= Problem
While examining a customer's system we noticed unreasonable space
usage from a few snapshots due to gang blocks. Under some further
analysis we discovered that the pool would create gang blocks because
all its disks had non-zero write error counts and they'd be skipped
for normal metaslab allocations due to the following if-clause in
`metaslab_alloc_dva()`:
```
/*
* Avoid writing single-copy data to a failing,
* non-redundant vdev, unless we've already tried all
* other vdevs.
*/
if ((vd->vdev_stat.vs_write_errors > 0 ||
vd->vdev_state < VDEV_STATE_HEALTHY) &&
d == 0 && !try_hard && vd->vdev_children == 0) {
metaslab_trace_add(zal, mg, NULL, psize, d,
TRACE_VDEV_ERROR, allocator);
goto next;
}
```
= Proposed Solution
Get rid of the predicate in the if-clause that checks the past
write errors of the selected vdev. We still try to allocate from
HEALTHY vdevs anyway by checking vdev_state so the past write
errors doesn't seem to help us (quite the opposite - it can cause
issues in long-lived pools like the one from our customer).
= Testing
I first created a pool with 3 vdevs:
```
$ zpool list -v volpool
NAME SIZE ALLOC FREE
volpool 22.5G 117M 22.4G
xvdb 7.99G 40.2M 7.46G
xvdc 7.99G 39.1M 7.46G
xvdd 7.99G 37.8M 7.46G
```
And used `zinject` like so with each one of them:
```
$ sudo zinject -d xvdb -e io -T write -f 0.1 volpool
```
And got the vdevs to the following state:
```
$ zpool status volpool
pool: volpool
state: ONLINE
status: One or more devices has experienced an unrecoverable error.
...<cropped>..
action: Determine if the device needs to be replaced, and clear the
...<cropped>..
config:
NAME STATE READ WRITE CKSUM
volpool ONLINE 0 0 0
xvdb ONLINE 0 1 0
xvdc ONLINE 0 1 0
xvdd ONLINE 0 4 0
```
I also double-checked their write error counters with sdb:
```
sdb> spa volpool | vdev | member vdev_stat.vs_write_errors
(uint64_t)0 # <---- this is the root vdev
(uint64_t)2
(uint64_t)1
(uint64_t)1
```
Then I checked that I the problem was reproduced in my VM as I the
gang count was growing in zdb as I was writting more data:
```
$ sudo zdb volpool | grep gang
ganged count: 1384
$ sudo zdb volpool | grep gang
ganged count: 1393
$ sudo zdb volpool | grep gang
ganged count: 1402
$ sudo zdb volpool | grep gang
ganged count: 1414
```
Then I updated my bits with this patch and the gang count stayed the
same.
Reviewed-by: Mark Maybee <mark.maybee@delphix.com>
Reviewed-by: Matthew Ahrens <mahrens@delphix.com>
Reviewed-by: Richard Yao <richard.yao@alumni.stonybrook.edu>
Signed-off-by: Serapheim Dimitropoulos <serapheim@delphix.com>
Closes#14003
= Issue
Recently we hit an assertion panic in `dsl_process_sub_livelist` while
exporting the spa and interrupting `bpobj_iterate_nofree`. In that case
`bpobj_iterate_nofree` stops mid-way returning an EINTR without clearing
the intermediate AVL tree that keeps track of the livelist entries it
has encountered so far. At that point the code has a VERIFY for the
number of elements of the AVL expecting it to be zero (which is not the
case for EINTR).
= Fix
Cleanup any intermediate state before destroying the AVL when
encountering EINTR. Also added a comment documenting the scenario where
the EINTR comes up. There is no need to do anything else for the calles
of `dsl_process_sub_livelist` as they already handle the EINTR case.
Reviewed-by: Matthew Ahrens <mahrens@delphix.com>
Reviewed-by: Mark Maybee <mark.maybee@delphix.com>
Reviewed-by: Richard Yao <richard.yao@alumni.stonybrook.edu>
Signed-off-by: Serapheim Dimitropoulos <serapheim@delphix.com>
Closes#13939
The current value causes significant artificial slowdown during mass
parallel file removal, which can be observed both on FreeBSD and Linux
when running real workloads.
Sample results from Linux doing make -j 96 clean after an allyesconfig
modules build:
before: 4.14s user 6.79s system 48% cpu 22.631 total
after: 4.17s user 6.44s system 153% cpu 6.927 total
FreeBSD results in the ticket.
Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Richard Yao <richard.yao@alumni.stonybrook.edu>
Reviewed-by: George Melikov <mail@gmelikov.ru>
Signed-off-by: Mateusz Guzik <mjguzik@gmail.com>
Closes#13932Closes#13938
Currently, additional/extra copies are created for metadata in
addition to the redundancy provided by the pool(mirror/raidz/draid),
due to this 2 times more space is utilized per inode and this decreases
the total number of inodes that can be created in the filesystem. By
setting redundant_metadata to none, no additional copies of metadata
are created, hence can reduce the space consumed by the additional
metadata copies and increase the total number of inodes that can be
created in the filesystem. Additionally, this can improve file create
performance due to the reduced amount of metadata which needs
to be written.
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#13680
- Add a zfs_exit() call in an error path, otherwise a lock is leaked.
- Remove the fid_gen > 1 check. That appears to be Linux-specific:
zfsctl_snapdir_fid() sets fid_gen to 0 or 1 depending on whether the
snapshot directory is mounted. On FreeBSD it fails, making snapshot
dirs inaccessible via NFS.
Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Reviewed-by: Ryan Moeller <ryan@iXsystems.com>
Reviewed-by: Andriy Gapon <avg@FreeBSD.org>
Signed-off-by: Mark Johnston <markj@FreeBSD.org>
Fixes: 43dbf88178 ("FreeBSD: vfsops: use setgen for error case")
Closes#14001Closes#13974
(cherry picked from commit ed566bf1cd)
This patch handles the race condition on simultaneous failure of
2 drives, which misses the vdev_rebuild_reset_wanted signal in
vdev_rebuild_thread. We retry to catch this inside the
vdev_rebuild_complete_sync function.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Richard Yao <richard.yao@alumni.stonybrook.edu>
Reviewed-by: Dipak Ghosh <dipak.ghosh@hpe.com>
Reviewed-by: Akash B <akash-b@hpe.com>
Signed-off-by: Samuel Wycliffe J <samwyc@hpe.com>
Closes#14041Closes#14050
This error occurred when building on Gentoo with debugging enabled:
zfs-kmod-2.1.6/work/zfs-2.1.6/module/icp/core/kcf_sched.c:1277:14:
error: a function declaration without a prototype is deprecated
in all versions of C [-Werror,-Wstrict-prototypes]
kcfpool_alloc()
^
void
1 error generated.
This function is not present in master.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Tony Hutter <hutter2@llnl.gov>
Signed-off-by: Richard Yao <richard.yao@alumni.stonybrook.edu>
Closes#14023
Clang's static analyzer found a bad free caused by skein_mac_atomic().
It will allocate a context on the stack and then pass it to
skein_final(), which attempts to free it. Upon inspection,
skein_digest_atomic() also has the same problem.
These functions were created to match the OpenSolaris ICP API, so I was
curious how we avoided this in other providers and looked at the SHA2
code. It appears that SHA2 has a SHA2Final() helper function that is
called by the exported sha2_mac_final()/sha2_digest_final() as well as
the sha2_mac_atomic() and sha2_digest_atomic() functions. The real work
is done in SHA2Final() while some checks and the free are done in
sha2_mac_final()/sha2_digest_final().
We fix the use after free in the skein code by taking inspiration from
the SHA2 code. We introduce a skein_final_nofree() that does most of the
work, and make skein_final() into a function that calls it and then
frees the memory.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Tony Hutter <hutter2@llnl.gov>
Signed-off-by: Richard Yao <richard.yao@alumni.stonybrook.edu>
Closes#13954
There is an ongoing effort to eliminate this feature.
Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Reviewed-by: Ryan Moeller <ryan@iXsystems.com>
Signed-off-by: Mateusz Guzik <mjguzik@gmail.com>
Closes#13908
When reviewing #13875, I noticed that our FreeBSD code has an issue
where it converts from `int64_t` to `int` when calling
`vnlru_free{,_vfsops}()`. The result is that if the int64_t is `1 <<
36`, the int will be 0, since the low bits are 0. Even when some low
bits are set, a value such as `((1 << 36) + 1)` would truncate to 1,
which is wrong.
There is protection against this on 32-bit platforms, but on 64-bit
platforms, there is no check to protect us, so we add a check.
Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Reviewed-by: Ryan Moeller <ryan@iXsystems.com>
Signed-off-by: Richard Yao <richard.yao@alumni.stonybrook.edu>
Closes#13882
A symlink to i386 includes is created in the build dir on amd64 since
freebsd/freebsd-src@d07600c563
Tell git to ignore it like the other include links.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Ryan Moeller <ryan@iXsystems.com>
Closes#13719
Apply the fix from upstream.
http://www.lua.org/bugs.html#5.2.2-1https://www.opencve.io/cve/CVE-2014-5461
It should be noted that exploiting this requires the `SYS_CONFIG`
privilege, and anyone with that privilege likely has other opportunities
to do exploits, so it is unlikely that bad actors could exploit this
unless system administrators are executing untrusted ZFS Channel
Programs.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Richard Yao <richard.yao@alumni.stonybrook.edu>
Closes#13949
Coverity complained about this. An error from `hkdf_sha512()` before uio
initialization will cause pointers to uninitialized memory to be passed
to `zio_crypt_destroy_uio()`. This is a regression that was introduced
by cf63739191. Interestingly, this never
affected FreeBSD, since the FreeBSD version never had that patch ported.
Since moving uio initialization to the top of this function would slow
down the qat_crypt() path, we only move the `memset()` calls to the top
of the function. This is sufficient to fix this problem.
Reviewed-by: Ryan Moeller <ryan@iXsystems.com>
Reviewed-by: Neal Gompa <ngompa@datto.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Richard Yao <richard.yao@alumni.stonybrook.edu>
Closes#13944
Original Log Size Limit implementation blocked all writes in case of
limit reached until the TXG is committed and the log is freed. It
caused huge delays and following speed spikes in application writes.
This implementation instead smoothly throttles writes, using exactly
the same mechanism as used for dirty data.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: jxdking <lostking2008@hotmail.com>
Signed-off-by: Alexander Motin <mav@FreeBSD.org>
Sponsored-By: iXsystems, Inc.
Issue #12284Closes#13476
This reverts commit 34dbc618f5. While this
change resolved the lock contention observed for certain workloads, it
inadventantly reduced the maximum hash inserts/removes per second. This
appears to be due to the slightly higher acquisition cost of a rwlock vs
a mutex.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
I see a few issues in the issue tracker that might be aided by being
able to turn this on. We have no module parameter for it, so I would
like to add one.
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#13874
We pass sizeof (struct redact_record *) rather than sizeof (struct
redact_record). Passing the pointer size is wrong.
Coverity caught this in two places.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Richard Yao <richard.yao@alumni.stonybrook.edu>
Closes#13885
For encrypted raw receive, objset creation is delayed until a call to
dmu_recv_stream(). ZFS_PROP_SHARESMB property requires objset to be
populated when calling zpl_earlier_version(). To correctly handle the
ZFS_PROP_SHARESMB property for encrypted raw receive, this change
delays setting the property.
Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Reviewed-by: Ryan Moeller <ryan@iXsystems.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Ameer Hamza <ahamza@ixsystems.com>
Closes#13878
When iterating through children physical ashifts for vdev, prefer
ones above the maximum logical ashift, that we can actually use,
but within the administrator defined maximum.
When selecting top-level vdev ashift, do not set it to the defined
maximum in case physical ashift is even higher, but just ignore one.
Using the maximum does not prevent misaligned writes, but reduces
space efficiency. Since ZFS tries to write data sequentially and
aggregates the writes, in many cases large misanigned writes may be
not as bad as the space penalty otherwise.
Allow internal physical ashifts for vdevs higher than SHIFT_MAX.
May be one day allocator or aggregation could benefit from that.
Reduce zfs_vdev_max_auto_ashift default from 16 (64KB) to 14 (16KB),
so that ZFS may still use bigger ashifts up to SHIFT_MAX (64KB),
but only if it really has to or explicitly told to, but not as an
"optimization".
There are some read-intensive NVMe SSDs that report Preferred Write
Alignment of 64KB, and attempt to build RAIDZ2 of those leads to a
space inefficiency that can't be justified. Instead these changes
make ZFS fall back to logical ashift of 12 (4KB) by default and
only warn user that it may be suboptimal for performance.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Ryan Moeller <ryan@iXsystems.com>
Signed-off-by: Alexander Motin <mav@FreeBSD.org>
Sponsored by: iXsystems, Inc.
Closes#13798
zfs_wrlog_data_max
The upper limit of TX_WRITE log data. Once it is reached,
write operation is blocked, until log data is cleared out
after txg sync. It only counts TX_WRITE log with WR_COPIED
or WR_NEED_COPY.
Reviewed-by: Prakash Surya <prakash.surya@delphix.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: jxdking <lostking2008@hotmail.com>
Closes#12284
Use dp_dirty_pertxg[] for txg_kick(), instead of dp_dirty_total in
original code. Extra parameter "txg" is added for txg_kick(), thus it
knows which txg to kick. Also txg_kick() call is moved from
dsl_pool_need_dirty_delay() to dsl_pool_dirty_space() so that we can
know the txg number assigned for txg_kick().
Some unnecessary code regarding dp_dirty_total in txg_sync_thread() is
also cleaned up.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Matthew Ahrens <mahrens@delphix.com>
Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Signed-off-by: jxdking <lostking2008@hotmail.com>
Closes#12274
- Some optimizations for bqueue enqueue/dequeue.
- Added a fix to prevent deadlock when both bqueue_enqueue_impl()
and bqueue_dequeue() waits for signal to be triggered.
Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Reviewed-by: Ryan Moeller <ryan@iXsystems.com>
Signed-off-by: Ameer Hamza <ahamza@ixsystems.com>
Closes#13855
Coverity reported this as an out-of-bounds read.
Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Neal Gompa <ngompa@datto.com>
Signed-off-by: Richard Yao <richard.yao@alumni.stonybrook.edu>
Closes#13865
Add physical device size/capacity only for physical devices in
'zpool list -v' instead of displaying "-" in the SIZE column.
This would make it easier to see the individual device capacity and
to determine which spares are large enough to replace which devices.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Tony Hutter <hutter2@llnl.gov>
Reviewed-by: Dipak Ghosh <dipak.ghosh@hpe.com>
Signed-off-by: Akash B <akash-b@hpe.com>
Closes#12561Closes#13106
Special allocation class or dedup vdevs may have roughly the same
performance as L2ARC vdevs. Introduce a new tunable to exclude those
buffers from being cacheable on L2ARC.
Reviewed-by: Don Brady <don.brady@delphix.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: George Amanakis <gamanakis@gmail.com>
Closes#11761Closes#12285
It makes sense to free memory in smaller chunks when approaching
arc_c_min to let other kernel subsystems to free more, since after
that point we can't free anything. This also matches behavior on
Linux, where to shrinker reported only the size above arc_c_min.
Reviewed-by: Ryan Moeller <ryan@iXsystems.com>
Reviewed-by: Allan Jude <allan@klarasystems.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Alexander Motin <mav@FreeBSD.org>
Closes#13794
Coverty static analysis found these.
Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Neal Gompa <ngompa@datto.com>
Signed-off-by: Richard Yao <richard.yao@alumni.stonybrook.edu>
Closes#10989Closes#13861
As of the Linux 5.20 kernel blk_cleanup_disk() has been removed,
all callers should use put_disk().
Reviewed-by: Tony Hutter <hutter2@llnl.gov>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#13728
As of the Linux 5.20 kernel bdevname() has been removed, all
callers should use snprintf() and the "%pg" format specifier.
Reviewed-by: Tony Hutter <hutter2@llnl.gov>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#13728
It turns out that short-circuiting the EFAULT behavior on a short read
breaks things on FreeBSD. So until there's a nicer solution, let's
just revert the behavior for not-Linux.
Reference:
https://reviews.freebsd.org/R10:70f51f0e474ffe1fb74cb427423a2fba3637544d
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Tony Nguyen <tony.nguyen@delphix.com>
Reviewed-by: Brian Atkinson <batkinson@lanl.gov>
Signed-off-by: Rich Ercolani <rincebrain@gmail.com>
Closes#12698
Currently, dmu_read_uio_dnode can read 64K of a requested 1M in one
loop, get EFAULT back from zfs_uiomove() (because the iovec only holds
64k), and return EFAULT, which turns into EAGAIN on the way out. EAGAIN
gets interpreted as "I didn't read anything", the caller tries again
without consuming the 64k we already read, and we're stuck.
This apparently works on newer kernels because the caller which breaks
on older Linux kernels by happily passing along a 1M read request and a
64k iovec just requests 64k at a time.
With this, we now won't return EFAULT if we got a partial read.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Rich Ercolani <rincebrain@gmail.com>
Closes#12370Closes#12509Closes#12516
Resolve straight-line speculation warnings reported by objtool
for x86_64 assembly on Linux when CONFIG_SLS is set. See the
following LWN article for the complete details.
https://lwn.net/Articles/877845/
Reviewed-by: Ryan Moeller <ryan@iXsystems.com>
Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#13528Closes#13575
Since the assembly routines calculating SHA checksums don't use
a standard stack layout, CFI directives are needed to unroll the
stack.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Attila Fülöp <attila@fueloep.org>
Closes#11733
Move the use of the db pointer after it is freed. It's only used as
a tag so a dereference would never occur, but there's no reason we
can't invert the order to resolve the warning.
module/zfs/dbuf.c: In function 'dbuf_destroy':
module/zfs/dbuf.c:2953:17: error:
pointer 'db' may be used after 'free' [-Werror=use-after-free]
Reviewed-by: Ryan Moeller <ryan@iXsystems.com>
Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#13528Closes#13575
Move the use of the private pointer after it is freed. It's only
used as a tag so a dereference would never occur, but there's no
harm in inverting the order to resolve the warning.
module/zfs/dbuf.c: In function 'dbuf_issue_final_prefetch_done':
module/zfs/dbuf.c:3204:17: error:
pointer 'private' may be used after 'free' [-Werror=use-after-free]
Reviewed-by: Ryan Moeller <ryan@iXsystems.com>
Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#13528Closes#13575
The memcpy(), memmove(), and memset() functions have been annotated
to perform bounds checking when using FORTIFY_SOURCE. A warning is
now generted when writing beyond the end of the specified field.
Alternately, the new struct_group() macro could be used to create
an anonymous union member for use by memcpy(). However, since this
is the only place the macro would be helpful it's preferable to
restructure the code slights to avoid the need for additional
compatibility code when the macro does not exist.
https://lore.kernel.org/lkml/20211118183807.1283332-1-keescook@chromium.org/T/
Reviewed-by: Ryan Moeller <ryan@iXsystems.com>
Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#13528Closes#13575
The wrong union memory was being accessed in EdonRInit resulting in
a write beyond size of field compiler warning. Reference the correct
member to resolve the warning. The warning was correct and this in
case the mistake was harmless.
In function ‘fortify_memcpy_chk’,
inlined from ‘EdonRInit’ at zfs/module/icp/algs/edonr/edonr.c:494:3:
./include/linux/fortify-string.h:344:25: error: call to
‘__write_overflow_field’ declared with attribute warning:
detected write beyond size of field (1st parameter);
maybe use struct_group()? [-Werror=attribute-warning]
Reviewed-by: Ryan Moeller <ryan@iXsystems.com>
Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#13528Closes#13575
Restructure the code in zfs_log_xvattr() to use a lr_attr_end
structure when accessing lr_attr_t elements located after the
variable sized array. This makes the code more understandable
and resolves the accessing beyond the end of the field warnings.
Reviewed-by: Ryan Moeller <ryan@iXsystems.com>
Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#13528Closes#13575
This code should be kept inline with the upstream lua version as much
as possible. Therefore, we simply want to silence the warning. This
check was enabled by default as part of -Wall in gcc 12.1.
Reviewed-by: Ryan Moeller <ryan@iXsystems.com>
Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#13528Closes#13575
It may happen that scan bookmark points to a block that was turned
into a part of a big hole. In such case dsl_scan_visitbp() may skip
it and dsl_scan_check_resume() will not be called for it. As result
new scan suspend won't be possible until the end of the object, that
may take hours if the object is a multi-terabyte ZVOL on a slow HDD
pool, stretching TXG to all that time, creating all sorts of problems.
This patch changes the resume condition to any greater or equal block,
so even if we miss the bookmarked block, the next one we find will
delete the bookmark, allowing new suspend.
Signed-off-by: Alexander Motin <mav@FreeBSD.org>
Sponsored-By: iXsystems, Inc.
Before this change for every valid parity column raidz_parity_verify()
allocated new buffer and copied there existing data, then recalculated
the parity and compared the result with the copy. This patch removes
the memory copy, simply swapping original buffer pointers with newly
allocated empty ones for parity recalculation and comparison. Original
buffers with potentially incorrect parity data are then just freed,
while new recalculated ones are used for repair.
On a pool of 12 4-wide raidz vdevs, storing 1.5TB of 16MB blocks, this
change reduces memory traffic during scrub by 17% and total unhalted
CPU time by 25%.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Alexander Motin <mav@FreeBSD.org>
Sponsored-By: iXsystems, Inc.
Closes#13613
Issuing several scrub reads for a block we may use the parent ZIO
buffer for one of child ZIOs. If that read complete successfully,
then we won't need to copy the data explicitly. If block has only
one copy (typical for root vdev, which is also a mirror inside),
then we never need to copy -- succeed or fail as-is. Previous
code also copied data from buffer of every successfully completed
child ZIO, but that just does not make any sense.
On healthy N-wide mirror this saves all N+1 (or even more in case
of ditto blocks) memory copies for each scrubbed block, allowing
CPU to focus mostly on check-summing. For other vdev types it
should save one memory copy per block copy at root vdev.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Mark Maybee <mark.maybee@delphix.com>
Signed-off-by: Alexander Motin <mav@FreeBSD.org>
Sponsored-By: iXsystems, Inc.
Closes#13606
Block statistics calculation during scrub I/O issue in case of sorted
scrub accounted ditto blocks several times. Embedded blocks on other
side were not accounted at all. This change moves the accounting from
issue to scan stage, that fixes both problems and also allows to avoid
pool-wide locking and the lock contention it created.
Since this statistics is quite specific and is not even exposed now
anywhere, disable its calculation by default to not waste CPU time.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Alexander Motin <mav@FreeBSD.org>
Sponsored-By: iXsystems, Inc.
Closes#13579
Change math to make it like the ARC, using multiplications instead.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Alexander Motin <mav@FreeBSD.org>
Sponsored-By: iXsystems, Inc.
Closes#13591
- Introduce first element offset within a leaf. It allows to reduce
by ~50% average memmove() size when adding/removing elements. If the
added/removed element is in the first half of the leaf, we may shift
elements before it and adjust the bth_first instead of moving more
elements after it.
- Use memcpy() instead of memmove() when we know there is no overlap.
- Switch from uint64_t to uint32_t. It does not limit anything,
but 32-bit arches should appreciate it greatly in hot paths.
- Store leaf capacity in struct btree to avoid 64-bit divisions.
- Adjust zfs_btree_insert_into_leaf() to always result in balanced
leaves after splitting, no matter where the new element was inserted.
Not that we care about it much, but it should also allow B-trees with
as little as two elements per leaf instead of 4 previously.
When scrubbing pool of 12 SSDs, storing 1.5TB of 4KB zvol blocks this
reduces amount of time spent in memmove() inside the scan thread from
13.7% to 5.7% and total scrub time by ~15 seconds out of 9 minutes.
It should also reduce spacemaps load time, but I haven't measured it.
Reviewed-by: Paul Dagnelie <pcd@delphix.com>
Signed-off-by: Alexander Motin <mav@FreeBSD.org>
Sponsored-By: iXsystems, Inc.
Closes#13582
Serapheim Dimitropoulos
Mateusz Guzik
Akash B
Mark Johnston
samwyc
Richard Yao
Ryan Moeller
Alexander Motin
Brian Behlendorf
Ameer Hamza
Kevin Jin
George Amanakis
Rich Ercolani
наб
Attila Fülöp
Tino Reichardt