Commit Graph

4213 Commits

Author SHA1 Message Date
Alexander Motin 2cb992a99c
ZIL: Fix config lock deadlock.
When we have some LWBs closed and their ZIOs ready to be issued, we
can not afford sleeping on config lock if somebody else try to lock
it as writer, or it will cause a deadlock.

To solve it, move spa_config_enter() from zil_lwb_write_issue() to
zil_lwb_write_close() under zl_issuer_lock to enforce lock ordering
with other threads.  Now if we can't immediately lock config, issue
all previously closed LWBs so that they could drop their config
locks after completion, and only then allow sleeping on our lock.

Reviewed-by: Mark Maybee <mark.maybee@delphix.com>
Reviewed-by: Prakash Surya <prakash.surya@delphix.com>
Reviewed-by: George Wilson <george.wilson@delphix.com>
Signed-off-by: Alexander Motin <mav@FreeBSD.org>
Sponsored by: iXsystems, Inc.
Closes #15078
Closes #15080
2023-07-24 13:41:11 -07:00
Rob N 46adb2820a
metaslab: tuneable to better control force ganging
metaslab_force_ganging isn't enough to actually force ganging, because
it still only forces 3% of the time. This adds
metaslab_force_ganging_pct so we can configure how often to force
ganging.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Rob Norris <rob.norris@klarasystems.com>
Sponsored-by: Klara, Inc.
Sponsored-by: Wasabi Technology, Inc.
Closes #15088
2023-07-21 11:52:32 -07:00
Alexander Motin 34b3d498a9
Adjust prefetch parameters.
- Reduce maximum prefetch distance for 32bit platforms to 8MB as it
was previously.  Those systems didn't grow much probably, so better
stay conservative there.
 - Retire array_rd_sz tunable, blocking prefetch for large requests.
We should not penalize applications trying to be more efficient. The
speculative prefetcher by itself has reasonable distance limits, and
1MB is not much at all these days.

Reviewed-by: Allan Jude <allan@klarasystems.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by:	Alexander Motin <mav@FreeBSD.org>
Sponsored by:	iXsystems, Inc.
Closes #15072
2023-07-21 11:51:47 -07:00
Alexander Motin 28430b51e3
Add explicit prefetches to bpobj_iterate().
To simplify error handling bpobj_iterate_blkptrs() iterates through
the list of block pointers backwards.  Unfortunately speculative
prefetcher is currently unable to detect such patterns, that makes
each block read there synchronous and very slow on HDD pools.

According to my tests, added explicit prefetch reduces time needed
to asynchronously delete 8 snapshots of 4 million blocks each from
20 seconds to less than one, that should free sync thread for other
useful work, such as async writes, scrub, etc.

While there, plug one memory leak in case of bpobj_open() error and
harmonize some variable names.

Reviewed-by: Allan Jude <allan@klarasystems.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by:	Alexander Motin <mav@FreeBSD.org>
Sponsored by:	iXsystems, Inc.
Closes #15071
2023-07-21 11:50:48 -07:00
Alan Somers 6fd87e1d8d Don't emit cksum_{actual_expected} in ereport.fs.zfs.checksum events
With anything but fletcher-4, even a tiny change in the input will cause
the checksum value to change completely.  So knowing the actual and
expected checksums doesn't provide much more information than "they
don't match".  The harm in sending them is simply that they bloat the
event.  In particular, on FreeBSD the event must fit into a 1016 byte
buffer.

Fixes #14717 for mirrored pools.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Rich Ercolani <rincebrain@gmail.com>
Signed-off-by: Alan Somers <asomers@gmail.com>
Sponsored-by: Axcient
Closes #14717
Closes #15052
2023-07-21 11:49:26 -07:00
Alan Somers cf2a225b24 Don't emit checksum histograms in ereport.fs.zfs.checksum events
The checksum histograms were intended to be used with ATA and parallel
SCSI, which are obsolete.  With modern storage hardware, they will
almost always look like white noise; all bits will be wrong.  They only
serve to bloat the event.  That's a particular problem on FreeBSD, where
events must fit into a 1016 byte buffer.

This fixes issue #14717 for RAIDZ pools, but not for mirror pools.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Rich Ercolani <rincebrain@gmail.com>
Signed-off-by: Alan Somers <asomers@gmail.com>
Sponsored-by: Axcient
Closes #15052
2023-07-21 11:48:17 -07:00
Chunwei Chen 2d8a2b51dc
Fix zpl_test_super race with zfs_umount
We cannot call zpl_enter in zpl_test_super, because zpl_test_super is
under spinlock so we can't sleep, and also because zpl_test_super is
called without sb->s_umount taken, so it's possible we would race with
zfs_umount and call zpl_enter on freed zfsvfs.

Here's an stack trace when this happens:
[ 2379.114837] VERIFY(cvp->cv_magic == CV_MAGIC) failed
[ 2379.114845] PANIC at spl-condvar.c:497:__cv_broadcast()
[ 2379.114854] Kernel panic - not syncing: VERIFY(cvp->cv_magic == CV_MAGIC) failed
[ 2379.115012] Call Trace:
[ 2379.115019]  dump_stack+0x74/0x96
[ 2379.115024]  panic+0x114/0x2f6
[ 2379.115035]  spl_panic+0xcf/0xfc [spl]
[ 2379.115477]  __cv_broadcast+0x68/0xa0 [spl]
[ 2379.115585]  rrw_exit+0xb8/0x310 [zfs]
[ 2379.115696]  rrm_exit+0x4a/0x80 [zfs]
[ 2379.115808]  zpl_test_super+0xa9/0xd0 [zfs]
[ 2379.115920]  sget+0xd1/0x230
[ 2379.116033]  zpl_mount+0xdc/0x230 [zfs]
[ 2379.116037]  legacy_get_tree+0x28/0x50
[ 2379.116039]  vfs_get_tree+0x27/0xc0
[ 2379.116045]  path_mount+0x2fe/0xa70
[ 2379.116048]  do_mount+0x80/0xa0
[ 2379.116050]  __x64_sys_mount+0x8b/0xe0
[ 2379.116052]  do_syscall_64+0x35/0x50
[ 2379.116054]  entry_SYSCALL_64_after_hwframe+0x61/0xc6
[ 2379.116057] RIP: 0033:0x7f9912e8b26a

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Chunwei Chen <david.chen@nutanix.com>
Closes #15077
2023-07-20 10:30:21 -07:00
Ameer Hamza d9bb583c25
spa_min_alloc should be GCD, not min
Since spa_min_alloc may not be a power of 2, unlike ashifts, in the
case of DRAID, we should not select the minimal value among several
vdevs. Rounding to a multiple of it is unlikely to work for other
vdevs. Instead, using the greatest common divisor produces smaller
yet more reasonable results.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Signed-off-by: Ameer Hamza <ahamza@ixsystems.com>
Closes #15067
2023-07-20 10:23:52 -07:00
Yuri Pankov 929173ab42
Don't panic if setting vdev properties is unsupported for this vdev type
Check that vdev has valid zap and bail out early.

While here, move objid selection out of the loop, it's not going to
change.

Reviewed-by: Allan Jude <allan@klarasystems.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Yuri Pankov <yuripv@FreeBSD.org>
Closes #15063
2023-07-20 10:21:47 -07:00
Ameer Hamza 4d2dad04aa
Ignore pool ashift property during vdev attachment
Ashift can be set for a vdev only during its creation, and the
top-level vdev does not change when a vdev is attached or replaced.
The ashift property should not be used during attachment, as it
does not allow attaching/replacing a vdev if the pool's ashift
property is increased after the existing vdev was created. Instead,
we should be able to attach the vdev if the attached vdev can
satisfy the ashift requirement with its parent.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Signed-off-by: Ameer Hamza <ahamza@ixsystems.com>
Closes #15061
2023-07-20 09:57:16 -07:00
Alexander Motin 7d0df5422c
Do not request data L1 buffers on scan prefetch.
Set ARC_FLAG_NO_BUF when prefetching data L1 buffers for scan.  We
do not prefetch data L0 buffers, so we do not need the L1 buffers,
only want them to be ready in ARC. This saves some CPU time on the
buffers decompression.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by:	Alexander Motin <mav@FreeBSD.org>
Sponsored by:	iXsystems, Inc.
Closes #15029
2023-07-20 09:10:04 -07:00
Yuri Pankov 8beabfd3bf
set autotrim default to 'off' everywhere
As it turns out having autotrim default to 'on' on FreeBSD never really
worked due to mess with defines where userland and kernel module were
getting different default values (userland was defaulting to 'off',
module was thinking it's 'on').

Reviewed-by: Tino Reichardt <milky-zfs@mcmilk.de>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Signed-off-by: Yuri Pankov <yuripv@FreeBSD.org>
Closes #15079
2023-07-20 09:06:55 -07:00
Alexander Motin c4e8742149
Fix raw receive with different indirect block size.
Unlike regular receive, raw receive require destination to have the
same block structure as the source.  In case of dnode reclaim this
triggers two special cases, requiring special handling:
 - If dn_nlevels == 1, we can change the ibs, but dnode_set_blksz()
should not dirty the data buffer if block size does not change, or
durign receive dbuf_dirty_lightweight() will trigger assertion.
 - If dn_nlevels > 1, we just can't change the ibs, dnode_set_blksz()
would fail and receive_object would trigger assertion, so we should
destroy and recreate the dnode from scratch.

Reviewed-by: Paul Dagnelie <pcd@delphix.com>
Signed-off-by:	Alexander Motin <mav@FreeBSD.org>
Sponsored by:	iXsystems, Inc.
Closes #15039
2023-07-14 16:16:40 -07:00
Alan Somers 67c5e1ba4f
Fix the ZFS checksum error histograms with larger record sizes
My analysis in PR #14716 was incorrect.  Each histogram bucket contains
the number of incorrect bits, by position in a 64-bit word, over the
entire record.  8-bit buckets can overflow for record sizes above 2k.
To forestall that, saturate each bucket at 255.  That should still get
the point across: either all bits are equally wrong, or just a couple
are.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Alan Somers <asomers@gmail.com>
Sponsored-by: Axcient
Closes #15049
2023-07-14 16:13:15 -07:00
Alexander Motin fdba8cbb79
Avoid extra snprintf() in dsl_deadlist_merge().
Since we are already iterating the ZAP, we have exact string key to
remove, we do not need to call zap_remove_int() with the int key we
just converted, we can call zap_remove() for the original string.

This should make no functional change, only a micro-optimization.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by:	Alexander Motin <mav@FreeBSD.org>
Sponsored by:	iXsystems, Inc.
Closes #15056
2023-07-14 16:11:46 -07:00
Alexander Motin 6db781d52c
Add missed DMU_PROJECTUSED_OBJECT prefetch.
It seems 9c5167d19f "Project Quota on ZFS" missed to add prefetch
for DMU_PROJECTUSED_OBJECT during scan (scrub/resilver).  It should
not cause visible problems, but may affect scub/resilver performance.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by:	Alexander Motin <mav@FreeBSD.org>
Sponsored by:	iXsystems, Inc.
Closes #15024
2023-07-13 09:12:55 -07:00
Alexander Motin 736d5962b4
FreeBSD: Fix build on stable/13 after 1302506.
Starting approximately from version 1302506 vn_lock_pair() grown two
additional arguments following head.  There is a one week hole, but
that is closet reference point we have.

Reviewed-by: Mateusz Guzik <mjguzik@gmail.com>
Signed-off-by:  Alexander Motin <mav@FreeBSD.org>
Sponsored by:   iXsystems, Inc.
Closes #15047
2023-07-13 08:50:34 -07:00
Prakash Surya 945e39fc3a
Enable tuning of ZVOL open timeout value
The default timeout for ZVOL opens may not be sufficient for all cases,
so we should enable the value to be more easily tuned to account for
systems where the default value is insufficient.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Reviewed-by: Matthew Ahrens <mahrens@delphix.com>
Signed-off-by: Prakash Surya <prakash.surya@delphix.com>
Closes #15023
2023-06-30 11:34:05 -07:00
Rich Ercolani 2b10e32561
Pack our DDT ZAPs a bit denser.
The DDT is really inefficient on 4k and up vdevs, because it always
allocates 4k blocks, and while compression could save us somewhat
at ashift 9, that stops being true.

So let's change the default to 32 KiB, which seems like a reasonable
compromise between improved space savings and inflated write sizes
for DDT updates.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Rich Ercolani <rincebrain@gmail.com>
Closes #14654
2023-06-30 09:42:02 -07:00
Rob N 61ab05cac7
ddt_addref: remove unnecessary phys fill when refcount is 0
The previous comment wondered if this case could happen; it turns out
that it really can't.

This block can only be entered if dde_type and dde_class are "real";
that only happens when a ddt entry has been previously synced to a ddt
store, that is, it was created on a previous txg. Since its gone through
that sync, its dde_refcount must be >0.

ddt_addref() is called from brt_pending_apply(), which is called at the
beginning of spa_sync(), before pending DMU writes/frees are issued.
Freeing a dedup block is the only thing that can decrement dde_refcount,
so there's no way for it to drop to zero before applying the clone bumps
it.

Further, even if it _could_ go to zero, it wouldn't be necessary to fill
the entry from the block. The phys content is not cleared until the free
is issued, which happens when the refcount goes to zero, when the last
real free comes through. The cloned block should be identical to what's
in the phys already, so the fill should be a no-op anyway.

I've replaced this with an assertion because this is all very dependent
on the ordering in which BRT and DDT changes are applied, and that might
change in the future.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Rob Norris <rob.norris@klarasystems.com>
Sponsored-By: Klara, Inc.
Closes #15004
2023-06-30 09:01:58 -07:00
Alexander Motin 233425a153
Again fix race between zil_commit() and zil_suspend().
With zl_suspend read in zil_commit() not protected by any locks it
is possible for new ZIL writes to be in progress while zil_destroy()
called by zil_suspend() freeing them.  This patch closes the race
by taking zl_issuer_lock in zil_suspend() and adding the second
zl_suspend check to zil_get_commit_list(), protected by the lock.
It allows all already queued transactions to be logged normally,
while blocks any new ones, calling txg_wait_synced() for the TXGs.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by:	Alexander Motin <mav@FreeBSD.org>
Sponsored by:	iXsystems, Inc.
Closes #14979
2023-06-30 08:59:39 -07:00
Alexander Motin b4a0873092
Some ZIO micro-optimizations.
- Pack struct zio_prop by 4 bytes from 84 to 80.
 - Skip new child ZIO locking while linking to parent.  The newly
allocated ZIO is not externally visible yet, so nobody should care.
 - Skip io_bp_copy writes when not used (write && non-debug).

Reviewed-by: Brian Atkinson <batkinson@lanl.gov>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by:	Alexander Motin <mav@FreeBSD.org>
Sponsored by:	iXsystems, Inc.
Closes #14985
2023-06-30 08:54:00 -07:00
Alexander Motin fa7b2390d4
Do not report bytes skipped by scan as issued.
Scan process may skip blocks based on their birth time, DVA, etc.
Traditionally those blocks were accounted as issued, that caused
reporting of hugely over-inflated numbers, having nothing to do
with actual disk I/O.  This change utilizes never used field in
struct dsl_scan_phys to account such skipped bytes, allowing to
report how much data were actually scrubbed/resilvered and what
is the actual I/O speed.  While formally it is an on-disk format
change, it should be compatible both ways, so should not need a
feature flag.

This should partially address the same issue as c85ac731a0, but
from a different perspective, complementing it.

Reviewed-by: Tony Hutter <hutter2@llnl.gov>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Akash B <akash-b@hpe.com>
Signed-off-by:  Alexander Motin <mav@FreeBSD.org>
Sponsored by:   iXsystems, Inc.
Closes #15007
2023-06-30 08:47:13 -07:00
Alexander Motin a9d6b0690b
ZIL: Fix another use-after-free.
lwb->lwb_issued_txg can not be accessed after lwb_state is set to
LWB_STATE_FLUSH_DONE and zl_lock is dropped, since the lwb may be
freed by zil_sync().  We must save the txg number before that.

This is similar to the 55b1842f92, but as I see the bug is not new.
It existed for quite a while, just was not triggered due to smaller
race window.

Reviewed-by: Allan Jude <allan@klarasystems.com>
Reviewed-by: Brian Atkinson <batkinson@lanl.gov>
Signed-off-by:	Alexander Motin <mav@FreeBSD.org>
Sponsored by:	iXsystems, Inc.
Closes #14988
Closes #14999
2023-06-27 17:03:37 -07:00
Alexander Motin b0cbc1aa9a
Use big transactions for small recordsize writes.
When ZFS appends files in chunks bigger than recordsize, it borrows
buffer from ARC and fills it before opening transaction.  This
supposed to help in case of page faults to not hold transaction open
indefinitely.  The problem appears when recordsize is set lower than
default 128KB. Since each block is committed in separate transaction,
per-transaction overhead becomes significant, and what is even worse,
active use of of per-dataset and per-pool locks to protect space use
accounting for each transaction badly hurts the code SMP scalability.
The same transaction size limitation applies in case of file rewrite,
but without even excuse of buffer borrowing.

To address the issue, disable the borrowing mechanism if recordsize
is smaller than default and the write request is 4x bigger than it.
In such case writes up to 32MB are executed in single transaction,
that dramatically reduces overhead and lock contention.  Since the
borrowing mechanism is not used for file rewrites, and it was never
used by zvols, which seem to work fine, I don't think this change
should create significant problems, partially because in addition to
the borrowing mechanism there are also used pre-faults.

My tests with 4/8 threads writing several files same time on datasets
with 32KB recordsize in 1MB requests show reduction of CPU usage by
the user threads by 25-35%.  I would measure it in GB/s, but at that
block size we are now limited by the lock contention of single write
issue taskqueue, which is a separate problem we are going to work on.

Reviewed-by: Brian Atkinson <batkinson@lanl.gov>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by:	Alexander Motin <mav@FreeBSD.org>
Sponsored by:	iXsystems, Inc.
Closes #14964
2023-06-27 17:00:30 -07:00
Alexander Motin 8469b5aac0
Another set of vdev queue optimizations.
Switch FIFO queues (SYNC/TRIM) and active queue of vdev queue from
time-sorted AVL-trees to simple lists.  AVL-trees are too expensive
for such a simple task.  To change I/O priority without searching
through the trees, add io_queue_state field to struct zio.

To not check number of queued I/Os for each priority add vq_cqueued
bitmap to struct vdev_queue.  Update it when adding/removing I/Os.
Make vq_cactive a separate array instead of struct vdev_queue_class
member.  Together those allow to avoid lots of cache misses when
looking for work in vdev_queue_class_to_issue().

Introduce deadline of ~0.5s for LBA-sorted queues.  Before this I
saw some I/Os waiting in a queue for up to 8 seconds and possibly
more due to starvation.  With this change I no longer see it.  I
had to slightly more complicate the comparison function, but since
it uses all the same cache lines the difference is minimal.  For a
sequential I/Os the new code in vdev_queue_io_to_issue() actually
often uses more simple avl_first(), falling back to avl_find() and
avl_nearest() only when needed.

Arrange members in struct zio to access only one cache line when
searching through vdev queues.  While there, remove io_alloc_node,
reusing the io_queue_node instead.  Those two are never used same
time.

Remove zfs_vdev_aggregate_trim parameter.  It was disabled for 4
years since implemented, while still wasted time maintaining the
offset-sorted tree of TRIM requests.  Just remove the tree.

Remove locking from txg_all_lists_empty().  It is racy by design,
while 2 pair of locks/unlocks take noticeable time under the vdev
queue lock.

With these changes in my tests with volblocksize=4KB I measure vdev
queue lock spin time reduction by 50% on read and 75% on write.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by:	Alexander Motin <mav@FreeBSD.org>
Sponsored by:	iXsystems, Inc.
Closes #14925
2023-06-27 09:09:48 -07:00
Rich Ercolani 35a6247c5f
Add a delay to tearing down threads.
It's been observed that in certain workloads (zvol-related being a
big one), ZFS will end up spending a large amount of time spinning
up taskqs only to tear them down again almost immediately, then
spin them up again...

I noticed this when I looked at what my mostly-idle system was doing
and wondered how on earth taskq creation/destroy was a bunch of time...

So I added a configurable delay to avoid it tearing down tasks the
first time it notices them idle, and the total number of threads at
steady state went up, but the amount of time being burned just
tearing down/turning up new ones almost vanished.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Rich Ercolani <rincebrain@gmail.com>
Closes #14938
2023-06-26 13:57:12 -07:00
Alexander Motin 8e8acabdca
Fix memory leak in zil_parse().
482da24e2 missed arc_buf_destroy() calls on log parse errors, possibly
leaking up to 128KB of memory per dataset during ZIL replay.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Paul Dagnelie <pcd@delphix.com>
Signed-off-by:	Alexander Motin <mav@FreeBSD.org>
Sponsored by:	iXsystems, Inc.
Closes #14987
2023-06-17 19:51:37 -07:00
Alexander Motin ccec7fbe1c
Remove ARC/ZIO physdone callbacks.
Those callbacks were introduced many years ago as part of a bigger
patch to smoothen the write throttling within a txg. They allow to
account completion of individual physical writes within a logical
one, improving cases when some of physical writes complete much
sooner than others, gradually opening the write throttle.

Few years after that ZFS got allocation throttling, working on a
level of logical writes and limiting number of writes queued to
vdevs at any point, and so limiting latency distribution between
the physical writes and especially writes of multiple copies.
The addition of scheduling deadline I proposed in #14925 should
further reduce the latency distribution.  Grown memory sizes over
the past 10 years should also reduce importance of the smoothing.

While the use of physdone callback may still in theory provide
some smoother throttling, there are cases where we simply can not
afford it.  Since dirty data accounting is protected by pool-wide
lock, in case of 6-wide RAIDZ, for example, it requires us to take
it 8 times per logical block write, creating huge lock contention.

My tests of this patch show radical reduction of the lock spinning
time on workloads when smaller blocks are written to RAIDZ pools,
when each of the disks receives 8-16KB chunks, but the total rate
reaching 100K+ blocks per second.  Same time attempts to measure
any write time fluctuations didn't show anything noticeable.

While there, remove also io_child_count/io_parent_count counters.
They are used only for couple assertions that can be avoided.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Alexander Motin <mav@FreeBSD.org>
Sponsored by:	iXsystems, Inc.
Closes #14948
2023-06-15 10:49:03 -07:00
Alexander Motin d057807ede
Switch refcount tracking from lists to AVL-trees.
With large number of tracked references list searches under the lock
become too expensive, creating enormous lock contention.

On my tests with ZFS_DEBUG enabled this increases write throughput
with 32KB blocks from ~1.2GB/s to ~7.5GB/s.

Reviewed-by: Brian Atkinson <batkinson@lanl.gov>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Alexander Motin <mav@FreeBSD.org>
Sponsored by:	iXsystems, Inc.
Closes #14970
2023-06-14 08:02:27 -07:00
George Amanakis 8af1104f83
Store the L2ARC device ashift in the vdev label
If this is not done, and the pool has an ashift other than the default
(at the moment 9) then the following happens:

1) vdev_alloc() assigns the ashift of the pool to L2ARC device, but
   upon export it is not stored anywhere
2) at the first import, vdev_open() sees an vdev_ashift() of 0 and
   assigns the logical_ashift, which is 9
3) reading the contents of L2ARC, including the header fails
4) L2ARC buffers are not restored in ARC.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: George Amanakis <gamanakis@gmail.com>
Closes #14313 
Closes #14963
2023-06-14 08:01:17 -07:00
George Amanakis feff9dfed3
Fix the L2ARC write size calculating logic (2)
While commit bcd5321 adjusts the write size based on the size of the log
block, this happens after comparing the unadjusted write size to the
evicted (target) size.

In this case l2ad_hand will exceed l2ad_evict and violate an assertion
at the end of l2arc_write_buffers().

Fix this by adding the max log block size to the allocated size of the
buffer to be committed before comparing the result to the target
size.

Also reset the l2arc_trim_ahead ZFS module variable when the adjusted
write size exceeds the size of the L2ARC device.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: George Amanakis <gamanakis@gmail.com>
Closes #14936
Closes #14954
2023-06-09 17:05:47 -07:00
Alexander Motin 70ea484e3e
Finally drop long disabled vdev cache.
It was a vdev level read cache, designed to aggregate many small
reads by speculatively issuing bigger reads instead and caching
the result.  But since it has almost no idea about what is going
on with exception of ZIO_FLAG_DONT_CACHE flag set by higher layers,
it was found to make more harm than good, for which reason it was
disabled for the past 12 years.  These days we have much better
instruments to enlarge the I/Os, such as speculative and prescient
prefetches, I/O scheduler, I/O aggregation etc.

Besides just the dead code removal this removes one extra mutex
lock/unlock per write inside vdev_cache_write(), not otherwise
disabled and trying to do some work.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by:	Alexander Motin <mav@FreeBSD.org>
Sponsored by:	iXsystems, Inc.
Closes #14953
2023-06-09 12:40:55 -07:00
Alexander Motin b3ad3f48d9
Use list_remove_head() where possible.
... instead of list_head() + list_remove().  On FreeBSD the list
functions are not inlined, so in addition to more compact code
this also saves another function call.

Reviewed-by: Brian Atkinson <batkinson@lanl.gov>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by:	Alexander Motin <mav@FreeBSD.org>
Sponsored by:	iXsystems, Inc.
Closes #14955
2023-06-09 10:12:52 -07:00
Alexander Motin 55b1842f92
ZIL: Fix race introduced by f63811f072.
We are not allowed to access lwb after setting LWB_STATE_FLUSH_DONE
state and dropping zl_lock, since it may be freed by zil_sync().
To free itxs and waiters after dropping the lock we need to move
lwb_itxs and lwb_waiters lists elements to local storage.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by:	Alexander Motin <mav@FreeBSD.org>
Sponsored by:	iXsystems, Inc.
Closes #14957
Closes #14959
2023-06-09 10:08:05 -07:00
Brian Behlendorf 93f8abeff0
Linux: Never sleep in kmem_cache_alloc(..., KM_NOSLEEP) (#14926)
When a kmem cache is exhausted and needs to be expanded a new
slab is allocated.  KM_SLEEP callers can block and wait for the
allocation, but KM_NOSLEEP callers were incorrectly allowed to
block as well.

Resolve this by attempting an emergency allocation as a best
effort.  This may fail but that's fine since any KM_NOSLEEP
consumer is required to handle an allocation failure.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Adam Moss <c@yotes.com>
Reviewed-by: Brian Atkinson <batkinson@lanl.gov>
Reviewed-by: Richard Yao <richard.yao@alumni.stonybrook.edu>
Reviewed-by: Tony Hutter <hutter2@llnl.gov>
2023-06-07 10:43:43 -07:00
George Amanakis bcd5321039
Fix the L2ARC write size calculating logic
l2arc_write_size() should return the write size after adjusting for trim
and overhead of the L2ARC log blocks. Also take into account the
allocated size of log blocks when deciding when to stop writing buffers
to L2ARC.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: George Amanakis <gamanakis@gmail.com>
Closes #14939
2023-06-06 12:32:37 -07:00
Rob Norris 8653f1de48 zdb: add -B option to generate backup stream
This is more-or-less like `zfs send`, but specifying the snapshot by its
objset id for situations where it can't be referenced any other way.

Sponsored-By: Klara, Inc.
Reviewed-by: Tino Reichardt <milky-zfs@mcmilk.de>
Reviewed-by: WHR <msl0000023508@gmail.com>
Signed-off-by: Rob Norris <rob.norris@klarasystems.com>
Closes #14642
2023-06-05 11:54:42 -07:00
Rob Norris 2b9f8ba673 znode: expose zfs_get_zplprop to libzpool
There's no particular reason this function should be kernel-only, and I
want to use it (indirectly) from zdb. I've moved it to zfs_znode.c
because libzpool does not compile in zfs_vfsops.c, and this at least
matches the header its imported from.

Sponsored-By: Klara, Inc.
Reviewed-by: Tino Reichardt <milky-zfs@mcmilk.de>
Reviewed-by: WHR <msl0000023508@gmail.com>
Signed-off-by: Rob Norris <rob.norris@klarasystems.com>
Closes #14642
2023-06-05 11:53:44 -07:00
Alexander Motin 5ba4025a8d
Introduce zfs_refcount_(add|remove)_few().
There are two places where we need to add/remove several references
with semantics of zfs_refcount_(add|remove). But when debug/tracing
is disabled, it is a crime to run multiple atomic_inc() in a loop,
especially under congested pool-wide allocator lock.

Introduced new functions implement the same semantics as the loop,
but without overhead in production builds.

Reviewed-by: Rich Ercolani <rincebrain@gmail.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by:	Alexander Motin <mav@FreeBSD.org>
Sponsored by:	iXsystems, Inc.
Closes #14934
2023-06-05 11:51:44 -07:00
Alexander Motin 482da24e20
ZIL: Allow to replay blocks of any size.
There seems to be no reason for ZIL blocks to be limited by 128KB
other than replay code is written in such a way.  This change does
not increase the limit yet, just removes the artificial limitation.

Avoided extra memcpy() may save us a second during replay.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Prakash Surya <prakash.surya@delphix.com>
Signed-off-by:	Alexander Motin <mav@FreeBSD.org>
Sponsored by:	iXsystems, Inc.
Closes #14910
2023-06-02 11:01:58 -07:00
Luís Henriques 928c81f4df
Fix NULL pointer dereference when doing concurrent 'send' operations
A NULL pointer will occur when doing a 'zfs send -S' on a dataset that
is still being received.  The problem is that the new 'send' will
rightfully fail to own the datasets (i.e. dsl_dataset_own_force() will
fail), but then dmu_send() will still do the dsl_dataset_disown().

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Luís Henriques <henrix@camandro.org>
Closes #14903 
Closes #14890
2023-05-30 15:15:24 -07:00
Richard Yao 677c6f8457
btree: Implement faster binary search algorithm
This implements a binary search algorithm for B-Trees that reduces
branching to the absolute minimum necessary for a binary search
algorithm. It also enables the compiler to inline the comparator to
ensure that the only slowdown when doing binary search is from waiting
for memory accesses. Additionally, it instructs the compiler to unroll
the loop, which gives an additional 40% improve with Clang and 8%
improvement with GCC.

Consumers must opt into using the faster algorithm. At present, only
B-Trees used inside kernel code have been modified to use the faster
algorithm.

Micro-benchmarks suggest that this can improve binary search performance
by up to 3.5 times when compiling with Clang 16 and up to 1.9 times when
compiling with GCC 12.2.

Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Richard Yao <richard.yao@alumni.stonybrook.edu>
Closes #14866
2023-05-26 10:03:12 -07:00
George Amanakis bb736d98d1
Fix inconsistent definition of zfs_scrub_error_blocks_per_txg
Reviewed-by: Richard Yao <richard.yao@alumni.stonybrook.edu>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: George Amanakis <gamanakis@gmail.com>
Closes #14894
2023-05-26 09:53:00 -07:00
Alexander Motin b6fbe61fa6
zil: Add some more statistics.
In addition to a number of actual log bytes written, account also a
total written bytes including padding and total allocated bytes (bytes
<= write <= alloc).  It should allow to monitor zil traffic and space
efficiency.

Add dtrace probe for zil block size selection.

Make zilstat report more information and fit it into less width.

Reviewed-by: Ameer Hamza <ahamza@ixsystems.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by:  Alexander Motin <mav@FreeBSD.org>
Sponsored by:   iXsystems, Inc.
Closes #14863
2023-05-25 13:51:53 -07:00
Alexander Motin f63811f072
ZIL: Reduce scope of per-dataset zl_issuer_lock.
Before this change ZIL copied all log data while holding the lock.
It caused huge lock contention on workloads with many big parallel
writes.  This change splits the process into two parts: first,
zil_lwb_assign() estimates the log space needed for all transactions,
and zil_lwb_write_close() allocates blocks and zios while holding the
lock, then, after the lock in dropped, zil_lwb_commit() copies the
data, and zil_lwb_write_issue() issues the I/Os.

Also while there slightly reduce scope of zl_lock.

Reviewed-by: Paul Dagnelie <pcd@delphix.com>
Reviewed-by: Prakash Surya <prakash.surya@delphix.com>
Reviewed-by: Richard Yao <richard.yao@alumni.stonybrook.edu>
Signed-off-by:  Alexander Motin <mav@FreeBSD.org>
Sponsored by:   iXsystems, Inc.
Closes #14841
2023-05-25 09:48:43 -07:00
Akash B 9d618615d1
Fix concurrent resilvers initiated at same time
For draid vdevs it was possible to initiate both the
sequential and healing resilver at same time.

This fixes the following two scenarios.
     1) There's a window where a sequential rebuild can
be started via ZED even if a healing resilver has been
scheduled.
	- This is fixed by adding additional check in
spa_vdev_attach() for any scheduled resilver and return
appropriate error code when a resilver is already in
progress.

     2) It was possible for zpool clear to start a healing
resilver when it wasn't needed at all. This occurs because
during a vdev_open() the device is presumed to be healthy not
until the device is validated by vdev_validate() and it's set
unavailable. However, by this point an async resilver will
have already been requested if the DTL isn't empty.
	- This is fixed by cancelling the SPA_ASYNC_RESILVER
request immediately at the end of vdev_reopen() when a resilver
is unneeded.

Finally, added a testcase in ZTS for verification.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Dipak Ghosh <dipak.ghosh@hpe.com>
Signed-off-by: Akash B <akash-b@hpe.com>
Closes #14881
Closes #14892
2023-05-24 12:28:09 -07:00
youzhongyang f8447cf22e
Linux 6.4 compat: reclaimed_slab renamed to reclaimed
Reviewed-by: Richard Yao <richard.yao@alumni.stonybrook.edu>
Reviewed-by: Brian Atkinson <batkinson@lanl.gov>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Youzhong Yang <yyang@mathworks.com>
Closes #14891
2023-05-24 12:23:42 -07:00
Brian Atkinson ad0a554614
Hold db_mtx when updating db_state
Commit 555ef90 did some general code refactoring for
dmu_buf_will_not_fill() and dmu_buf_will_fill(). However, the db_mtx was
not held when update db->db_state in those code block. The rest of the
dbuf code always holds the db_mtx when updating db_state. This is
important because cv_wait() db_changed is used to check for db_state
changes.

Updating dmu_buf_will_not_fill() and dmu_buf_will_fill() to hold the
db_mtx when updating db_state.

Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Brian Atkinson <batkinson@lanl.gov>
Closes #14875
2023-05-19 13:05:53 -07:00
Brian Behlendorf 577e835f30
Probe vdevs before marking removed
Before allowing the ZED to mark a vdev as REMOVED due to a
hotplug event confirm that it is non-responsive with probe.
Any device which can be successfully probed should be left
ONLINE to prevent a healthy pool from being incorrectly
SUSPENDED.  This may occur for at least the following two
scenarios.

1) Drive expansion (zpool online -e) in VMware environments.
   If, during the partition resize operation, a partition is
   removed and re-created then udev will send a removed event.

2) Re-scanning the namespaces of an NVMe device (nvme ns-rescan)
   may result in a udev remove and add event being delivered.

Finally, update the ZED to only kick in a spare when the
removal was successful.

Reviewed-by: Ameer Hamza <ahamza@ixsystems.com>
Reviewed-by: Tony Hutter <hutter2@llnl.gov>
Reviewed-by: Richard Yao <richard.yao@alumni.stonybrook.edu>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #14859
Closes #14861
2023-05-19 13:05:09 -07:00