mirror_zfs/include
Rob N 6930ecbb75
spa: make read/write queues configurable
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
2023-12-20 14:17:14 -08:00
..
os spa: make read/write queues configurable 2023-12-20 14:17:14 -08:00
sys dmu: Allow buffer fills to fail 2023-12-15 09:51:41 -08:00
.gitignore OpenZFS restructuring - move platform specific sources 2019-09-06 11:26:26 -07:00
cityhash.h libzfs: convert to -fvisibility=hidden 2021-06-03 13:17:55 -07:00
libnvpair.h nvpair: Constify string functions 2023-03-14 15:25:50 -07:00
libuutil_common.h Replace dead opensolaris.org license link 2022-07-11 14:16:13 -07:00
libuutil_impl.h libuutil: deobfuscate internal pointers 2022-11-03 09:57:05 -07:00
libuutil.h Cleanup: Remove unused uu_pname code 2022-09-19 17:33:52 -07:00
libzfs_core.h Teach zpool scrub to scrub only blocks in error log 2023-05-18 11:59:42 -07:00
libzfs.h RAID-Z expansion feature 2023-11-08 10:19:41 -08:00
libzfsbootenv.h lib{efi,avl,share,tpool,zfs_core,zfsbootenv,zutil}: -fvisibility=hidden 2021-06-09 17:04:32 -07:00
libzutil.h zed: misc vdev_enc_sysfs_path fixes 2023-11-07 09:09:24 -08:00
Makefile.am brt: lift internal definitions into _impl header 2023-11-27 13:34:43 -08:00
thread_pool.h Replace dead opensolaris.org license link 2022-07-11 14:16:13 -07:00
zfeature_common.h RAID-Z expansion feature 2023-11-08 10:19:41 -08:00
zfs_comutil.h Replace dead opensolaris.org license link 2022-07-11 14:16:13 -07:00
zfs_deleg.h Replace dead opensolaris.org license link 2022-07-11 14:16:13 -07:00
zfs_fletcher.h Drop lying to the compiler in the fletcher4 code 2023-03-24 10:29:19 -07:00
zfs_namecheck.h Replace dead opensolaris.org license link 2022-07-11 14:16:13 -07:00
zfs_prop.h Replace dead opensolaris.org license link 2022-07-11 14:16:13 -07:00