linux/include
Zheng Liu eb68d0e2fc ext4: track extent status tree shrinker delay statictics
This commit adds some statictics in extent status tree shrinker.  The
purpose to add these is that we want to collect more details when we
encounter a stall caused by extent status tree shrinker.  Here we count
the following statictics:
  stats:
    the number of all objects on all extent status trees
    the number of reclaimable objects on lru list
    cache hits/misses
    the last sorted interval
    the number of inodes on lru list
  average:
    scan time for shrinking some objects
    the number of shrunk objects
  maximum:
    the inode that has max nr. of objects on lru list
    the maximum scan time for shrinking some objects

The output looks like below:
  $ cat /proc/fs/ext4/sda1/es_shrinker_info
  stats:
    28228 objects
    6341 reclaimable objects
    5281/631 cache hits/misses
    586 ms last sorted interval
    250 inodes on lru list
  average:
    153 us scan time
    128 shrunk objects
  maximum:
    255 inode (255 objects, 198 reclaimable)
    125723 us max scan time

If the lru list has never been sorted, the following line will not be
printed:
    586ms last sorted interval
If there is an empty lru list, the following lines also will not be
printed:
    250 inodes on lru list
  ...
  maximum:
    255 inode (255 objects, 198 reclaimable)
    0 us max scan time

Meanwhile in this commit a new trace point is defined to print some
details in __ext4_es_shrink().

Cc: Andreas Dilger <adilger.kernel@dilger.ca>
Cc: Jan Kara <jack@suse.cz>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Zheng Liu <wenqing.lz@taobao.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2014-09-01 22:26:49 -04:00
..
acpi
asm-generic This is the bulk of GPIO changes for the v3.17 development 2014-08-08 18:00:35 -07:00
clocksource
crypto
drm drm/radeon: add additional SI pci ids 2014-08-22 10:47:59 -04:00
dt-bindings Merge branch 'for-linus' of git://git.infradead.org/users/vkoul/slave-dma 2014-08-11 07:14:01 -07:00
keys
kvm
linux Ext4 bug fixes for 3.17, to provide better handling of memory 2014-08-29 11:52:46 -07:00
math-emu
media
memory
misc
net tcp: don't allow syn packets without timestamps to pass tcp_tw_recycle logic 2014-08-14 14:38:54 -07:00
pcmcia
ras
rdma Merge branches 'core', 'cxgb4', 'ipoib', 'iser', 'iwcm', 'mad', 'misc', 'mlx4', 'mlx5', 'ocrdma' and 'srp' into for-next 2014-08-14 08:58:04 -07:00
rxrpc
scsi SCSI misc on 20140815 2014-08-15 18:28:58 -06:00
soc/tegra
sound
target
trace ext4: track extent status tree shrinker delay statictics 2014-09-01 22:26:49 -04:00
uapi Merge branch 'drm-fixes' of git://people.freedesktop.org/~airlied/linux 2014-08-24 15:48:12 -07:00
video fbdev changes for 3.17 2014-08-08 18:09:33 -07:00
xen
Kbuild