freebsd-nq/module/zfs
Brian Behlendorf 78d7a5d780 Write dirty inodes on close
When the property atime=on is set operations which only access
and inode do cause an atime update.  However, it turns out that
dirty inodes with updated atimes are only written to disk when
the inodes get evicted from the cache.  Somewhat surprisingly
the source suggests that this isn't a ZoL specific issue.

This behavior may in part explain why zfs's reclaim logic has
been observed to be slow.  When reclaiming inodes its likely
that they have a dirty atime which will force a write to disk.

Obviously we don't want to force a write to disk for every
atime update, these needs to be batched.  The right way to
do this is to fully implement the .dirty_inode and .write_inode
callbacks.  However, to do that right requires proper unification
of some fields in the znode/inode.  Then we could just mark the
inode dirty and leave it to the VFS to call .write_inode
periodically.

Until that work gets done we have to settle for some middle
ground.  The simplest and safest thing we can do for now is
to write the dirty inode on last close.  This should prevent
the majority of inodes in the cache from having dirty atimes
and not drastically increase the number of writes.

Some rudimentally testing to show how long it takes to drop
500,000 inodes from the cache shows promising results.  This
is as expected because we're no longer do lots of IO as part
of the eviction, it was done earlier during the close.

w/out patch: ~30s to drop 500,000 inodes with drop_caches.
with patch:  ~3s to drop 500,000 inodes with drop_caches.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
2013-08-07 16:11:19 -07:00
..
arc.c Remove b_thawed from arc_buf_hdr_t 2013-08-01 09:48:07 -07:00
bplist.c Switch KM_SLEEP to KM_PUSHPAGE 2012-08-27 12:01:37 -07:00
bpobj.c Illumos #3006 2013-06-19 15:14:10 -07:00
bptree.c Illumos #3498 panic in arc_read() 2013-07-02 13:34:31 -07:00
dbuf.c Illumos #3498 panic in arc_read() 2013-07-02 13:34:31 -07:00
ddt_zap.c Add ddt_object_count() error handling 2012-10-29 08:57:45 -07:00
ddt.c Fix incorrect assertions in ddt_phys_decref and ddt_sync_entry 2013-05-06 14:10:55 -07:00
dmu_diff.c Illumos #3498 panic in arc_read() 2013-07-02 13:34:31 -07:00
dmu_object.c Add linux kernel module support 2010-08-31 13:41:58 -07:00
dmu_objset.c Illumos #3498 panic in arc_read() 2013-07-02 13:34:31 -07:00
dmu_send.c Illumos #3498 panic in arc_read() 2013-07-02 13:34:31 -07:00
dmu_traverse.c Illumos #3498 panic in arc_read() 2013-07-02 13:34:31 -07:00
dmu_tx.c dmu_tx: Fix possible NULL pointer dereference 2013-08-01 09:48:07 -07:00
dmu_zfetch.c Switch KM_SLEEP to KM_PUSHPAGE 2012-08-27 12:01:37 -07:00
dmu.c Export additional dmu symbols 2013-08-01 09:48:07 -07:00
dnode_sync.c Illumos #3006 2013-06-19 15:14:10 -07:00
dnode.c Illumos #3006 2013-06-19 15:14:10 -07:00
dsl_dataset.c Illumos #3498 panic in arc_read() 2013-07-02 13:34:31 -07:00
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 Illumos #3006 2013-06-19 15:14:10 -07:00
dsl_pool.c Add new kstat for monitoring time in dmu_tx_assign 2013-07-11 13:53:44 -07:00
dsl_prop.c Switch KM_SLEEP to KM_PUSHPAGE 2012-09-17 11:22:23 -07:00
dsl_scan.c Illumos #3498 panic in arc_read() 2013-07-02 13:34:31 -07:00
dsl_synctask.c Illumos #3006 2013-06-19 15:14:10 -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 #3552, #3564 2013-06-19 16:22:39 -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 Add zfs_autoimport_disable tunable 2013-07-09 10:11:19 -07:00
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 Call zvol_create_minors() in spa_open_common() when initializing pool 2013-07-03 09:22:44 -07:00
space_map.c Illumos #3552, #3564 2013-06-19 16:22:39 -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 Use GFP_NOIO in vdev_disk_io_flush() 2013-07-10 14:12:21 -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 Improve N-way mirror performance 2013-07-11 13:53:50 -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 #3006 2013-06-19 15:14:10 -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 Illumos #3552, #3564 2013-06-19 16:22:39 -07:00
zap_leaf.c Switch KM_SLEEP to KM_PUSHPAGE 2012-09-05 08:44:58 -07:00
zap_micro.c Illumos #3006 2013-06-19 15:14:10 -07:00
zap.c Illumos #3006 2013-06-19 15:14:10 -07:00
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 Fix zfsctl_expire_snapshot() deadlock 2013-07-12 10:06:53 -07:00
zfs_debug.c Illumos #3006 2013-06-19 15:14:10 -07:00
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 Call zvol_create_minors() in spa_open_common() when initializing pool 2013-07-03 09:22:44 -07:00
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 Illumos #3006 2013-06-19 15:14:10 -07:00
zfs_sa.c Revert "Use SA_HDL_PRIVATE for SA xattrs" 2012-08-25 09:25:56 -07:00
zfs_vfsops.c Fix read-only pool hang on unmount 2013-07-17 09:22:23 -07:00
zfs_vnops.c Add SEEK_DATA/SEEK_HOLE to lseek()/llseek() 2013-07-02 09:24:43 -07:00
zfs_znode.c Illumos #3006 2013-06-19 15:14:10 -07:00
zil.c Illumos #3498 panic in arc_read() 2013-07-02 13:34:31 -07:00
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 Remove zio_alloc_arena 2013-08-01 09:48:06 -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 Write dirty inodes on close 2013-08-07 16:11:19 -07:00
zpl_inode.c Add explicit MAXNAMELEN check 2013-02-12 10:27:39 -08:00
zpl_super.c Fix arc_adapt() spinning in iterate_supers_type() 2013-07-17 09:28:06 -07:00
zpl_xattr.c Only check directory xattr on ENOENT 2013-05-10 12:24:56 -07:00
zrlock.c Export ZFS symbols needed by Lustre. 2010-09-17 16:24:15 -07:00
zvol.c 3.10 API change: block_device_operations->release() returns void 2013-07-08 15:41:57 -07:00