later go to process it nvpair_name() is always "value" instead of the actual
property name.
This results in a couple of bugs in the recv code:
- received properties are not restored correctly when failing to receive
an incremental send stream
- received properties are not completely replaced by the new ones when
successfully receiving an incremental send stream
Reviewed by: Yuri Pankov <yuripv@yuripv.net>
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Approved by: Dan McDonald <danmcd@joyent.com>
Author: Toomas Soome <tsoome@me.com>
Reviewed by: Yuri Pankov <yuripv@yuripv.net>
Reviewed by: Andy Fiddaman <omnios@citrus-it.co.uk>
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Approved by: Dan McDonald <danmcd@joyent.com>
Author: Toomas Soome <tsoome@me.com>
Currently `zdb` consistently fails to examine non-idle pools as it fails
during the `spa_load()` process. The main problem seems to be that
`spa_load_verify()` fails as can be seen below:
ZFS_DBGMSG(zdb):
spa_open_common: opening dcenter
spa_load(dcenter): LOADING
disk vdev '/dev/dsk/c4t11d0s0': best uberblock found for spa dcenter. txg 40824950
spa_load(dcenter): using uberblock with txg=40824950
spa_load(dcenter): UNLOADING
spa_load(dcenter): RELOADING
spa_load(dcenter): LOADING
disk vdev '/dev/dsk/c3t10d0s0': best uberblock found for spa dcenter. txg 40824952
spa_load(dcenter): using uberblock with txg=40824952
spa_load(dcenter): FAILED: spa_load_verify failed [error=5]
spa_load(dcenter): UNLOADING
This change makes `spa_load_verify()` a dryrun when ran from `zdb`. This is
done by creating a global flag in zfs and then setting it in `zdb`.
Reviewed by: George Wilson <george.wilson@delphix.com>
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Reviewed by: Andy Stormont <astormont@racktopsystems.com>
Approved by: Dan McDonald <danmcd@joyent.com>
Author: Pavel Zakharov <pavel.zakharov@delphix.com>
When we fail to open or import a storage pool, we typically don't get any
additional diagnostic information, just "no pool found" or "can not import".
While there may be no additional user-consumable information, we should at
least make this situation easier to debug/diagnose for developers and support.
For example, we could start by using `zfs_dbgmsg()` to log each thing that we
try when importing, and which things failed. E.g. "tried uberblock of txg X
from label Y of device Z". Also, we could log each of the stages that we go
through in `spa_load_impl()`.
Reviewed by: George Wilson <george.wilson@delphix.com>
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Reviewed by: Andrew Stormont <andyjstormont@gmail.com>
Approved by: Dan McDonald <danmcd@joyent.com>
Author: Pavel Zakharov <pavel.zakharov@delphix.com>
spa_load_impl has grown out of proportions. It is currently over 700
lines long and makes it very hard to follow or debug the import process
even for experienced ZFS developers. The objective is to split it up
in a series of well commented functions.
Reviewed by: Paul Dagnelie <pcd@delphix.com>
Reviewed by: George Wilson <george.wilson@delphix.com>
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Reviewed by: Andrew Stormont <andyjstormont@gmail.com>
Approved by: Dan McDonald <danmcd@joyent.com>
Author: Pavel Zakharov <pavel.zakharov@delphix.com>
To prevent kmem_cache reaping from blocking other system resources, turn
kmem_cache_reap_now() (which blocks) into kmem_cache_reap_soon(). Callers
to kmem_cache_reap_soon() should use kmem_cache_reap_active(), which
exploits #9017's new taskq_empty().
Reviewed by: Bryan Cantrill <bryan@joyent.com>
Reviewed by: Dan McDonald <danmcd@joyent.com>
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Reviewed by: Yuri Pankov <yuripv@yuripv.net>
Author: Tim Kordas <tim.kordas@joyent.com>
Reviewed by: Sebastien Roy <sebastien.roy@delphix.com>
Reviewed by: Prakash Surya <prakash.surya@delphix.com>
Reviewed by: Gordon Ross <gordon.w.ross@gmail.com>
Approved by: Richard Lowe <richlowe@richlowe.net>
Author: Andrew Stormont <astormont@racktopsystems.com>
At present it is possible to boot from a root pool that is on RAIDZ but not
one that is on RAIDZ2 or RAIDZ3. This is because, at the time the pool
version is checked to ensure support for dual/triple parity, the uberblock
has not yet been loaded into the SPA and therefore the code determines that
the pool version is too old and returns ENOTSUP.
Reviewed by: Igor Kozhukhov <igor@dilos.org>
Reviewed by: Andriy Gapon <avg@FreeBSD.org>
Reviewed by: Pavel Zakharov <pavel.zakharov@delphix.com>
Reviewed by: Andy Stormont <astormont@racktopsystems.com>
Reviewed by: Toomas Soome <tsoome@me.com>
Approved by: Gordon Ross <gwr@nexenta.com>
Author: Andy Fiddaman <omnios@citrus-it.co.uk>
https://www.illumos.org/issues/8520
lzc_rollback_to() should support rolling back to a clone's origin.
The current checks in zfs_ioc_rollback() would not allow that because the
origin snapshot belongs to a different filesystem.
The overly restrictive check was introduced in 7600, but it was not a
regression as none of the existing tools provided a way to rollback to the
origin.
https://www.illumos.org/issues/7198
EINVAL is returned when a dataset does not have any snapshots, so there is
nothing to roll back to.
Although the code in zfs_do_rollback checks for that condition in advance, it's
still possible that the snapshot(s) gets removed after the check and before the
rollback sync task is executed.
At the moment zfs command would crash when that happens.
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Approved by: Dan McDonald <danmcd@joyent.com>
Author: Andriy Gapon <avg@FreeBSD.org>
https://www.illumos.org/issues/8997
When dmu_tx_assign is called from zil_lwb_write_issue, it's possible
for either ERESTART or EIO to be returned.
If ERESTART is returned, this will cause an assertion to fail directly
in zil_lwb_write_issue, where the code assumes the return value is
EIO if dmu_tx_assign returns a non-zero value. This can occur if the
SPA is suspended when dmu_tx_assign is called, and most often occurs
when running zloop.
If EIO is returned, this can cause assertions to fail elsewhere in the
ZIL code. For example, zil_commit_waiter_timeout contains the
following logic:
lwb_t *nlwb = zil_lwb_write_issue(zilog, lwb);
ASSERT3S(lwb->lwb_state, !=, LWB_STATE_OPENED);
In this case, if dmu_tx_assign returned EIO from within
zil_lwb_write_issue, the lwb variable passed in will not be issued
to disk. Thus, it's lwb_state field will remain LWB_STATE_OPENED and
this assertion will fail. zil_commit_waiter_timeout assumes that after
it calls zil_lwb_write_issue, the lwb will be issued to disk, and
doesn't handle the case where this is not true; i.e. it doesn't handle
the case where dmu_tx_assign returns EIO.
Reviewed by: Matt Ahrens <mahrens@delphix.com>
Reviewed by: Andriy Gapon <avg@FreeBSD.org>
Approved by: Robert Mustacchi <rm@joyent.com>
Author: Prakash Surya <prakash.surya@delphix.com>
https://www.illumos.org/issues/8731
annotate_ecksum() asserts that nui64s, calculated as nui64s = size / sizeof
(uint64_t), is not greater than UINT16_MAX.
This restriction is needed because histograms of incorrectly set and cleared
bits have 16 bit counters and if the buffer consists of too many 64-bit words,
then a counter can potentially overflow producing an incorrect result.
When the largest buffer size was 128KB the greatest value of nui64s was 16K,
well within the limit.
But now we have support for large buffers and for buffer sizes of 512KB and
above the restriction is violated.
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Approved by: Dan McDonald <danmcd@joyent.com>
Author: Andriy Gapon <avg@FreeBSD.org>
https://www.illumos.org/issues/7614:
This project allows top-level vdevs to be removed from the storage pool with
“zpool remove”, reducing the total amount of storage in the pool. This
operation copies all allocated regions of the device to be removed onto other
devices, recording the mapping from old to new location. After the removal is
complete, read and free operations to the removed (now “indirect”) vdev must
be remapped and performed at the new location on disk. The indirect mapping
table is kept in memory whenever the pool is loaded, so there is minimal
performance overhead when doing operations on the indirect vdev.
The size of the in-memory mapping table will be reduced when its entries
become “obsolete” because they are no longer used by any block pointers in
the pool. An entry becomes obsolete when all the blocks that use it are
freed. An entry can also become obsolete when all the snapshots that
reference it are deleted, and the block pointers that reference it have been
“remapped” in all filesystems/zvols (and clones). Whenever an indirect block
is written, all the block pointers in it will be “remapped” to their new
(concrete) locations if possible. This process can be accelerated by using
the “zfs remap” command to proactively rewrite all indirect blocks that
reference indirect (removed) vdevs.
Note that when a device is removed, we do not verify the checksum of the data
that is copied. This makes the process much faster, but if it were used on
redundant vdevs (i.e. mirror or raidz vdevs), it would be possible to copy
the wrong data, when we have the correct data on e.g. the other side of the
mirror. Therefore, mirror and raidz devices can not be removed.
Reviewed by: Alex Reece <alex@delphix.com>
Reviewed by: George Wilson <george.wilson@delphix.com>
Reviewed by: John Kennedy <john.kennedy@delphix.com>
Reviewed by: Prakash Surya <prakash.surya@delphix.com>
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Reviewed by: Richard Laager <rlaager@wiktel.com>
Reviewed by: Tim Chase <tim@chase2k.com>
Approved by: Garrett D'Amore <garrett@damore.org>
Author: Prashanth Sreenivasa <pks@delphix.com>
It panicked here:
http://src.illumos.org/source/xref/illumos-gate/usr/src/uts/common/fs/zfs/
zio.c#430
pio->io_lock is DEAD, thus a panic. Further analysis shows the "pio"
(parent zio of "cio") has already been destroyed.
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Reviewed by: Andriy Gapon <avg@FreeBSD.org>
Reviewed by: Youzhong Yang <youzhong@gmail.com>
Approved by: Dan McDonald <danmcd@omniti.com>
Author: George Wilson <george.wilson@delphix.com>
https://www.illumos.org/issues/8972:
'zfs holds -H' does not properly output content in scripted mode. It uses a
tab instead of two spaces, but it still pads column widths with spaces when
it should not.
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Approved by: Dan McDonald <danmcd@joyent.com>
Author: Allan Jude <allanjude@freebsd.org>
https://www.illumos.org/issues/8835:
Sequential reads not aligned to block size are not detected by ZFS
prefetcher as sequential, killing prefetch and severely hurting
performance. It is caused by dmu_zfetch() in case of misaligned
sequential accesses being called with overlap of one block.
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Reviewed by: Allan Jude <allanjude@freebsd.org>
Approved by: Gordon Ross <gwr@nexenta.com>
Author: Alexander Motin <mav@FreeBSD.org>
https://www.illumos.org/issues/8652:
Clang and GCC prefer to use unsigned ints to store enums. With Clang, that
causes tautological comparison warnings when comparing a zfs_prop_t or
zpool_prop_t variable to the macro ZPROP_INVAL. It's likely that error
handling code is being silently removed as a result.
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Reviewed by: Igor Kozhukhov <igor@dilos.org>
Approved by: Gordon Ross <gwr@nexenta.com>
Author: Alan Somers <asomers@gmail.com>
https://www.illumos.org/issues/8641:
"zpool clear" and "zinject -d" can both operate on specific vdevs, either
leaf or interior. However, due to an oversight, neither works on a "spare"
or "replacing" vdev. For example:
sudo zpool create foo raidz1 c1t5000CCA000081D61d0 c1t5000CCA000186235d0 spare c1t5000CCA000094115d0
sudo zpool replace foo c1t5000CCA000186235d0 c1t5000CCA000094115d0
$ zpool status foo pool: foo
state: ONLINE
scan: resilvered 81.5K in 0h0m with 0 errors on Fri Sep 8 10:53:03 2017
config:
NAME STATE READ WRITE CKSUM
foo ONLINE 0 0 0
raidz1-0 ONLINE 0 0 0
c1t5000CCA000081D61d0 ONLINE 0 0 0
spare-1 ONLINE 0 0 0
c1t5000CCA000186235d0 ONLINE 0 0 0
c1t5000CCA000094115d0 ONLINE 0 0 0
spares
c1t5000CCA000094115d0 INUSE currently in use
$ sudo zinject -d spare-1 -A degrade foo
cannot find device 'spare-1' in pool 'foo'
$ sudo zpool clear foo spare-1
cannot clear errors for spare-1: no such device in pool
Even though there was nothing to clear, those commands shouldn't have
reported an error. by contrast, trying to clear "raidz1-0" works just fine:
$ sudo zpool clear foo raidz1-0
Reviewed by: Alek Pinchuk <pinchuk.alek@gmail.com>
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Approved by: Gordon Ross <gwr@nexenta.com>
Author: Sean Eric Fagan <sef@ixsystems.com>
https://www.illumos.org/issues/8856:
arc_cksum_is_equal() calls zio_push_transform() that requires abd_t*
(second arg), but a void* is passed.
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Reviewed by: George Wilson <george.wilson@delphix.com>
Approved by: Gordon Ross <gwr@nexenta.com>
Author: Roman Strashkin <roman.strashkin@nexenta.com>
https://www.illumos.org/issues/8898:
# zfs create -o checksum=skein rpool/test
internal error: Result too large
Abort (core dumped)
Not a big deal per se, but should be handled correctly.
Also reported as: https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=222199
Reviewed by: Toomas Soome <tsoome@me.com>
Reviewed by: Andy Stormont <astormont@racktopsystems.com>
Approved by: Dan McDonald <danmcd@joyent.com>
Author: Yuri Pankov <yuri.pankov@nexenta.com>
https://www.illumos.org/issues/8897:
# zpool online -e test mirror-1
Assertion failed: nvlist_lookup_string(tgt, "path", &pathname) == 0, file ../common/libzfs_pool.c, line 2558, function zpool_vdev_online
Abort (core dumped)
Not a big deal per se, but should be handled gracefully, same way as 'offline' and 'online' without '-e'.
Also reported as: https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=221408
Reviewed by: Toomas Soome <tsoome@me.com>
Reviewed by: Igor Kozhukhov <igor@dilos.org>
Approved by: Dan McDonald <danmcd@joyent.com>
Author: Yuri Pankov <yuri.pankov@nexenta.com>
https://www.illumos.org/issues/8930:
We normally remove an unlinked node when its last user goes away and the
node becomes inactive. However, we should not do that if the filesystem
is mounted read-only including the case where it has its readonly
property set. The node will remain on the unlinked queue, so it will
not be leaked.
One particular scenario is when we receive an incremental stream into a
mounted read-only filesystem and that stream contains an unlinked file
(still on the unlinked queue). If that file is opened before the
receive and some time later after the receive it becomes inactive we
would remove it and, thus, modify the read-only filesystem. As a
result, the filesystem would diverge from its source and further
incremental receives would not be possible (without forcing a rollback).
Another related scenario, that may or may not be possible depending on an
OS / VFS policy, is when an open file is unlinked, then the filesystem is
remounted read-only, and then the file is closed.
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Approved by: Gordon Ross <gwr@nexenta.com>
Author: Andriy Gapon <avg@FreeBSD.org>
https://www.illumos.org/issues/8909:
There's a race condition that exists if `zil_free_lwb` races with either
`zil_commit_waiter_timeout` and/or `zil_lwb_flush_vdevs_done`.
Here's an example panic due to this bug:
> ::status
debugging crash dump vmcore.0 (64-bit) from ip-10-110-205-40
operating system: 5.11 dlpx-5.2.2.0_2017-12-04-17-28-32b6ba51fb (i86pc)
image uuid: 4af0edfb-e58e-6ed8-cafc-d3e9167c7513
panic message:
BAD TRAP: type=e (#pf Page fault) rp=ffffff0010555970 addr=60 occurred in module "zfs" due to a NULL pointer dereference
dump content: kernel pages only
If there's an outstanding lwb that's in `zil_commit_waiter_timeout`
waiting to timeout, waiting on it's waiter's CV, we must be sure not to
call `zil_free_lwb`. If we end up calling `zil_free_lwb`, then that LWB
may be freed and can result in a use-after-free situation where the
stale lwb pointer stored in the `zil_commit_waiter_t` structure of the
thread waiting on the waiter's CV is used.
A similar situation can occur if an lwb is issued to disk, and thus in
the `LWB_STATE_ISSUED` state, and `zil_free_lwb` is called while the
disk is servicing that lwb. In this situation, the lwb will be freed by
`zil_free_lwb`, which will result in a use-after-free situation when the
lwb's zio completes, and `zil_lwb_flush_vdevs_done` is called.
This race condition is prevented in `zil_close` by calling `zil_commit`
before `zil_free_lwb` is called, which will ensure all outstanding (i.e.
all lwb's in the `LWB_STATE_OPEN` and/or `LWB_STATE_ISSUED` states)
reach the `LWB_STATE_DONE` state before the lwb's are freed
(`zil_commit` will not return untill all the lwb's are
`LWB_STATE_DONE`).
Further, this race condition is prevented in `zil_sync` by only calling
`zil_free_lwb` for lwb's that do not have their `lwb_buf` pointer set.
All lwb's not in the `LWB_STATE_DONE` state will have a non-null value
for this pointer; the pointer is only cleared in
`zil_lwb_flush_vdevs_done`, at which point the lwb's state will be
changed to `LWB_STATE_DONE`.
This race is present in `zil_suspend`, leading to this bug.
At first glance, it would appear as though this would not be true
because `zil_suspend` will call `zil_commit`, just like `zil_close`, but
the problem is that `zil_suspend` will set the zilog's `zl_suspend`
field prior to calling `zil_commit`. Further, in `zil_commit`, if
`zl_suspend` is set, `zil_commit` will take a special branch of logic
and use `txg_wait_synced` instead of performing the normal `zil_commit`
logic.
This call to `txg_wait_synced` might be good enough for the data to
reach disk safely before it returns, but it does not ensure that all
outstanding lwb's reach the `LWB_STATE_DONE` state before it returns.
This is because, if there's an lwb "stuck" in
`zil_commit_waiter_timeout`, waiting for it's lwb to timeout, it will
maintain a non-null value for it's `lwb_buf` field and thus `zil_sync`
will not free that lwb. Thus, even though the lwb's data is already on
disk, the lwb will be left lingering, waiting on the CV, and will
eventually timeout and be issued to disk even though the write is
unnesseary.
So, after `zil_commit` is called from `zil_suspend`, we incorrectly
assume that there are not outstanding lwb's, and proceed to free all
lwb's found on the zilog's lwb list. As a result, we free the lwb that
will later be used `zil_commit_waiter_timeout`.
Reviewed by: John Kennedy <jwk404@gmail.com>
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Reviewed by: George Wilson <george.wilson@delphix.com>
Reviewed by: Brad Lewis <brad.lewis@delphix.com>
Reviewed by: Igor Kozhukhov <igor@dilos.org>
Approved by: Robert Mustacchi <rm@joyent.com>
Author: Prakash Surya <prakash.surya@delphix.com>
https://www.illumos.org/issues/8603:
To help make the ZIL's code more understandable, it was suggested that
the zilog_t's "zl_writer_lock" field should be renamed to "zl_issuer_lock".
https://www.illumos.org/issues/8677
We want to be able to run channel programs outside of synching context.
This would greatly improve performance of channel program that just gather
information, as we won't have to wait for synching context anymore.
This feature should introduce the following:
- A new command line flag in "zfs program" to specify our intention to
run in open context.
- A new flag/option within the channel program ioctl which selects the
context.
- Appropriate error handling whenever we try a channel program in
open-context that contains zfs.sync* expressions.
- Documentation for the new feature in the manual pages.
Reviewed by: Matt Ahrens <mahrens@delphix.com>
Reviewed by: Chris Williamson <chris.williamson@delphix.com>
Reviewed by: Pavel Zakharov <pavel.zakharov@delphix.com>
Approved by: Robert Mustacchi <rm@joyent.com>
Author: Serapheim Dimitropoulos <serapheim@delphix.com>
https://www.illumos.org/issues/7531
I found that some buffers that could be L2ARC eligible are not flagged
such, leading to some performance impact. As a test I ran the same IO
workload 10 times in a raw. It is a metadata only workload (files
listing). l2arc_noprefetch=0.
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Reviewed by: Prakash Surya <prakash.surya@delphix.com>
Approved by: Dan McDonald <danmcd@joyent.com>
Author: benrubson <ben.rubson@gmail.com>
Reviewed by: Yuri Pankov <yuripv@gmx.com>
Reviewed by: Igor Kozhukhov <igor@dilos.org>
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Approved by: Robert Mustacchi <rm@joyent.com>
Author: Toomas Soome <tsoome@me.com>
https://www.illumos.org/issues/8713
If we're creating a pool with version >= SPA_VERSION_DSL_SCRUB (v11) we need to
account for additional space needed by the origin dataset which will also be
snapshotted: "poolname"+"/"+"$ORIGIN"+"@"+"$ORIGIN".
Enforce this limit in pool_namecheck().
Reviewed by: Prakash Surya <prakash.surya@delphix.com>
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Approved by: Dan McDonald <danmcd@joyent.com>
Author: loli10K <ezomori.nozomu@gmail.com>
https://www.illumos.org/issues/640
du(1), df(1m), ls(1), and swap(1m) all include a copy (it appears literally
copied) of the 'number_to_scaled_string' function in their source. This should
be moved to a shared library and all 4 commands should use this instead.
Reviewed by: Sebastian Wiedenroth <wiedi@frubar.net>
Reviewed by: Robert Mustacchi <rm@joyent.com>
Reviewed by: Yuri Pankov <yuripv@gmx.com>
Approved by: Dan McDonald <danmcd@joyent.com>
Author: Jason King <jason.brian.king@gmail.com>
https://www.illumos.org/issues/8081
zdb(8) is full of minor problems that generate compiler warnings. On FreeBSD,
which uses -WError, the only way to build it is to disable all compiler
warnings. This makes it much harder to detect newly introduced bugs. We should
cleanup all the warnings.
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Reviewed by: Prakash Surya <prakash.surya@delphix.com>
Approved by: Richard Lowe <richlowe@richlowe.net>
Author: Alan Somers <asomers@gmail.com>
Since OpenZFS 7578 (1b7c1e5) if we have a ZVOL with logbias=throughput
we will force WR_INDIRECT itxs in zvol_log_write() setting itx->itx_lr
offset and length to the offset and length of the BIO from
zvol_write()->zvol_log_write(): these offset and length are later used
to take a range lock in zillog->zl_get_data function: zvol_get_data().
Now suppose we have a ZVOL with blocksize=8K and push 4K writes to
offset 0: we will only be range-locking 0-4096. This means the
ASSERTion we make in dbuf_unoverride() is no longer valid because now
dmu_sync() is called from zilog's get_data functions holding a partial
lock on the dbuf.
Fix this by taking a range lock on the whole block in zvol_get_data().
Reviewed-by: Chunwei Chen <tuxoko@gmail.com> Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov> Signed-off-by: loli10K <ezomori.nozomu@gmail.com>
Reviewed by: Igor Kozhukhov <igor@dilos.org>
Reviewed by: Matt Ahrens <mahrens@delphix.com>
Reviewed by: Andriy Gapon <avg@FreeBSD.org>
Reviewed by: Alexander Motin <mav@FreeBSD.org>
Approved by: Robert Mustacchi <rm@joyent.com>
Author: LOLi <loli10K@users.noreply.github.com>
https://www.illumos.org/issues/8661
The "zil-cw1" dtrace probe was previously removed in 8558, and the "zil-cw2"
probe should have been removed in that patch as well. Unfortunately, the "zil-
cw2" was not removed in 8558, so this bug is to track it's removal.
Reviewed by: Serapheim Dimitropoulos <serapheim@delphix.com>
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Reviewed by: Igor Kozhukhov <igor@dilos.org>
Approved by: Robert Mustacchi <rm@joyent.com>
Author: Prakash Surya <prakash.surya@delphix.com>
https://www.illumos.org/issues/8600
ZFS channel programs should be able to create snapshots.
In addition to the base snapshot functionality, this will likely entail adding
extra logic to handle edge cases which were formerly not possible, such as
creating then destroying a snapshot in the same transaction sync.
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Reviewed by: John Kennedy <john.kennedy@delphix.com>
Reviewed by: Brad Lewis <brad.lewis@delphix.com>
Approved by: Robert Mustacchi <rm@joyent.com>
Author: Chris Williamson <chris.williamson@delphix.com>
https://www.illumos.org/issues/8592
ZFS channel programs should be able to perform a rollback. This logic will
probably look pretty similar to zfs.sync.destroy().
Reviewed by: Chris Williamson <chris.williamson@delphix.com>
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Approved by: Robert Mustacchi <rm@joyent.com>
Author: Brad Lewis <brad.lewis@delphix.com>
https://www.illumos.org/issues/8502
The code in lib/libzfs/common/libzfs_mount.c already basically handles
the case when libshare is not installed. We just need to not fail in
zfs_init_libshare_impl. I tested this in lx and things work as
expected. I also tested there trying to set sharenfs and sharesmb on
the delegated dataset. Neither is allowed from within a zone. The
spew of msgs from a native zone is not ZFS specific. I see the same
spew simply running the share command.
Reviewed by: Robert Mustacchi <rm@joyent.com>
Reviewed by: Yuri Pankov <yuripv@gmx.com>
Approved by: Richard Lowe <richlowe@richlowe.net>
Author: Jerry Jelinek <jerry.jelinek@joyent.com>
https://www.illumos.org/issues/8604
Every time we want to unmount a snapshot (happens during snapshot deletion or
renaming) we unnecessarily iterate through all the mountpoints in the VFS layer
(see zfs_get_vfs).
Ideally we would just put a hold on the snapshot and access its respective VFS
resource directly.
gwilson_snap_unmount.svg - Flamegraph indicating the issue discussed (138 KB)
Serapheim Dimitropoulos, 2017-09-14 06:36 PM
Reviewed by: Matt Ahrens <mahrens@delphix.com>
Reviewed by: George Wilson <george.wilson@delphix.com>
Reviewed by: Andy Stormont <astormont@racktopsystems.com>
Approved by: Robert Mustacchi <rm@joyent.com>
Author: Serapheim Dimitropoulos <serapheim@delphix.com>
https://www.illumos.org/issues/8605
zfs.exists() in channel programs doesn't return any result, and should have a
man page entry.
Reviewed by: Paul Dagnelie <pcd@delphix.com>
Reviewed by: Dan Kimmel <dan.kimmel@delphix.com>
Reviewed by: Matt Ahrens <mahrens@delphix.com>
Approved by: Robert Mustacchi <rm@joyent.com>
Author: Chris Williamson <chris.williamson@delphix.com>
https://www.illumos.org/issues/8602
When I landed the fix for 8558, I incorrectly added the "dp_early_sync_tasks"
field to the "dsl_pool" structure. This field is used in DelphixOS, but not in
illumos. It was incorrectly pulled into illumos, so this bug is to remove it
from the structure.
Reviewed by: Serapheim Dimitropoulos <serapheim@delphix.com>
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Approved by: Robert Mustacchi <rm@joyent.com>
Author: Prakash Surya <prakash.surya@delphix.com>
https://www.illumos.org/issues/8567
If fstat64 fails, pread64 fails, or the label is unintelligible,
zpool_read_label will return 0. But if malloc fails, it will return -1. For
consistency, it should always return -1 on failure or 0 on success.
Reviewed by: Prakash Surya <prakash.surya@delphix.com>
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Approved by: Robert Mustacchi <rm@joyent.com>
Author: Alan Somers <asomers@gmail.com>
https://www.illumos.org/issues/8473
Scrubbing is supposed to detect and repair all errors in the pool. However, it
wrongly ignores active spare devices. The problem can easily be reproduced in
OpenZFS at git rev 0ef125d with these commands:
truncate -s 64m /tmp/a /tmp/b /tmp/c
sudo zpool create testpool mirror /tmp/a /tmp/b spare /tmp/c
sudo zpool replace testpool /tmp/a /tmp/c
/bin/dd if=/dev/zero bs=1024k count=63 oseek=1 conv=notrunc of=/tmp/c
sync
sudo zpool scrub testpool
zpool status testpool # Will show 0 errors, which is wrong
sudo zpool offline testpool /tmp/a
sudo zpool scrub testpool
zpool status testpool # Will show errors on /tmp/c, which should've already been fixed
FreeBSD head is partially affected: the first scrub will detect some errors,
but the second scrub will detect more.
Reviewed by: Andy Stormont <astormont@racktopsystems.com>
Reviewed by: Matt Ahrens <mahrens@delphix.com>
Reviewed by: George Wilson <george.wilson@delphix.com>
Approved by: Richard Lowe <richlowe@richlowe.net>
Author: Alan Somers <asomers@gmail.com>
https://www.illumos.org/issues/8585
The current implementation of zil_commit() can introduce significant
latency, beyond what is inherent due to the latency of the underlying
storage. The additional latency comes from two main problems:
1. When there's outstanding ZIL blocks being written (i.e. there's
already a "writer thread" in progress), then any new calls to
zil_commit() will block waiting for the currently oustanding ZIL
blocks to complete. The blocks written for each "writer thread" is
coined a "batch", and there can only ever be a single "batch" being
written at a time. When a batch is being written, any new ZIL
transactions will have to wait for the next batch to be written,
which won't occur until the current batch finishes.
As a result, the underlying storage may not be used as efficiently
as possible. While "new" threads enter zil_commit() and are blocked
waiting for the next batch, it's possible that the underlying
storage isn't fully utilized by the current batch of ZIL blocks. In
that case, it'd be better to allow these new threads to generate
(and issue) a new ZIL block, such that it could be serviced by the
underlying storage concurrently with the other ZIL blocks that are
being serviced.
2. Any call to zil_commit() must wait for all ZIL blocks in its "batch"
to complete, prior to zil_commit() returning. The size of any given
batch is proportional to the number of ZIL transaction in the queue
at the time that the batch starts processing the queue; which
doesn't occur until the previous batch completes. Thus, if there's a
lot of transactions in the queue, the batch could be composed of
many ZIL blocks, and each call to zil_commit() will have to wait for
all of these writes to complete (even if the thread calling
zil_commit() only cared about one of the transactions in the batch).
Reviewed by: Brad Lewis <brad.lewis@delphix.com>
Reviewed by: Matt Ahrens <mahrens@delphix.com>
Reviewed by: George Wilson <george.wilson@delphix.com>
Approved by: Dan McDonald <danmcd@joyent.com>
Author: Prakash Surya <prakash.surya@delphix.com>
https://www.illumos.org/issues/8590
In dsl_destroy_snapshots_nvl(), "snaps_normalized" is not freed after it is
added to "arg".
Reviewed by: Pavel Zakharov <pavel.zakharov@delphix.com>
Reviewed by: Steve Gonczi <steve.gonczi@delphix.com>
Reviewed by: George Wilson <george.wilson@delphix.com>
Approved by: Dan McDonald <danmcd@joyent.com>
Author: Matthew Ahrens <mahrens@delphix.com>
https://www.illumos.org/issues/8552
In the LUA interpreter used by "zfs program", the lua format() function
accidentally includes support for '%f' and friends, which can cause compilation
problems when building on platforms that don't support floating-point math in
the kernel (e.g. sparc). Support for '%f' friends (%f %e %E %g %G) should be
removed, since there's no way to supply a floating-point value anyway (all
numbers in ZFS LUA are int64_t's).
Reviewed by: Yuri Pankov <yuripv@gmx.com>
Reviewed by: Igor Kozhukhov <igor@dilos.org>
Approved by: Dan McDonald <danmcd@joyent.com>
Author: Matthew Ahrens <mahrens@delphix.com>
Reviewed by: Steve Gonczi <steve.gonczi@delphix.com>
Reviewed by: George Wilson <george.wilson@delphix.com>
Reviewed by: Yuri Pankov <yuripv@gmx.com>
Reviewed by: Matt Ahrens <mahrens@delphix.com>
Approved by: Dan McDonald <danmcd@joyent.com>
Author: Pavel Zakharov <pavel.zakharov@delphix.com>
https://www.illumos.org/issues/7431
ZFS channel programs (ZCP) adds support for performing compound ZFS
administrative actions via Lua scripts in a sandboxed environment (with time
and memory limits).
This initial commit includes both base support for running ZCP scripts, and a
small initial library of API calls which support getting properties and
listing, destroying, and promoting datasets.
Testing: in addition to the included unit tests, channel programs have been in
use at Delphix for several months for batch destroying filesystems. The
dsl_destroy_snaps_nvl() call has also been replaced with
For reference, the new zfs-program manpage is included below.
ZFS-PROGRAM(1M) 1M ZFS-PROGRAM(1M)
NAME
zfs program – executes ZFS channel programs
SYNOPSIS
zfs program [-t timeout] [-m memory-limit] pool script
DESCRIPTION
The ZFS channel program interface allows ZFS administrative operations to
be run programmatically as a Lua script. The entire script is executed
atomically, with no other administrative operations taking effect
concurrently. A library of ZFS calls is made available to channel program
scripts. Channel programs may only be run with root privileges.
A modified version of the Lua 5.2 interpreter is used to run channel
program scripts. The Lua 5.2 manual can be found at:
http://www.lua.org/manual/5.2/
...
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Reviewed by: George Wilson <george.wilson@delphix.com>
Reviewed by: John Kennedy <john.kennedy@delphix.com>
Reviewed by: Dan Kimmel <dan.kimmel@delphix.com>
Approved by: Garrett D'Amore <garrett@damore.org>
Author: Chris Williamson <chris.williamson@delphix.com>
https://www.illumos.org/issues/5115
Intel's NICs based on the XL710 chipset exist 1 . There exist drivers for Linux
and FreeBSD 2 .
It does not appear to be derived from the ixgbe driver source, so it would
probably require porting the i40e source from FBSD to Illumos, unless a driver
exists for a GLDv3-like platform under CDDL or similar license (none are known
to currently be available or being worked on).
Reviewed by: Dan McDonald <danmcd@omniti.com>
Reviewed by: Hans Rosenfeld <rosenfeld@grumpf.hope-2000.org>
Approved by: Richard Lowe <richlowe@richlowe.net>
Author: Robert Mustacchi <rm@joyent.com>
https://www.illumos.org/issues/5815
When panic() is called from within ztest, the mdb ::status command isn't as
useful as it could be since the global panicstr variable isn't updated. We
should modify the function to make sure panicstr is set, so ::status can
present the error message just like it does on a failed assertion.
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Reviewed by: Sebastien Roy <sebastien.roy@delphix.com>
Reviewed by: Gordon Ross <gordon.ross@nexenta.com>
Reviewed by: Rich Lowe <richlowe@richlowe.net>
Approved by: Dan McDonald <danmcd@omniti.com>
Author: Prakash Surya <prakash.surya@delphix.com>
https://www.illumos.org/issues/8376
The logic for generating and maintaining the cached v_path value on vnodes
could stand to be improved. If vnodes were purely ephemeral, then freshly
calculating v_path at the time of lookup() would result in correct values (at a
performance cost). When they persist, either as referenced by other structures
(such as open files, process cwd, dnlc entries, etc), the opportunity for the
v_path to become stale arises. This is exacerbated by the current behavior
that, when v_path is found to be invalid (during a vnodetopath operation) will
strive to recalculate it, but not preserve the result. The overall situation
leads to both performance and correctness (due to lack of results) problems
relating to v_path.
This has been addressed in SmartOS through a series of changes. Firstly, to do
proper invalidation of v_path when it's found to be stale:
- OS-3891 stale v_path slows vfs lookups
OS-3891 revealed that some logic made assumptions about v_path never
transitioning from non-NULL to NULL. It was addressed here:
- OS-4317 v_path accesses can race
While the pathological stale v_path behavior had been addressed, there are
still cases where the absence of valid v_path information was causing problems.
The largest patch in this series addressed it by performing v_path checking and
updates during vnode lookups/updates, when it is most convenient:
- OS-5167 cached v_path should be kept fresh
Two smaller updates are included too, to prevent erroneous behavior introduced
by the prior changes:
- OS-5846 procfs should follow VFS rules
- OS-6134 vn_reinit balks on zeroed vnodes
Reviewed by: Jerry Jelinek <jerry.jelinek@joyent.com>
Reviewed by: Robert Mustacchi <rm@joyent.com>
Approved by: Gordon Ross <gwr@nexenta.com>
Author: Patrick Mooney <pmooney@pfmooney.com>
https://www.illumos.org/issues/8331
zfs_unshare returns EZFS_UNSHARENFSFAILED on error for all share types.
Reviewed by: Marcel Telka <marcel@telka.sk>
Reviewed by: Toomas Soome <tsoome@me.com>
Approved by: Dan McDonald <danmcd@omniti.com>
Author: Andrew Stormont <astormont@racktopsystems.com>
https://www.illumos.org/issues/8569
C [C99] has peculiar rules for inline functions that are different from the
C++ rules. Unlike C++ where inline is "fire and forget", in C a programmer
must pay attention to the function's storage class / visibility. The main
problem is with the case where a compiler decides to not inline a call to the
function declared as inline.
Some relevant links:
- http://infocenter.arm.com/help/index.jsp?topic=/com.arm.doc.faqs/ka15831.html
- http://www.drdobbs.com/the-new-c-inline-functions/184401540
The summary is that either the inline functions should be declared 'static
inline' or one of the compilation units (.c files) must provide a callable
externally visible function definition. In the former case, the compiler would
automatically create a local non-inlined function instance in every compilation
unit where it's needed. In the latter case the single external definition is
used to satisfy any non-inlined calls in all compilation units. As things
stand right now, we can get an undefined reference error under certain
combinations of compilers and compiler options. For example, this is what I
get on FreeBSD when compiling with clang 4.0.0 and -O1:
In function `abd_free': /usr/src/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/abd.c:385:
undefined reference to `abd_is_linear'
So, there are two alternatives. Either to qualify each inline function in
abd.h with static storage class. Or to add declarations like the following to
abd.c: extern inline boolean_t abd_is_linear(abd_t *abd); Both work. I am not
sure which one would be more consistent with the illumos development rules.
Reviewed by: Matt Ahrens <mahrens@delphix.com>
Approved by: Robert Mustacchi <rm@joyent.com>
Author: Andriy Gapon <avg@FreeBSD.org>
https://www.illumos.org/issues/8558
On a system with more than 80K ZFS filesystems, we've seen cases where
lwp_create() will start to fail by returning EAGAIN. The problem being,
for each of those 80K ZFS filesystems, a taskq will be created for each
dataset as part of the ZIL for each dataset.
For each of these taskq's, a kernel thread will be created which results
in 24KB being allocated for each thread. With enough of these 24KB
allocations, we eventually exhaust the memory region set aside for these
allocations. Currently, segkpsize is set to a value of 2GB, which means
we can only support about 80K filesystems; 2GB / 24KB = ~80K.
The lwp_create() failure comes into play due to the fact that LWP
creation also allocates 24KB from this same region of memory. Thus, if
we've exhausted this region of memory due to the number of ZIL taskq's,
there won't be any memory avaible to allow the call to lwp_create() to
succeed.
Reviewed by: George Wilson <george.wilson@delphix.com>
Reviewed by: Sebastien Roy <sebastien.roy@delphix.com>
Approved by: Robert Mustacchi <rm@joyent.com>
Author: Prakash Surya <prakash.surya@delphix.com>
https://www.illumos.org/issues/8435
This commit is a result of re-read while porting zpool.1m to ZFSonLinux.
See https://github.com/zfsonlinux/zfs/commit/ cda0317e4d2a1277b328e4fc42ee3699bbe46c12
https://www.illumos.org/issues/3796
The listsnapshots property is not documented in the zpool man page.
3796 listsnapshots not documented in zpool man page
Reviewed by: Matt Ahrens <mahrens@delphix.com>
Reviewed by: Yuri Pankov <yuripv@gmx.com>
Approved by: Dan McDonald <danmcd@joyent.com>
Author: George Melikov <mail@gmelikov.ru>
https://www.illumos.org/issues/8414
This issue tracks the port of scrub pause from ZoL: https://github.com/zfsonlinux/zfs/pull/6167
Currently, there is no way to pause a scrub. Pausing may be useful when
the pool is busy with other I/O to preserve bandwidth.
Description
This patch adds the ability to pause and resume scrubbing. This is achieved
by maintaining a persistent on-disk scrub state. While the state is 'paused'
we do not scrub any more blocks. We do however perform regular scan
housekeeping such as freeing async destroyed and deadlist blocks while paused.
If you're testing this change, you probably want to include the patch from #6164
Motivation and Context
Scrub pausing can be an I/O intensive operation and people have been asking
for the ability to pause a scrub for a while. This allows one to preserve scrub
progress while freeing up bandwidth for other I/O.
How Has This Been Tested?
Unit testing and zfs-tests. to the pool. This patch will also include the
patch from https://github.com/zfsonlinux/zfs/ pull/6164 In certain cases
(dsl_scan_sync() is one), we may end up calling
Reviewed by: George Melikov <mail@gmelikov.ru>
Reviewed by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed by: Brad Lewis <brad.lewis@delphix.com>
Reviewed by: Serapheim Dimitropoulos <serapheim@delphix.com>
Reviewed by: Matt Ahrens <mahrens@delphix.com>
Approved by: Dan McDonald <danmcd@joyent.com>
Author: Alek Pinchuk <apinchuk@datto.com>
https://www.illumos.org/issues/8547
update mandoc (now it's the official name) suite to new upstream version, which
among a lot of fixes, brings in much improved eqn(5)/tbl(5) support.
Reviewed by: Robert Mustacchi <rm@joyent.com>
Approved by: Richard Lowe <richlowe@richlowe.net>
Author: Yuri Pankov <yuri.pankov@nexenta.com>
https://www.illumos.org/issues/8300
Prior to integrating the mdocml update to 1.14.1, fix issues found by new
version, especially the "new sentence, new line" style rule.
Reviewed by: Robert Mustacchi <rm@joyent.com>
Reviewed by: Toomas Soome <tsoome@me.com>
Approved by: Gordon Ross <gwr@nexenta.com>
Author: Yuri Pankov <yuri.pankov@nexenta.com>
https://www.illumos.org/issues/8138
While reading man pages, I've noticed a number of spelling mistakes
and simple typos we should fix.
Reviewed by: Toomas Soome <tsoome@me.com>
Reviewed by: Cody Mello <melloc@joyent.com>
Reviewed by: Patrick Mooney <patrick.mooney@joyent.com>
Approved by: Robert Mustacchi <rm@joyent.com>
Author: Peter Tribble <peter.tribble@gmail.com>
https://www.illumos.org/issues/8508
Mounting a zpool on a 32-bit system triggers a panic in spa_history_log_version
() due to a type format mismatch for ZPL_VERSION. ZPL_VERSION is a unsigned
long long, but the format expects an integer. On 64-bit platforms this may not
be an issue due to word size and alignment. On 32-bit platforms a word size is
half that of a long long, causing the second word of the long long to be seen
as the string pointer for utsname.nodename.
Reviewed by: Matt Ahrens <mahrens@delphix.com>
Approved by: Dan McDonald <danmcd@joyent.com>
Author: Justin Hibbits <chmeeedalf@gmail.com>
https://www.illumos.org/issues/8373
The code that writes ZIL blocks uses dmu_tx_assign(TXG_WAIT) to assign a
transaction to a transaction group.
That seems to be logically incorrect as writing of the ZIL block does not
introduce any new dirty data.
Also, when there is a lot of dirty data, the call can introduce significant
delays into the ZIL commit path,
thus affecting all synchronous writes. Additionally, ARC throttling may affect
the ZIL writing.
We probably need a new mechanism similar to dmu_tx_create_assigned to assign
ZIL transactions.
(Ab)using TXG_WAITED does not seem to be sufficient.
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Reviewed by: Prakash Surya <prakash.surya@delphix.com>
Approved by: Dan McDonald <danmcd@joyent.com>
Author: Andriy Gapon <avg@FreeBSD.org>
https://www.illumos.org/issues/8491
The zpool checkpoint feature in DxOS added a new field in the uberblock.
The Multi-Modifier Protection Pull Request from ZoL adds two new fields in the
uberblock (Reference: https://github.com/zfsonlinux/zfs/pull/6279).
As these two changes come from two different sources and once upstreamed and
deployed will introduce an incompatibility with each other we want
to upstream a change that will reserve the padding for both of them so
integration goes smoothly and everyone gets both features.
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Reviewed by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed by: Olaf Faaland <faaland1@llnl.gov>
Approved by: Gordon Ross <gwr@nexenta.com>
Author: Serapheim Dimitropoulos <serapheim@delphix.com>
https://www.illumos.org/issues/7915
l2arc_evict() is strictly serialized with respect to l2arc_write_buffers() and
l2arc_write_done().
Normally, l2arc_evict() and l2arc_write_buffers() are called from the same
thread, so they can not be concurrent.
Also, l2arc_write_buffers() uses zio_wait() on the parent zio of all cache zio-
s.
That ensures that l2arc_write_done() is completed before l2arc_write_buffers()
returns.
Finally, if a cache device is removed, then l2arc_evict() is called under
SCL_ALL in the exclusive mode.
That ensures that it can not be concurrent with the normal L2ARC accesses to
the device (including writing and evicting buffers).
Given the above, some checks and actions in l2arc_evict() do not make sense.
For instance, it must never encounter the write head header let alone remove it
from the buffer list.
Reviewed by: Dan Kimmel <dan.kimmel@delphix.com>
Reviewed by: Prakash Surya <prakash.surya@delphix.com>
Approved by: Matthew Ahrens <mahrens@delphix.com>
Author: Andriy Gapon <avg@FreeBSD.org>
https://www.illumos.org/issues/8126
The sync thread is concurrently modifying dn_phys->dn_nlevels
while dbuf_dirty() is trying to assert something about it, without
holding the necessary lock. We need to move this assertion further down
in the function, after we have acquired the dn_struct_rwlock.
Reviewed by: Pavel Zakharov <pavel.zakharov@delphix.com>
Reviewed by: Serapheim Dimitropoulos <serapheim@delphix.com>
Approved by: Robert Mustacchi <rm@joyent.com>
Author: Matthew Ahrens <mahrens@delphix.com>
https://www.illumos.org/issues/8067
Add an option to zdb to print a literal embedded block pointer supplied on the
command line:
zdb -E [-A] word0:word1:...:word15
Reviewed by: George Wilson <george.wilson@delphix.com>
Reviewed by: Alex Reece <alex@delphix.com>
Reviewed by: Yuri Pankov <yuri.pankov@gmail.com>
Approved by: Robert Mustacchi <rm@joyent.com>
Author: Matthew Ahrens <mahrens@delphix.com>
https://www.illumos.org/issues/8426
abd_copy_from_buf and abd_cmp_buf do not modify their void *buf arguments, so
qualify them with const.
abd_copy_from_buf_off and abd_cmp_buf_off already had that type for the
corresponding arguments.
Reviewed by: Matt Ahrens <mahrens@delphix.com>
Approved by: Robert Mustacchi <rm@joyent.com>
Author: Andriy Gapon <avg@FreeBSD.org>
https://www.illumos.org/issues/7600
At present, the kernel side code seems to blindly rollback to whatever happens
to be the latest snapshot at the time when the rollback task is processed.
The expected target's name should be passed to the kernel driver and the sync
task should validate that the target exists and that it is the latest snapshot
indeed.
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Reviewed by: Pavel Zakharov <pavel.zakharov@delphix.com>
Approved by: Robert Mustacchi <rm@joyent.com>
Author: Andriy Gapon <avg@FreeBSD.org>
https://www.illumos.org/issues/8377
The problem is that when dsl_bookmark_destroy_check() is executed from open
context (the pre-check), it fills in dbda_success based on the existence of the
bookmark.
But the bookmark (or containing filesystem as in this case) can be destroyed
before we get to syncing context. When we re-run dsl_bookmark_destroy_check()
in syncing
context, it will not add the deleted bookmark to dbda_success, intending for
dsl_bookmark_destroy_sync() to not process it. But because the bookmark is
still in dbda_success
from the open-context call, we do try to destroy it.
The fix is that dsl_bookmark_destroy_check() should not modify dbda_success
when called from open context.
Reviewed by: Paul Dagnelie <pcd@delphix.com>
Reviewed by: Pavel Zakharov <pavel.zakharov@delphix.com>
Reviewed by: George Wilson <george.wilson@delphix.com>
Approved by: Robert Mustacchi <rm@joyent.com>
Author: Matthew Ahrens <mahrens@delphix.com>
https://www.illumos.org/issues/8378
The problem is that zfs_get_data() supplies a stale zgd_bp to dmu_sync(), which
we then nopwrite against.
zfs_get_data() doesn't hold any DMU-related locks, so after it copies db_blkptr
to zgd_bp, dbuf_write_ready()
could change db_blkptr, and dbuf_write_done() could remove the dirty record.
dmu_sync() then sees the stale
BP and that the dbuf it not dirty, so it is eligible for nop-writing.
The fix is for dmu_sync() to copy db_blkptr to zgd_bp after acquiring the
db_mtx. We could still see a stale
db_blkptr, but if it is stale then the dirty record will still exist and thus
we won't attempt to nopwrite.
Reviewed by: Prakash Surya <prakash.surya@delphix.com>
Reviewed by: George Wilson <george.wilson@delphix.com>
Approved by: Robert Mustacchi <rm@joyent.com>
Author: Matthew Ahrens <mahrens@delphix.com>
https://www.illumos.org/issues/7910
It seems that the change in issue #6950 resurrected the problem that was
earlier fixed by the change in issue #5219.
Please also see the following FreeBSD bug report: https://bugs.freebsd.org/
bugzilla/show_bug.cgi?id=216178
Reviewed by: George Wilson <george.wilson@delphix.com>
Reviewed by: Dan Kimmel <dan.kimmel@delphix.com>
Approved by: Robert Mustacchi <rm@joyent.com>
Author: Andriy Gapon <avg@FreeBSD.org>
https://www.illumos.org/issues/8416
A C++ compiler fails to compile abd_is_linear(), which is an inline function
defined in abd.h, with the following error:
error: cannot initialize return object of type 'boolean_t' with an
rvalue of type 'bool'
That happens because a bool can not be converted to an enum in C++.
That's a problem because abd.h can be visible through other header files that a
C++ program that works with ZFS can include.
Reviewed by: Igor Kozhukhov <igor@dilos.org>
Reviewed by: Dan Kimmel <dan.kimmel@delphix.com>
Reviewed by: Alek Pinchuk <pinchuk.alek@gmail.com>
Approved by: Robert Mustacchi <rm@joyent.com>
Author: Andriy Gapon <avg@FreeBSD.org>
https://www.illumos.org/issues/8418
The following line in zfs_validate_name() is just a no-op and it should be
removed:
108 (void) zfs_prop_get_table();
https://www.illumos.org/issues/8311
Description:
There was a misunderstanding about the enforcement details of the "Read-only"
flag introduced for SMB/CIFS compatibility, way back in 2007 in the Sun PSARC
2007/315 case.
The original authors thought enforcement of the READONLY flag should work
similarly as the IMMUTABLE flag. Unfortunately, that enforcement is
incompatible with the expectations of Windows applications using this feature
through the SMB service. Applications assume (and the MS File System Algorithms
MS-FSA confirms they should) that an SMB client can:
(a) Open an SMB handle on a file with read/write access,
(b) Set the DOS attributes to include the READONLY flag,
(c) continue to have write access via that handle.
This access model is essentially the same as a Unix/POSIX application that
creates a file (with read/write access), uses fchmod() to change the file mode
to something not granting write access (i.e. 0444), and then continues to write
that file using the open handle it got before the mode change.
Currently, the SMB server works-around this problem in a way that will become
difficult to maintain as we implement support for SMB3 persistent handles, so
SMB depends on this fix.
I've written a test program that can be used to demonstrate this problem, and
added it to zfs-tests (tests/functional/acl/cifs/cifs_attr_004_pos).
It currently fails, but will pass when this problem fixed.
Steps to Reproduce:
Run the test program on a ZFS file system.
Expected Results:
Pass
Actual Results:
Fail.
Reviewed by: Sanjay Nadkarni <sanjay.nadkarni@nexenta.com>
Reviewed by: Yuri Pankov <yuri.pankov@nexenta.com>
Reviewed by: Andrew Stormont <andyjstormont@gmail.com>
Reviewed by: Matt Ahrens <mahrens@delphix.com>
Reviewed by: John Kennedy <john.kennedy@delphix.com>
Approved by: Prakash Surya <prakash.surya@delphix.com>
Author: Gordon Ross <gwr@nexenta.com>
https://www.illumos.org/issues/5220
There are disk devices that have logical sector size larger than 512B, for
example 4KB. That is, their physical sector size is larger than 512B and they
do not provide emulation for 512B sector sizes. For such devices both a data
offset and a data size must be properly aligned. L2ARC should arrange that
because it uses physical I/O.
zio_vdev_io_start() performs a necessary transformation if io_size is not
aligned to vdev_ashift, but that is done only for logical I/O. Something
similar should be done in L2ARC code.
* a temporary write buffer should be allocated if the original buffer is
not going to be compressed and its size is not aligned
* size of a temporary compression buffer should be ashift aligned
* for the reads, if a size of a target buffer is not sufficiently large and
it is not aligned then a temporary read buffer should be allocated
Reviewed by: George Wilson <george.wilson@delphix.com>
Reviewed by: Dan Kimmel <dan.kimmel@delphix.com>
Reviewed by: Saso Kiselkov <saso.kiselkov@nexenta.com>
Approved by: Dan McDonald <danmcd@joyent.com>
Author: Andriy Gapon <avg@FreeBSD.org>
projects / FreeBSD / FreeBSD.git / log