Adam Leventhal 7ef5e54e2e Illumos #3581 spa_zio_taskq[ZIO_TYPE_FREE][ZIO_TASKQ_ISSUE]->tq_lock contention ... 3581 spa_zio_taskq[ZIO_TYPE_FREE][ZIO_TASKQ_ISSUE]->tq_lock is piping hot Reviewed by: Matthew Ahrens <mahrens@delphix.com> Reviewed by: George Wilson <george.wilson@delphix.com> Reviewed by: Christopher Siden <christopher.siden@delphix.com> Reviewed by: Gordon Ross <gordon.ross@nexenta.com> Approved by: Richard Lowe <richlowe@richlowe.net> References: illumos/illumos-gate@ec94d32 https://illumos.org/issues/3581 Notes for Linux port: Earlier commit 08d08eb reduced contention on this taskq lock by simply reducing the number of z_fr_iss threads from 100 to one-per-CPU. We also optimized the taskq implementation in zfsonlinux/spl@3c6ed54. These changes significantly improved unlink performance to acceptable levels. This patch further reduces time spent spinning on this lock by randomly dispatching the work items over multiple independent task queues. The Illumos ZFS developers stated that this lock contention only arose after "3329 spa_sync() spends 10-20% of its time in spa_free_sync_cb()" was landed. It's not clear if 3329 affects the Linux port or not. I didn't see spa_free_sync_cb() show up in oprofile sessions while unlinking large files, but I may just not have used the right test case. I tested unlinking a 1 TB of data with and without the patch and didn't observe a meaningful difference in elapsed time. However, oprofile showed that the percent time spent in taskq_thread() was reduced from about 16% to about 5%. Aside from a possible slight performance benefit this may be worth landing if only for the sake of maintaining consistency with upstream. Ported-by: Ned Bass <bass6@llnl.gov> Closes #1327		2013-05-06 14:05:37 -07:00
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arc.c	Constify structures containing function pointers	2013-03-04 08:49:32 -08:00
bplist.c	Switch KM_SLEEP to KM_PUSHPAGE	2012-08-27 12:01:37 -07:00
bpobj.c	Illumos #3104: eliminate empty bpobjs	2013-01-08 10:35:43 -08:00
bptree.c	Illumos #2619 and #2747	2013-01-08 10:35:35 -08:00
dbuf.c	Illumos #3145, #3212	2013-01-08 10:35:44 -08:00
ddt_zap.c	Add ddt_object_count() error handling	2012-10-29 08:57:45 -07:00
ddt.c	Add zio_ddt_free()+ddt_phys_decref() error handling	2013-03-19 13:01:01 -07:00
dmu_diff.c	Update to onnv_147	2010-08-26 14:24:34 -07:00
dmu_object.c	Add linux kernel module support	2010-08-31 13:41:58 -07:00
dmu_objset.c	Switch KM_SLEEP to KM_PUSHPAGE	2013-02-06 11:19:58 -08:00
dmu_send.c	Cast 'zfs bad bloc' to ULL for x86	2013-02-04 16:39:08 -08:00
dmu_traverse.c	Illumos #2619 and #2747	2013-01-08 10:35:35 -08:00
dmu_tx.c	Illumos #3422, #3425	2013-04-12 09:01:36 -07:00
dmu_zfetch.c	Switch KM_SLEEP to KM_PUSHPAGE	2012-08-27 12:01:37 -07:00
dmu.c	Illumos #3086: unnecessarily setting DS_FLAG_INCONSISTENT on async	2013-01-08 10:35:43 -08:00
dnode_sync.c	Illumos #2619 and #2747	2013-01-08 10:35:35 -08:00
dnode.c	Illumos #2619 and #2747	2013-01-08 10:35:35 -08:00
dsl_dataset.c	Use dsl_dataset_snap_lookup()	2013-01-25 15:07:40 -08:00
dsl_deadlist.c	Illumos #3104: eliminate empty bpobjs	2013-01-08 10:35:43 -08:00
dsl_deleg.c	Illumos #2619 and #2747	2013-01-08 10:35:35 -08:00
dsl_dir.c	Switch KM_SLEEP to KM_PUSHPAGE	2013-02-06 11:19:58 -08:00
dsl_pool.c	Fix txg_quiesce thread deadlock	2013-04-26 14:42:36 -07:00
dsl_prop.c	Switch KM_SLEEP to KM_PUSHPAGE	2012-09-17 11:22:23 -07:00
dsl_scan.c	Illumos #2619 and #2747	2013-01-08 10:35:35 -08:00
dsl_synctask.c	Add linux kernel module support	2010-08-31 13:41:58 -07:00
fm.c	Condition variable usage, zevent_cv	2012-10-15 16:01:54 -07:00
gzip.c	Fix zmod.h usage in userspace	2010-08-31 08:38:46 -07:00
lz4.c	Linux 3.9 compat: Undefine GCC_VERSION	2013-03-06 15:48:48 -08:00
lzjb.c	Switch KM_SLEEP to KM_PUSHPAGE	2012-08-27 12:01:37 -07:00
Makefile.in	Illumos #3035 LZ4 compression support in ZFS and GRUB	2013-01-29 09:28:20 -08:00
metaslab.c	Illumos #3329, #3330, #3331, #3335	2013-05-06 12:39:34 -07:00
refcount.c	Switch KM_SLEEP to KM_PUSHPAGE	2012-08-27 12:01:37 -07:00
rrwlock.c	Enable rrwlock.c compilation	2010-12-07 16:05:25 -08:00
sa.c	Constify structures containing function pointers	2013-03-04 08:49:32 -08:00
sha256.c	Add linux sha2 support	2010-08-31 13:41:59 -07:00
spa_boot.c	Add linux kernel module support	2010-08-31 13:41:58 -07:00
spa_config.c	Illumos #2619 and #2747	2013-01-08 10:35:35 -08:00
spa_errlog.c	Add linux kernel module support	2010-08-31 13:41:58 -07:00
spa_history.c	Switch KM_SLEEP to KM_PUSHPAGE	2012-08-27 12:01:37 -07:00
spa_misc.c	Illumos #3329, #3330, #3331, #3335	2013-05-06 12:39:34 -07:00
spa.c	Illumos #3581 spa_zio_taskq[ZIO_TYPE_FREE][ZIO_TASKQ_ISSUE]->tq_lock contention	2013-05-06 14:05:37 -07:00
space_map.c	Illumos #3329, #3330, #3331, #3335	2013-05-06 12:39:34 -07:00
txg.c	Fix txg_quiesce thread deadlock	2013-04-26 14:42:36 -07:00
uberblock.c	Update core ZFS code from build 121 to build 141.	2010-05-28 13:45:14 -07:00
unique.c	Switch KM_SLEEP to KM_PUSHPAGE	2012-08-27 12:01:37 -07:00
vdev_cache.c	Switch KM_SLEEP to KM_PUSHPAGE	2012-08-27 12:01:37 -07:00
vdev_disk.c	3246 ZFS I/O deadman thread	2013-05-01 17:05:52 -07:00
vdev_file.c	Illumos #3581 spa_zio_taskq[ZIO_TYPE_FREE][ZIO_TASKQ_ISSUE]->tq_lock contention	2013-05-06 14:05:37 -07:00
vdev_label.c	Illumos #3090 and #3102	2013-01-08 10:35:42 -08:00
vdev_mirror.c	Illumos #1948: zpool list should show more detailed pool info	2012-09-19 13:39:05 -07:00
vdev_missing.c	Illumos #1948: zpool list should show more detailed pool info	2012-09-19 13:39:05 -07:00
vdev_queue.c	3246 ZFS I/O deadman thread	2013-05-01 17:05:52 -07:00
vdev_raidz.c	Illumos #1948: zpool list should show more detailed pool info	2012-09-19 13:39:05 -07:00
vdev_root.c	Illumos #1948: zpool list should show more detailed pool info	2012-09-19 13:39:05 -07:00
vdev.c	3246 ZFS I/O deadman thread	2013-05-01 17:05:52 -07:00
zap_leaf.c	Switch KM_SLEEP to KM_PUSHPAGE	2012-09-05 08:44:58 -07:00
zap_micro.c	Illumos #2619 and #2747	2013-01-08 10:35:35 -08:00
zap.c	fzap_cursor_move_to_key() should drop l_rwlock	2013-01-23 16:31:16 -08:00
zfeature_common.c	Illumos #3035 LZ4 compression support in ZFS and GRUB	2013-01-29 09:28:20 -08:00
zfeature.c	Illumos #3104: eliminate empty bpobjs	2013-01-08 10:35:43 -08:00
zfs_acl.c	Avoid gcc -Werror=maybe-uninitialized warnings	2013-01-28 09:10:29 -08:00
zfs_byteswap.c	Add linux kernel module support	2010-08-31 13:41:58 -07:00
zfs_ctldir.c	Use dsl_dataset_snap_lookup()	2013-01-25 15:07:40 -08:00
zfs_debug.c	Use spl_debug_* helpers	2012-02-09 16:37:48 -08:00
zfs_dir.c	Trivial spelling fix	2013-04-19 15:43:16 -07:00
zfs_fm.c	3246 ZFS I/O deadman thread	2013-05-01 17:05:52 -07:00
zfs_fuid.c	Drop HAVE_XVATTR macros	2011-03-02 11:44:34 -08:00
zfs_ioctl.c	Add snapdev=[hidden|visible] dataset property	2013-03-05 12:37:54 -08:00
zfs_log.c	Revert "Remove TSD zfs_fsyncer_key"	2012-12-20 09:56:28 -08:00
zfs_onexit.c	Add linux kernel device support	2010-08-31 13:41:50 -07:00
zfs_replay.c	Constify structures containing function pointers	2013-03-04 08:49:32 -08:00
zfs_rlock.c	Switch KM_SLEEP to KM_PUSHPAGE	2012-12-10 09:44:45 -08:00
zfs_sa.c	Revert "Use SA_HDL_PRIVATE for SA xattrs"	2012-08-25 09:25:56 -07:00
zfs_vfsops.c	Use sb->s_d_op default dentry operations	2013-01-18 15:04:23 -08:00
zfs_vnops.c	Revert "Remove TSD zfs_fsyncer_key"	2012-12-20 09:56:28 -08:00
zfs_znode.c	Fix 'zfs rollback' on mounted file systems	2013-01-17 09:51:20 -08:00
zil.c	Constify structures containing function pointers	2013-03-04 08:49:32 -08:00
zio_checksum.c	Update core ZFS code from build 121 to build 141.	2010-05-28 13:45:14 -07:00
zio_compress.c	Illumos #3035 LZ4 compression support in ZFS and GRUB	2013-01-29 09:28:20 -08:00
zio_inject.c	3246 ZFS I/O deadman thread	2013-05-01 17:05:52 -07:00
zio.c	Illumos #3581 spa_zio_taskq[ZIO_TYPE_FREE][ZIO_TASKQ_ISSUE]->tq_lock contention	2013-05-06 14:05:37 -07:00
zle.c	Update core ZFS code from build 121 to build 141.	2010-05-28 13:45:14 -07:00
zpl_ctldir.c	Add d_clear_d_op() compatibility	2013-01-23 16:33:29 -08:00
zpl_export.c	Implement .commit_metadata hook for NFS export	2012-10-03 10:49:45 -07:00
zpl_file.c	Remove .readdir from zpl_file_operations table	2013-04-19 15:36:47 -07:00
zpl_inode.c	Add explicit MAXNAMELEN check	2013-02-12 10:27:39 -08:00
zpl_super.c	Update SAs when an inode is dirtied	2012-12-14 12:18:54 -08:00
zpl_xattr.c	Correctly return ERANGE in getxattr(2)	2013-04-24 12:35:04 -07:00
zrlock.c	Export ZFS symbols needed by Lustre.	2010-09-17 16:24:15 -07:00
zvol.c	Add snapdev=[hidden|visible] dataset property	2013-03-05 12:37:54 -08:00