zfs/module
Alexander Motin ed87d456e4 Skip dnode handles use when not needed
Neither FreeBSD nor Linux currently implement kmem_cache_set_move(),
which means dnode_move() is never called.  In such situation use of
dnode handles with respective locking to access dnode from dbuf is
a waste of time for no benefit.

This patch implements optional simplified code for such platforms,
saving at least 3 dnode lock/dereference/unlock per dbuf life cycle.
Originally I hoped to drop the handles completely to save memory,
but they are still used in dnodes allocation code, so left for now.

Before this change in CPU profiles of some workloads I saw 4-20% of
CPU time spent in zrl_add_impl()/zrl_remove(), which are gone now.

Reviewed-by: Rob Wing <rob.wing@klarasystems.com
Reviewed-by: Tony Hutter <hutter2@llnl.gov>
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 #16374
2024-07-29 14:48:12 -07:00
..
avl Suppress Clang Static Analyzer false positive in the AVL tree code. 2023-03-08 13:51:21 -08:00
icp icp: remove redundant FreeBSD check 2024-05-31 15:13:59 -07:00
lua LUA: Backport CVE-2020-24370's patch 2024-02-07 11:53:05 -08:00
nvpair xdr: header cleanup 2024-04-03 15:13:27 -07:00
os Several improvements to ARC shrinking (#16197) 2024-07-25 10:31:14 -07:00
unicode Illumos #15286: do_composition() needs sign awareness 2023-01-05 11:16:21 -08:00
zcommon ddt: add support for prefetching tables into the ARC 2024-07-26 09:16:18 -07:00
zfs Skip dnode handles use when not needed 2024-07-29 14:48:12 -07:00
zstd zstd: don't call zstd_mempool_reap if there are no buffers (#16302) 2024-07-15 14:51:37 -07:00
.gitignore FreeBSD: Ignore symlink to i386 includes 2022-08-02 16:34:23 -07:00
Kbuild.in Linux 6.9: Fix UBSAN errors in sa.c (#16380) 2024-07-23 17:13:04 -07:00
Makefile.bsd Makefile.bsd: sort and cleanup source file list 2024-04-03 15:49:22 -07:00
Makefile.in check-zstd-symbols: also ignore __pfx_ symbols 2023-09-18 09:08:41 -07:00