This makes the submission method selectable at module load time via the
`zfs_vdev_disk_classic` parameter, allowing this change to be backported
to 2.2 safely, and disabled in favour of the "classic" submission method
if new problems come up.
Reviewed-by: Alexander Motin <mav@FreeBSD.org>
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#15533Closes#15588
This commit tackles a number of issues in the way BIOs (`struct bio`)
are constructed for submission to the Linux block layer.
The kernel has a hard upper limit on the number of pages/segments that
can be added to a BIO, as well as a separate limit for each device
(related to its queue depth and other scheduling characteristics).
ZFS counts the number of memory pages in the request ABD
(`abd_nr_pages_off()`, and then uses that as the number of segments to
put into the BIO, up to the hard upper limit. If it requires more than
the limit, it will create multiple BIOs.
Leaving aside the fact that page count method is wrong (see below), not
limiting to the device segment max means that the device driver will
need to split the BIO in half. This is alone is not necessarily a
problem, but it interacts with another issue to cause a much larger
problem.
The kernel function to add a segment to a BIO (`bio_add_page()`) takes a
`struct page` pointer, and offset+len within it. `struct page` can
represent a run of contiguous memory pages (known as a "compound page").
In can be of arbitrary length.
The ZFS functions that count ABD pages and load them into the BIO
(`abd_nr_pages_off()`, `bio_map()` and `abd_bio_map_off()`) will never
consider a page to be more than `PAGE_SIZE` (4K), even if the `struct
page` is for multiple pages. In this case, it will load the same `struct
page` into the BIO multiple times, with the offset adjusted each time.
With a sufficiently large ABD, this can easily lead to the BIO being
entirely filled much earlier than it could have been. This is also
further contributes to the problem caused by the incorrect segment limit
calculation, as its much easier to go past the device limit, and so
require a split.
Again, this is not a problem on its own.
The logic for "never submit more than `PAGE_SIZE`" is actually a little
more subtle. It will actually never submit a buffer that crosses a 4K
page boundary.
In practice, this is fine, as most ABDs are scattered, that is a list of
complete 4K pages, and so are loaded in as such.
Linear ABDs are typically allocated from slabs, and for small sizes they
are frequently not aligned to page boundaries. For example, a 12K
allocation can span four pages, eg:
-- 4K -- -- 4K -- -- 4K -- -- 4K --
| | | | |
:## ######## ######## ######: [1K, 4K, 4K, 3K]
Such an allocation would be loaded into a BIO as you see:
[1K, 4K, 4K, 3K]
This tends not to be a problem in practice, because even if the BIO were
filled and needed to be split, each half would still have either a start
or end aligned to the logical block size of the device (assuming 4K at
least).
---
In ideal circumstances, these shortcomings don't cause any particular
problems. Its when they start to interact with other ZFS features that
things get interesting.
Aggregation will create a "gang" ABD, which is simply a list of other
ABDs. Iterating over a gang ABD is just iterating over each ABD within
it in turn.
Because the segments are simply loaded in order, we can end up with
uneven segments either side of the "gap" between the two ABDs. For
example, two 12K ABDs might be aggregated and then loaded as:
[1K, 4K, 4K, 3K, 2K, 4K, 4K, 2K]
Should a split occur, each individual BIO can end up either having an
start or end offset that is not aligned to the logical block size, which
some drivers (eg SCSI) will reject. However, this tends not to happen
because the default aggregation limit usually keeps the BIO small enough
to not require more than one split, and most pages are actually full 4K
pages, so hitting an uneven gap is very rare anyway.
If the pool is under particular memory pressure, then an IO can be
broken down into a "gang block", a 512-byte block composed of a header
and up to three block pointers. Each points to a fragment of the
original write, or in turn, another gang block, breaking the original
data up over and over until space can be found in the pool for each of
them.
Each gang header is a separate 512-byte memory allocation from a slab,
that needs to be written down to disk. When the gang header is added to
the BIO, its a single 512-byte segment.
Pulling all this together, consider a large aggregated write of gang
blocks. This results a BIO containing lots of 512-byte segments. Given
our tendency to overfill the BIO, a split is likely, and most possible
split points will yield a pair of BIOs that are misaligned. Drivers that
care, like the SCSI driver, will reject them.
---
This commit is a substantial refactor and rewrite of much of `vdev_disk`
to sort all this out.
`vdev_bio_max_segs()` now returns the ideal maximum size for the device,
if available. There's also a tuneable `zfs_vdev_disk_max_segs` to
override this, to assist with testing.
We scan the ABD up front to count the number of pages within it, and to
confirm that if we submitted all those pages to one or more BIOs, it
could be split at any point with creating a misaligned BIO. If the
pages in the BIO are not usable (as in any of the above situations), the
ABD is linearised, and then checked again. This is the same technique
used in `vdev_geom` on FreeBSD, adjusted for Linux's variable page size
and allocator quirks.
`vbio_t` is a cleanup and enhancement of the old `dio_request_t`. The
idea is simply that it can hold all the state needed to create, submit
and return multiple BIOs, including all the refcounts, the ABD copy if
it was needed, and so on. Apart from what I hope is a clearer interface,
the major difference is that because we know how many BIOs we'll need up
front, we don't need the old overflow logic that would grow the BIO
array, throw away all the old work and restart. We can get it right from
the start.
Reviewed-by: Alexander Motin <mav@FreeBSD.org>
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#15533Closes#15588
Similar to DDT make BRT data and indirect block sizes configurable
via module parameters. I am not sure what would be the best yet,
but similar to DDT 4KB blocks kill all chances of compression on
vdev with ashift=12 or more, that on my tests reaches 3x.
While here, fix documentation for respective DDT parameters.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Alexander Motin <mav@FreeBSD.org>
Sponsored by: iXsystems, Inc.
Closes#15967
- add column for TRIM ZIOs
- remove R from ZIO_STAGE_ISSUE_ASYNC, never happened
- remove I from ZIO_STAGE_VDEV_IO_DONE, never happened
Sponsored-by: Klara, Inc.
Sponsored-by: Wasabi Technology, Inc.
Reviewed by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Rob Norris <rob.norris@klarasystems.com>
Closes#15959
The recently added '-e' option (PR #15769) missed adding the
new option in the online `zpool status` help command. This
adds the options and reorders a couple of the other options
that were not listed alphabetically.
Reviewed-by: Brian Atkinson <batkinson@lanl.gov>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Cameron Harr <harr1@llnl.gov>
Closes#16008
This changes taskq_thread_should_stop() to limit maximum exit rate
for idle threads to one per 5 seconds. I believe the previous one
was broken, not allowing any thread exits for tasks arriving more
than one at a time and so completing while others are running.
Also while there:
- Remove taskq_thread_spawn() calls on task allocation errors.
- Remove extra taskq_thread_should_stop() call.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Rich Ercolani <rincebrain@gmail.com>
Signed-off-by: Alexander Motin <mav@FreeBSD.org>
Sponsored by: iXsystems, Inc.
Closes#15873
Fixes a small inaccuracy in the description of snapshot
atomicity
zfs-snapshot(8) appears to contain a small error. The existing
version reads "Snapshots are taken atomically, so that all
snapshots correspond to the same moment in time." Per
zfs_main.c, which in do_snapshot() simply loops over argv, this
does not appear to be correct when multiple snapshots are
specified explicitly on the command line. I believe the intent
of the man page was to say that *recursive* snapshots are all
created atomically.
This proposed change fixes that error. Because the existing
statement may confuse some readers anyway, the commit also also
adds a small amount of general explanatory information that may
be helpful.
The change also adds an introductory sentence that summarizes
what 'zfs snapshot' does in the first place. In that sentence,
the text "different datasets" is intended to indicate that
(again per the code) the same dataset cannot be specified
multiple times on the command line.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Shawn Bayern <sbayern@law.fsu.edu>
Closes#15857
Because "filesystem" and "volume" are just too long!
Sponsored-by: https://despairlabs.com/sponsor/
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Rob Norris <robn@despairlabs.com>
Closes#15864
Slow disk response times can be indicative of a failing drive. ZFS
currently tracks slow I/Os (slower than zio_slow_io_ms) and generates
events (ereport.fs.zfs.delay). However, no action is taken by ZED,
like is done for checksum or I/O errors. This change adds slow disk
diagnosis to ZED which is opt-in using new VDEV properties:
VDEV_PROP_SLOW_IO_N
VDEV_PROP_SLOW_IO_T
If multiple VDEVs in a pool are undergoing slow I/Os, then it skips
the zpool_vdev_degrade().
Sponsored-By: OpenDrives Inc.
Sponsored-By: Klara Inc.
Reviewed-by: Tony Hutter <hutter2@llnl.gov>
Reviewed-by: Allan Jude <allan@klarasystems.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Co-authored-by: Rob Wing <rob.wing@klarasystems.com>
Signed-off-by: Don Brady <don.brady@klarasystems.com>
Closes#15469
When very large pools are present, it can be laborious to find
reasons for why a pool is degraded and/or where an unhealthy vdev
is. This option filters out vdevs that are ONLINE and with no errors
to make it easier to see where the issues are. Root and parents of
unhealthy vdevs will always be printed.
Testing:
ZFS errors and drive failures for multiple vdevs were simulated with
zinject.
Sample vdev listings with '-e' option
- All vdevs healthy
NAME STATE READ WRITE CKSUM
iron5 ONLINE 0 0 0
- ZFS errors
NAME STATE READ WRITE CKSUM
iron5 ONLINE 0 0 0
raidz2-5 ONLINE 1 0 0
L23 ONLINE 1 0 0
L24 ONLINE 1 0 0
L37 ONLINE 1 0 0
- Vdev faulted
NAME STATE READ WRITE CKSUM
iron5 DEGRADED 0 0 0
raidz2-6 DEGRADED 0 0 0
L67 FAULTED 0 0 0 too many errors
- Vdev faults and data errors
NAME STATE READ WRITE CKSUM
iron5 DEGRADED 0 0 0
raidz2-1 DEGRADED 0 0 0
L2 FAULTED 0 0 0 too many errors
raidz2-5 ONLINE 1 0 0
L23 ONLINE 1 0 0
L24 ONLINE 1 0 0
L37 ONLINE 1 0 0
raidz2-6 DEGRADED 0 0 0
L67 FAULTED 0 0 0 too many errors
- Vdev missing
NAME STATE READ WRITE CKSUM
iron5 DEGRADED 0 0 0
raidz2-6 DEGRADED 0 0 0
L67 UNAVAIL 3 1 0
- Slow devices when -s provided with -e
NAME STATE READ WRITE CKSUM SLOW
iron5 DEGRADED 0 0 0 -
raidz2-5 DEGRADED 0 0 0 -
L10 FAULTED 0 0 0 0 external device fault
L51 ONLINE 0 0 0 14
Reviewed-by: Tony Hutter <hutter2@llnl.gov>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Cameron Harr <harr1@llnl.gov>
Closes#15769
On Linux the ioctl_ficlonerange() and ioctl_ficlone() system calls
are expected to either fully clone the specified range or return an
error. The range may be for an entire file. While internally ZFS
supports cloning partial ranges there's no way to return the length
cloned to the caller so we need to make this all or nothing.
As part of this change support for the REMAP_FILE_CAN_SHORTEN flag
has been added. When REMAP_FILE_CAN_SHORTEN is set zfs_clone_range()
will return a shortened range when encountering pending dirty records.
When it's clear zfs_clone_range() will block and wait for the records
to be written out allowing the blocks to be cloned.
Furthermore, the file range lock is held over the region being cloned
to prevent it from being modified while cloning. This doesn't quite
provide an atomic semantics since if an error is encountered only a
portion of the range may be cloned. This will be converted to an
error if REMAP_FILE_CAN_SHORTEN was not provided and returned to the
caller. However, the destination file range is left in an undefined
state.
A test case has been added which exercises this functionality by
verifying that `cp --reflink=never|auto|always` works correctly.
Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#15728Closes#15842
zpool-iostat.8: Updated time(2) -> time(1) to align to manual page
zpool-list.8: Updated time(2) -> time(1) to align to manual page
zpool-status.8: Updated time(2) -> time(1) to align to manual page
zpool-wait.8: Update time(2) -> time(1) to align to manual page
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Christopher Davidson <christopher.davidson@gmail.com>
Closes#15823
Add `zpool` flags to control the slot power to drives. This assumes
your SAS or NVMe enclosure supports slot power control via sysfs.
The new `--power` flag is added to `zpool offline|online|clear`:
zpool offline --power <pool> <device> Turn off device slot power
zpool online --power <pool> <device> Turn on device slot power
zpool clear --power <pool> [device] Turn on device slot power
If the ZPOOL_AUTO_POWER_ON_SLOT env var is set, then the '--power'
option is automatically implied for `zpool online` and `zpool clear`
and does not need to be passed.
zpool status also gets a --power option to print the slot power status.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Mart Frauenlob <AllKind@fastest.cc>
Signed-off-by: Tony Hutter <hutter2@llnl.gov>
Closes#15662
We are finding that as customers get larger and faster machines
(hundreds of cores, large NVMe-backed pools) they keep hitting
relatively low performance ceilings. Our profiling work almost always
finds that they're running into bottlenecks on the SPA IO taskqs.
Unfortunately there's often little we can advise at that point, because
there's very few ways to change behaviour without patching.
This commit adds two load-time parameters `zio_taskq_read` and
`zio_taskq_write` that can configure the READ and WRITE IO taskqs
directly.
This achieves two goals: it gives operators (and those that support
them) a way to tune things without requiring a custom build of OpenZFS,
which is often not possible, and it lets us easily try different config
variations in a variety of environments to inform the development of
better defaults for these kind of systems.
Because tuning the IO taskqs really requires a fairly deep understanding
of how IO in ZFS works, and generally isn't needed without a pretty
serious workload and an ability to identify bottlenecks, only minimal
documentation is provided. Its expected that anyone using this is going
to have the source code there as well.
Sponsored-by: Klara, Inc.
Sponsored-by: Wasabi Technology, Inc.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Rob Norris <rob.norris@klarasystems.com>
Closes#15675
When two datasets share the same master encryption key, it is safe
to clone encrypted blocks. Currently only snapshots and clones
of a dataset share with it the same encryption key.
Added a test for:
- Clone from encrypted sibling to encrypted sibling with
non encrypted parent
- Clone from encrypted parent to inherited encrypted child
- Clone from child to sibling with encrypted parent
- Clone from snapshot to the original datasets
- Clone from foreign snapshot to a foreign dataset
- Cloning from non-encrypted to encrypted datasets
- Cloning from encrypted to non-encrypted datasets
Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Original-patch-by: Pawel Jakub Dawidek <pawel@dawidek.net>
Signed-off-by: Kay Pedersen <mail@mkwg.de>
Closes#15544
Same idea as the dedup stats, but for block cloning.
Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Reviewed-by: Kay Pedersen <mail@mkwg.de>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Rob Norris <robn@despairlabs.com>
Closes#15541
Copy the disable parameter that FreeBSD implemented, and extend it to
work on Linux as well, until we're sure this is stable.
Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Rich Ercolani <rincebrain@gmail.com>
Closes#15529
It is unused for 3 years since #10576.
Reviewed-by: George Melikov <mail@gmelikov.ru>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Alexander Motin <mav@FreeBSD.org>
Sponsored by: iXsystems, Inc.
Closes#15507
This commit updates zpool-features.7 man page to add newly added
zpool features to grub2 compatibility list.
Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Umer Saleem <usaleem@ixsystems.com>
Closes#15505
Current L2ARC write rate and headroom parameters are very conservative:
l2arc_write_max=8M and l2arc_headroom=2 (ie: a full L2ARC writes at
8 MB/s, scanning 16/32 MB of ARC tail each time; a warming L2ARC runs
at 2x these rates).
These values were selected 15+ years ago based on then-current SSDs
size, performance and endurance. Today we have multi-TB, fast and
cheap SSDs which can sustain much higher read/write rates.
For this reason, this patch increases l2arc_write_max to 32M and
l2arc_headroom to 8 (4x increase for both).
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Signed-off-by: Gionatan Danti <g.danti@assyoma.it>
Closes#15457
This feature allows disks to be added one at a time to a RAID-Z group,
expanding its capacity incrementally. This feature is especially useful
for small pools (typically with only one RAID-Z group), where there
isn't sufficient hardware to add capacity by adding a whole new RAID-Z
group (typically doubling the number of disks).
== Initiating expansion ==
A new device (disk) can be attached to an existing RAIDZ vdev, by
running `zpool attach POOL raidzP-N NEW_DEVICE`, e.g. `zpool attach tank
raidz2-0 sda`. The new device will become part of the RAIDZ group. A
"raidz expansion" will be initiated, and the new device will contribute
additional space to the RAIDZ group once the expansion completes.
The `feature@raidz_expansion` on-disk feature flag must be `enabled` to
initiate an expansion, and it remains `active` for the life of the pool.
In other words, pools with expanded RAIDZ vdevs can not be imported by
older releases of the ZFS software.
== During expansion ==
The expansion entails reading all allocated space from existing disks in
the RAIDZ group, and rewriting it to the new disks in the RAIDZ group
(including the newly added device).
The expansion progress can be monitored with `zpool status`.
Data redundancy is maintained during (and after) the expansion. If a
disk fails while the expansion is in progress, the expansion pauses
until the health of the RAIDZ vdev is restored (e.g. by replacing the
failed disk and waiting for reconstruction to complete).
The pool remains accessible during expansion. Following a reboot or
export/import, the expansion resumes where it left off.
== After expansion ==
When the expansion completes, the additional space is available for use,
and is reflected in the `available` zfs property (as seen in `zfs list`,
`df`, etc).
Expansion does not change the number of failures that can be tolerated
without data loss (e.g. a RAIDZ2 is still a RAIDZ2 even after
expansion).
A RAIDZ vdev can be expanded multiple times.
After the expansion completes, old blocks remain with their old
data-to-parity ratio (e.g. 5-wide RAIDZ2, has 3 data to 2 parity), but
distributed among the larger set of disks. New blocks will be written
with the new data-to-parity ratio (e.g. a 5-wide RAIDZ2 which has been
expanded once to 6-wide, has 4 data to 2 parity). However, the RAIDZ
vdev's "assumed parity ratio" does not change, so slightly less space
than is expected may be reported for newly-written blocks, according to
`zfs list`, `df`, `ls -s`, and similar tools.
Sponsored-by: The FreeBSD Foundation
Sponsored-by: iXsystems, Inc.
Sponsored-by: vStack
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Mark Maybee <mark.maybee@delphix.com>
Authored-by: Matthew Ahrens <mahrens@delphix.com>
Contributions-by: Fedor Uporov <fuporov.vstack@gmail.com>
Contributions-by: Stuart Maybee <stuart.maybee@comcast.net>
Contributions-by: Thorsten Behrens <tbehrens@outlook.com>
Contributions-by: Fmstrat <nospam@nowsci.com>
Contributions-by: Don Brady <dev.fs.zfs@gmail.com>
Signed-off-by: Don Brady <dev.fs.zfs@gmail.com>
Closes#15022
As part of transaction group commit, dsl_pool_sync() sequentially calls
dsl_dataset_sync() for each dirty dataset, which subsequently calls
dmu_objset_sync(). dmu_objset_sync() in turn uses up to 75% of CPU
cores to run sync_dnodes_task() in taskq threads to sync the dirty
dnodes (files).
There are two problems:
1. Each ZVOL in a pool is a separate dataset/objset having a single
dnode. This means the objsets are synchronized serially, which
leads to a bottleneck of ~330K blocks written per second per pool.
2. In the case of multiple dirty dnodes/files on a dataset/objset on a
big system they will be sync'd in parallel taskq threads. However,
it is inefficient to to use 75% of CPU cores of a big system to do
that, because of (a) bottlenecks on a single write issue taskq, and
(b) allocation throttling. In addition, if not for the allocation
throttling sorting write requests by bookmarks (logical address),
writes for different files may reach space allocators interleaved,
leading to unwanted fragmentation.
The solution to both problems is to always sync no more and (if
possible) no fewer dnodes at the same time than there are allocators
the pool.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Signed-off-by: Edmund Nadolski <edmund.nadolski@ixsystems.com>
Closes#15197
Currently, zvol threading can be switched through the zvol_request_sync
module parameter system-wide. By making it a zvol property, zvol
threading can be switched per zvol.
Reviewed-by: Tony Hutter <hutter2@llnl.gov>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Signed-off-by: Ameer Hamza <ahamza@ixsystems.com>
Closes#15409
Commits 518b487 and 23bdb07 changed the default ARC size limit on
Linux systems to 1/2 of physical memory, which has become too
strict for modern systems with large amounts of RAM. This patch
changes the default limit to match that of FreeBSD, so ZFS may
have a unified value on both platforms.
Reviewed-by: George Melikov <mail@gmelikov.ru>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Edmund Nadolski <edmund.nadolski@ixsystems.com>
Closes#15437
This reverts commit aefb6a2bd6.
aefb6a2bd temporally disabled blk-mq until we could fix a fix for
Signed-off-by: Tony Hutter <hutter2@llnl.gov>
Closes#15439
... by checking that previous block is fully written and flushed.
It allows to skip commit delays since we can give up on aggregation
in that case. This removes zil_min_commit_timeout parameter, since
for single-threaded workloads it is not needed at all, while on very
fast devices even some multi-threaded workloads may get detected as
single-threaded and still bypass the wait. To give multi-threaded
workloads more aggregation chances increase zfs_commit_timeout_pct
from 5 to 10%, as they should suffer less from additional latency.
Also single-threaded workloads detection allows in perspective better
prediction of the next block size.
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#15381
ZFS prefetch is currently governed by the zfs_prefetch_disable
tunable. However, this is a module-wide settings - if a specific
dataset benefits from prefetch, while others have issue with it,
an optimal solution does not exists.
This commit introduce the "prefetch" tri-state property, which enable
granular control (at dataset/volume level) for prefetching.
This patch does not remove the zfs_prefetch_disable, which remains
a system-wide switch for enable/disable prefetch. However, to avoid
duplication, it would be preferable to deprecate and then remove
the module tunable.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Reviewed-by: Ameer Hamza <ahamza@ixsystems.com>
Signed-off-by: Gionatan Danti <g.danti@assyoma.it>
Co-authored-by: Gionatan Danti <g.danti@assyoma.it>
Closes#15237Closes#15436
For synchronous write workloads with large IO sizes, a pool configured
with a slog performs worse than one with an embedded zil:
sequential_writes 1m sync ios, 16 threads
Write IOPS: 1292 438 -66.10%
Write Bandwidth: 1323570 448910 -66.08%
Write Latency: 12128400 36330970 3.0x
sequential_writes 1m sync ios, 32 threads
Write IOPS: 1293 430 -66.74%
Write Bandwidth: 1324184 441188 -66.68%
Write Latency: 24486278 74028536 3.0x
The reason is the `zil_slog_bulk` variable. In `zil_lwb_write_open`,
if a zil block is greater than 768K, the priority of the write is
downgraded from sync to async. Increasing the value allows greater
throughput. To select a value for this PR, I ran an fio workload with
the following values for `zil_slog_bulk`:
zil_slog_bulk KiB/s
1048576 422132
2097152 478935
4194304 533645
8388608 623031
12582912 827158
16777216 1038359
25165824 1142210
33554432 1211472
50331648 1292847
67108864 1308506
100663296 1306821
134217728 1304998
At 64M, the results with a slog are now improved to parity with an
embedded zil:
sequential_writes 1m sync ios, 16 threads
Write IOPS: 438 1288 2.9x
Write Bandwidth: 448910 1319062 2.9x
Write Latency: 36330970 12163408 -66.52%
sequential_writes 1m sync ios, 32 threads
Write IOPS: 430 1290 3.0x
Write Bandwidth: 441188 1321693 3.0x
Write Latency: 74028536 24519698 -66.88%
None of the other tests in the performance suite (run with a zil or
slog) had a significant change, including the random_write_zil tests,
which use multiple datasets.
Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Reviewed-by: Tony Nguyen <tony.nguyen@delphix.com>
Signed-off-by: John Wren Kennedy <john.kennedy@delphix.com>
Closes#14378
There was a report of zvol data loss (#15351) after enabling blk-mq on a
zvol backed with 16k physical block sized disks. Out of an abundance of
caution, do not allow the user to enable blk-mq until we can look into
the issue.
Note that blk-mq was not enabled by default on zvols. It was always
opt-in via the zvol_use_blk_mq module parameter.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Tony Nguyen <tony.nguyen@delphix.com>
Signed-off-by: Tony Hutter <hutter2@llnl.gov>
Addresses: #15351Closes#15378
Benchmarks show that at certain write sizes range lock/unlock take
not so much time as extra memory copy. The exact threshold is not
obvious due to other overheads, but it is definitely lower than
~63KB used before. Make it configurable, defaulting at 7.5KB,
that is 8KB of nearest malloc() size minus itx and lr structs.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Alexander Motin <mav@FreeBSD.org>
Sponsored by: iXsystems, Inc.
Closes#15353
Here I'm trying to succinctly introduce the concept, the basics of its
construction, how its different to dedup, how to use it, and where its
limitations lie, in four paragraphs and with enough searchable terms to
help the reader find more information both within OpenZFS and elsewhere.
Phew.
Sponsored-By: Klara, Inc.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Rob Norris <rob.norris@klarasystems.com>
Closes#15362
Before this change ZFS created threads for 50% of CPUs for each top-
level vdev. Plus it created the same number of threads for embedded
log groups (that have only one metaslab and don't need any preload).
As result, on system with 80 CPUs and pool of 60 vdevs this resulted
in 4800 metaslab preload threads, that is absolutely insane.
This patch changes the preload threads to 50% of CPUs in one taskq
per pool, so on the mentioned system it will be only 40 threads.
Among other things this fixes zdb on the mentioned system and pool
on FreeBSD, that failed to create so many threads in one process.
Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Alexander Motin <mav@FreeBSD.org>
Sponsored by: iXsystems, Inc.
Closes#15319
This commit adds '-u' flag for zfs set operation. With this flag,
mountpoint, sharenfs and sharesmb properties can be updated
without actually mounting or sharing the dataset.
Previously, if dataset was unmounted, and mountpoint property was
updated, dataset was not mounted after the update. This behavior
is changed in #15240. We mount the dataset whenever mountpoint
property is updated, regardless if it's mounted or not.
To provide the user with option to keep the dataset unmounted and
still update the mountpoint without mounting the dataset, '-u'
flag can be used.
If any of mountpoint, sharenfs or sharesmb properties are updated
with '-u' flag, the property is set to desired value but the
operation to (re/un)mount and/or (re/un)share the dataset is not
performed and dataset remains as it was before.
Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Umer Saleem <usaleem@ixsystems.com>
Closes#15322
Have libzfs call a special `zfs_prepare_disk` script before a disk is
included into the pool. The user can edit this script to add things
like a disk firmware update or a disk health check. Use of the script
is totally optional. See the zfs_prepare_disk manpage for full details.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Tony Hutter <hutter2@llnl.gov>
Closes#15243
Currently redaction bookmarks and their associated redaction lists
have a relatively low limit of 36 redaction snapshots. This is imposed
by the number of snapshot GUIDs that fit in the bonus buffer of the
redaction list object. While this is more than enough for most use
cases, there are some limited cases where larger numbers would be
useful to support.
We tweak the redaction list creation code to use a spill block if
the number of redaction snapshots is above the amount that would fit
in the bonus buffer. We also make a small change to allow spill blocks
to be use for types of data besides SA. In order to fully leverage
this logic, we also change the redaction code to use vmem_alloc, to
handle extremely large allocations if needed. Finally, small tweaks
were made to the zfs commands and the test suite.
Reviewed-by: Matthew Ahrens <mahrens@delphix.com>
Signed-off-by: Paul Dagnelie <pcd@delphix.com>
Closes#15018
Try to clarify wording to reduce zpool add incidents.
Add an attach example.
Reviewed-by: Rich Ercolani <Rincebrain@gmail.com>
Reviewed-by: George Melikov <mail@gmelikov.ru>
Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Signed-off-by: Paul Dagnelie <pcd@delphix.com>
Closes#15179
- Distribute zfs-[un]jail.8 on FreeBSD and zfs-[un]zone.8 on Linux
- zfsprops.7: mirror zoned/jailed, only available on respective platforms
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Ahelenia Ziemiańska <nabijaczleweli@nabijaczleweli.xyz>
Closes#15161
POSIX timers target the process, not the thread (as does SIGINFO),
so we need to block it in the main thread which will die if interrupted.
Ref: https://101010.pl/@ed1conf@bsd.network/110731819189629373
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Jorgen Lundman <lundman@lundman.net>
Signed-off-by: Ahelenia Ziemiańska <nabijaczleweli@nabijaczleweli.xyz>
Closes#15113
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
- 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
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#14717Closes#15052
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
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
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
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
Rob Norris
Alexander Motin
Cameron Harr
Shawn Bayern
Rob N
Don Brady
Cameron Harr
Brian Behlendorf
Chris Davidson
Jose Luis Duran
Tony Hutter
oromenahar
Rich Ercolani
Umer Saleem
shodanshok
ednadolski-ix
Ameer Hamza
John Wren Kennedy
Laura Hild
Serapheim Dimitropoulos
Paul Dagnelie
наб
Alan Somers
Mateusz Piotrowski
Laevos