mirror_zfs/module
Alexander Motin dd8671459f
Reduce ZIO io_lock contention on sorted scrub
During sorted scrub multiple threads (one per vdev) are issuing many
ZIOs same time, all using the same scn->scn_zio_root ZIO as parent.
It causes huge lock contention on the single global lock on that ZIO.
Improve it by introducing per-queue null ZIOs, children to that one,
and using them instead as proxy.

For 12 SSD pool storing 1.5TB of 4KB blocks on 80-core system this
dramatically reduces lock contention and reduces scrub time from 21
minutes down to 12.5, while actual read stages (not scan) are about
3x faster, reaching 100K blocks per second per vdev.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Alexander Motin <mav@FreeBSD.org>
Sponsored-By: iXsystems, Inc.
Closes #13553
2022-06-15 14:25:08 -07:00
..
avl AVL: Remove obsolete branching optimizations 2022-06-09 15:27:36 -07:00
icp Introduce BLAKE3 checksums as an OpenZFS feature 2022-06-08 15:55:57 -07:00
lua linux: module: weld all but spl.ko into zfs.ko 2022-04-20 13:28:24 -07:00
nvpair linux: module: weld all but spl.ko into zfs.ko 2022-04-20 13:28:24 -07:00
os Fix clang 13 compilation errors 2022-06-15 14:20:28 -07:00
unicode linux: module: weld all but spl.ko into zfs.ko 2022-04-20 13:28:24 -07:00
zcommon Introduce BLAKE3 checksums as an OpenZFS feature 2022-06-08 15:55:57 -07:00
zfs Reduce ZIO io_lock contention on sorted scrub 2022-06-15 14:25:08 -07:00
zstd Tiered early abort, zstd edition 2022-05-24 09:43:22 -07:00
.gitignore Cleanup linux module kbuild files 2020-06-10 09:24:15 -07:00
Kbuild.in Add support for ARCH=um for x86 sub-architectures 2022-06-15 14:22:52 -07:00
Makefile.bsd Introduce BLAKE3 checksums as an OpenZFS feature 2022-06-08 15:55:57 -07:00
Makefile.in autoconf: use include directives instead of recursing down lib 2022-05-10 10:18:11 -07:00