zfs/module
Alexander Motin 74230a5bc1
Avoid memory copy when verifying raidz/draid parity
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
2022-07-05 16:27:29 -07:00
..
avl AVL: Remove obsolete branching optimizations 2022-06-09 15:27:36 -07:00
icp Enable -Wwrite-strings 2022-06-29 14:08:54 -07:00
lua module: lua: ldo: fix pragma name 2022-06-29 14:08:59 -07:00
nvpair linux: module: weld all but spl.ko into zfs.ko 2022-04-20 13:28:24 -07:00
os Re-fix -Wwrite-strings on FreeBSD 2022-06-30 11:31:09 -07:00
unicode linux: module: weld all but spl.ko into zfs.ko 2022-04-20 13:28:24 -07:00
zcommon Enable -Wwrite-strings 2022-06-29 14:08:54 -07:00
zfs Avoid memory copy when verifying raidz/draid parity 2022-07-05 16:27:29 -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