zfs/include/sys
Alexander Motin 9dcdee7889
Optimize microzaps
Microzap on-disk format does not include a hash tree, expecting one to
be built in RAM during mzap_open().  The built tree is linked to DMU
user buffer, freed when original DMU buffer is dropped from cache. I've
found that workloads accessing many large directories and having active
eviction from DMU cache spend significant amount of time building and
then destroying the trees.  I've also found that for each 64 byte mzap
element additional 64 byte tree element is allocated, that is a waste
of memory and CPU caches.

Improve memory efficiency of the hash tree by switching from AVL-tree
to B-tree.  It allows to save 24 bytes per element just on pointers.
Save 32 bits on mze_hash by storing only upper 32 bits since lower 32
bits are always zero for microzaps.  Save 16 bits on mze_chunkid, since
microzap can never have so many elements.  Respectively with the 16 bits
there can be no more than 16 bits of collision differentiators.  As
result, struct mzap_ent now drops from 48 (rounded to 64) to 8 bytes.

Tune B-trees for small data.  Reduce BTREE_CORE_ELEMS from 128 to 126
to allow struct zfs_btree_core in case of 8 byte elements to pack into
2KB instead of 4KB.  Aside of the microzaps it should also help 32bit
range trees.  Allow custom B-tree leaf size to reduce memmove() time.

Split zap_name_alloc() into zap_name_alloc() and zap_name_init_str().
It allows to not waste time allocating/freeing memory when processing
multiple names in a loop during mzap_open().

Together on a pool with 10K directories of 1800 files each and DMU
cache limited to 128MB this reduces time of `find . -name zzz` by 41%
from 7.63s to 4.47s, and saves additional ~30% of CPU time on the DMU
cache reclamation.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Matthew Ahrens <mahrens@delphix.com>
Reviewed-by: Ryan Moeller <ryan@iXsystems.com>
Signed-off-by:	Alexander Motin <mav@FreeBSD.org>
Sponsored by:	iXsystems, Inc.
Closes #14039
2022-10-20 11:57:15 -07:00
..
crypto Replace dead opensolaris.org license link 2022-07-11 14:16:13 -07:00
fm Cleanup: Specify unsignedness on things that should not be signed 2022-09-27 16:42:41 -07:00
fs Add options to zfs redundant_metadata property 2022-10-19 17:07:51 -07:00
lua autoconf: single-step includes 2022-05-10 10:18:51 -07:00
sysevent zed: Fix config_sync autoexpand flood 2022-09-08 10:32:30 -07:00
zstd Unbreak zstd build on sparc64 2022-05-25 09:18:49 -07:00
abd.h Replace dead opensolaris.org license link 2022-07-11 14:16:13 -07:00
abd_impl.h Replace dead opensolaris.org license link 2022-07-11 14:16:13 -07:00
aggsum.h More aggsum optimizations 2021-06-07 09:02:47 -07:00
arc.h Cleanup: Specify unsignedness on things that should not be signed 2022-09-27 16:42:41 -07:00
arc_impl.h Cleanup: 64-bit kernel module parameters should use fixed width types 2022-10-13 10:03:29 -07:00
avl.h Replace dead opensolaris.org license link 2022-07-11 14:16:13 -07:00
avl_impl.h Replace dead opensolaris.org license link 2022-07-11 14:16:13 -07:00
bitops.h Replace dead opensolaris.org license link 2022-07-11 14:16:13 -07:00
blake3.h Fix BLAKE3 tuneable and module loading on Linux and FreeBSD 2022-09-16 14:25:53 -07:00
blkptr.h OpenZFS 8067 - zdb should be able to dump literal embedded block pointer 2017-07-07 11:28:01 -07:00
bplist.h Replace dead opensolaris.org license link 2022-07-11 14:16:13 -07:00
bpobj.h Replace dead opensolaris.org license link 2022-07-11 14:16:13 -07:00
bptree.h Replace dead opensolaris.org license link 2022-07-11 14:16:13 -07:00
bqueue.h zfs recv hangs if max recordsize is less than received recordsize 2022-09-16 13:52:25 -07:00
btree.h Optimize microzaps 2022-10-20 11:57:15 -07:00
dataset_kstats.h Add support for per dataset zil stats and use wmsum counters 2022-07-20 17:14:06 -07:00
dbuf.h Dynamically size dbuf hash mutex array 2022-09-22 12:59:56 -07:00
ddt.h Replace dead opensolaris.org license link 2022-07-11 14:16:13 -07:00
dmu.h Add options to zfs redundant_metadata property 2022-10-19 17:07:51 -07:00
dmu_impl.h Replace dead opensolaris.org license link 2022-07-11 14:16:13 -07:00
dmu_objset.h Replace dead opensolaris.org license link 2022-07-11 14:16:13 -07:00
dmu_recv.h Implement a new type of zfs receive: corrective receive (-c) 2022-07-28 15:52:46 -07:00
dmu_redact.h Replace dead opensolaris.org license link 2022-07-11 14:16:13 -07:00
dmu_send.h Replace dead opensolaris.org license link 2022-07-11 14:16:13 -07:00
dmu_traverse.h Replace dead opensolaris.org license link 2022-07-11 14:16:13 -07:00
dmu_tx.h Replace dead opensolaris.org license link 2022-07-11 14:16:13 -07:00
dmu_zfetch.h Cleanup: 64-bit kernel module parameters should use fixed width types 2022-10-13 10:03:29 -07:00
dnode.h Replace dead opensolaris.org license link 2022-07-11 14:16:13 -07:00
dsl_bookmark.h Remaining {=> const} char|void *tag 2022-06-29 14:08:59 -07:00
dsl_crypt.h Fix zpool status in case of unloaded keys 2022-08-22 17:42:01 -07:00
dsl_dataset.h Add zfs.sync.snapshot_rename 2022-09-02 13:31:19 -07:00
dsl_deadlist.h Cleanup: 64-bit kernel module parameters should use fixed width types 2022-10-13 10:03:29 -07:00
dsl_deleg.h Replace dead opensolaris.org license link 2022-07-11 14:16:13 -07:00
dsl_destroy.h Replace dead opensolaris.org license link 2022-07-11 14:16:13 -07:00
dsl_dir.h Add DD_FIELD string for snapshots_changed property 2022-09-02 13:33:50 -07:00
dsl_pool.h Cleanup: 64-bit kernel module parameters should use fixed width types 2022-10-13 10:03:29 -07:00
dsl_prop.h Replace dead opensolaris.org license link 2022-07-11 14:16:13 -07:00
dsl_scan.h Replace dead opensolaris.org license link 2022-07-11 14:16:13 -07:00
dsl_synctask.h Replace dead opensolaris.org license link 2022-07-11 14:16:13 -07:00
dsl_userhold.h Replace dead opensolaris.org license link 2022-07-11 14:16:13 -07:00
edonr.h OpenZFS 4185 - add new cryptographic checksums to ZFS: SHA-512, Skein, Edon-R 2016-10-03 14:51:15 -07:00
efi_partition.h Replace dead opensolaris.org license link 2022-07-11 14:16:13 -07:00
frame.h Linux 5.10 compat: frame.h renamed objtool.h 2020-11-02 22:01:10 +00:00
hkdf.h Encryption patch follow-up 2017-10-11 16:54:48 -04:00
metaslab.h Replace dead opensolaris.org license link 2022-07-11 14:16:13 -07:00
metaslab_impl.h Replace dead opensolaris.org license link 2022-07-11 14:16:13 -07:00
mmp.h Cleanup: 64-bit kernel module parameters should use fixed width types 2022-10-13 10:03:29 -07:00
mntent.h Expose ZFS dataset case sensitivity setting via sb_opts 2022-07-14 10:38:16 -07:00
mod.h linux: module: weld all but spl.ko into zfs.ko 2022-04-20 13:28:24 -07:00
multilist.h Re-embed multilist_t storage 2021-06-10 10:42:31 -06:00
nvpair.h Replace dead opensolaris.org license link 2022-07-11 14:16:13 -07:00
nvpair_impl.h Replace dead opensolaris.org license link 2022-07-11 14:16:13 -07:00
objlist.h Implement Redacted Send/Receive 2019-06-19 09:48:12 -07:00
pathname.h Replace dead opensolaris.org license link 2022-07-11 14:16:13 -07:00
qat.h Replace dead opensolaris.org license link 2022-07-11 14:16:13 -07:00
range_tree.h Replace dead opensolaris.org license link 2022-07-11 14:16:13 -07:00
rrwlock.h Replace dead opensolaris.org license link 2022-07-11 14:16:13 -07:00
sa.h Replace dead opensolaris.org license link 2022-07-11 14:16:13 -07:00
sa_impl.h Replace dead opensolaris.org license link 2022-07-11 14:16:13 -07:00
skein.h OpenZFS 4185 - add new cryptographic checksums to ZFS: SHA-512, Skein, Edon-R 2016-10-03 14:51:15 -07:00
spa.h Cleanup: 64-bit kernel module parameters should use fixed width types 2022-10-13 10:03:29 -07:00
spa_checkpoint.h Replace dead opensolaris.org license link 2022-07-11 14:16:13 -07:00
spa_checksum.h Replace dead opensolaris.org license link 2022-07-11 14:16:13 -07:00
spa_impl.h Cleanup: Specify unsignedness on things that should not be signed 2022-09-27 16:42:41 -07:00
spa_log_spacemap.h Replace dead opensolaris.org license link 2022-07-11 14:16:13 -07:00
space_map.h Replace dead opensolaris.org license link 2022-07-11 14:16:13 -07:00
space_reftree.h Replace dead opensolaris.org license link 2022-07-11 14:16:13 -07:00
sysevent.h Replace dead opensolaris.org license link 2022-07-11 14:16:13 -07:00
txg.h Cleanup: Specify unsignedness on things that should not be signed 2022-09-27 16:42:41 -07:00
txg_impl.h Replace dead opensolaris.org license link 2022-07-11 14:16:13 -07:00
u8_textprep.h Replace dead opensolaris.org license link 2022-07-11 14:16:13 -07:00
u8_textprep_data.h Replace dead opensolaris.org license link 2022-07-11 14:16:13 -07:00
uberblock.h Replace dead opensolaris.org license link 2022-07-11 14:16:13 -07:00
uberblock_impl.h Replace dead opensolaris.org license link 2022-07-11 14:16:13 -07:00
uio_impl.h Replace dead opensolaris.org license link 2022-07-11 14:16:13 -07:00
unique.h Replace dead opensolaris.org license link 2022-07-11 14:16:13 -07:00
uuid.h Replace dead opensolaris.org license link 2022-07-11 14:16:13 -07:00
vdev.h zed: mark disks as REMOVED when they are removed 2022-09-28 09:48:46 -07:00
vdev_disk.h Replace dead opensolaris.org license link 2022-07-11 14:16:13 -07:00
vdev_draid.h Replace dead opensolaris.org license link 2022-07-11 14:16:13 -07:00
vdev_file.h Replace dead opensolaris.org license link 2022-07-11 14:16:13 -07:00
vdev_impl.h Cleanup: 64-bit kernel module parameters should use fixed width types 2022-10-13 10:03:29 -07:00
vdev_indirect_births.h OpenZFS 7614, 9064 - zfs device evacuation/removal 2018-04-14 12:16:17 -07:00
vdev_indirect_mapping.h OpenZFS 7614, 9064 - zfs device evacuation/removal 2018-04-14 12:16:17 -07:00
vdev_initialize.h Replace dead opensolaris.org license link 2022-07-11 14:16:13 -07:00
vdev_raidz.h Replace dead opensolaris.org license link 2022-07-11 14:16:13 -07:00
vdev_raidz_impl.h Cleanup Raid-Z Typo fixes 2022-09-06 09:43:21 -07:00
vdev_rebuild.h Replace dead opensolaris.org license link 2022-07-11 14:16:13 -07:00
vdev_removal.h Cleanup: Specify unsignedness on things that should not be signed 2022-09-27 16:42:41 -07:00
vdev_trim.h Replace dead opensolaris.org license link 2022-07-11 14:16:13 -07:00
xvattr.h Replace dead opensolaris.org license link 2022-07-11 14:16:13 -07:00
zap.h Replace dead opensolaris.org license link 2022-07-11 14:16:13 -07:00
zap_impl.h Optimize microzaps 2022-10-20 11:57:15 -07:00
zap_leaf.h Replace dead opensolaris.org license link 2022-07-11 14:16:13 -07:00
zcp.h Cleanup: 64-bit kernel module parameters should use fixed width types 2022-10-13 10:03:29 -07:00
zcp_global.h OpenZFS 7431 - ZFS Channel Programs 2018-02-08 15:28:18 -08:00
zcp_iter.h Replace dead opensolaris.org license link 2022-07-11 14:16:13 -07:00
zcp_prop.h OpenZFS 7431 - ZFS Channel Programs 2018-02-08 15:28:18 -08:00
zcp_set.h Support setting user properties in a channel program 2020-02-14 13:41:42 -08:00
zfeature.h Replace dead opensolaris.org license link 2022-07-11 14:16:13 -07:00
zfs_acl.h Support idmapped mount 2022-10-19 11:17:09 -07:00
zfs_bootenv.h zfs label bootenv should store data as nvlist 2020-09-15 15:42:27 -07:00
zfs_chksum.h Replace dead opensolaris.org license link 2022-07-11 14:16:13 -07:00
zfs_context.h Reduce false positives from Static Analyzers 2022-09-30 15:30:12 -07:00
zfs_debug.h Replace dead opensolaris.org license link 2022-07-11 14:16:13 -07:00
zfs_delay.h Replace dead opensolaris.org license link 2022-07-11 14:16:13 -07:00
zfs_file.h Replace dead opensolaris.org license link 2022-07-11 14:16:13 -07:00
zfs_fuid.h Replace dead opensolaris.org license link 2022-07-11 14:16:13 -07:00
zfs_ioctl.h DMU_BACKUP_FEATURE: indicate that bit 28 and 29 are reserved 2022-09-27 16:55:32 -07:00
zfs_ioctl_impl.h Cleanup: 64-bit kernel module parameters should use fixed width types 2022-10-13 10:03:29 -07:00
zfs_onexit.h Replace dead opensolaris.org license link 2022-07-11 14:16:13 -07:00
zfs_project.h Replace dead opensolaris.org license link 2022-07-11 14:16:13 -07:00
zfs_quota.h Replace dead opensolaris.org license link 2022-07-11 14:16:13 -07:00
zfs_racct.h Replace dead opensolaris.org license link 2022-07-11 14:16:13 -07:00
zfs_ratelimit.h Change checksum & IO delay ratelimit values 2018-03-04 17:34:51 -08:00
zfs_refcount.h Replace dead opensolaris.org license link 2022-07-11 14:16:13 -07:00
zfs_rlock.h Replace dead opensolaris.org license link 2022-07-11 14:16:13 -07:00
zfs_sa.h Replace dead opensolaris.org license link 2022-07-11 14:16:13 -07:00
zfs_stat.h Replace dead opensolaris.org license link 2022-07-11 14:16:13 -07:00
zfs_sysfs.h Replace dead opensolaris.org license link 2022-07-11 14:16:13 -07:00
zfs_vfsops.h Replace dead opensolaris.org license link 2022-07-11 14:16:13 -07:00
zfs_vnops.h Replace dead opensolaris.org license link 2022-07-11 14:16:13 -07:00
zfs_znode.h zfs_enter rework 2022-09-16 13:36:47 -07:00
zil.h Add support for per dataset zil stats and use wmsum counters 2022-07-20 17:14:06 -07:00
zil_impl.h Add support for per dataset zil stats and use wmsum counters 2022-07-20 17:14:06 -07:00
zio.h Implement a new type of zfs receive: corrective receive (-c) 2022-07-28 15:52:46 -07:00
zio_checksum.h Fix double const qualifier declarations 2022-09-30 15:34:39 -07:00
zio_compress.h Fix double const qualifier declarations 2022-09-30 15:34:39 -07:00
zio_crypt.h Enable -Wwrite-strings 2022-06-29 14:08:54 -07:00
zio_impl.h Replace dead opensolaris.org license link 2022-07-11 14:16:13 -07:00
zio_priority.h Add device rebuild feature 2020-07-03 11:05:50 -07:00
zrlock.h Replace dead opensolaris.org license link 2022-07-11 14:16:13 -07:00
zthr.h Avoid memory allocations in the ARC eviction thread 2022-01-21 10:28:13 -08:00
zvol.h Replace dead opensolaris.org license link 2022-07-11 14:16:13 -07:00
zvol_impl.h Replace dead opensolaris.org license link 2022-07-11 14:16:13 -07:00