diff options
| author | Darrick J. Wong <darrick.wong@oracle.com> | 2019-02-07 10:37:16 -0800 |
|---|---|---|
| committer | Darrick J. Wong <darrick.wong@oracle.com> | 2019-02-11 16:07:01 -0800 |
| commit | 9b2471797942a5947664818cfe2c6de93b43f37a (patch) | |
| tree | 86d0012e44bc4595f08bdea44f599c156145cf27 /fs/xfs/libxfs | |
| parent | 4664c66c91a14019551b9ba8b2998fa3b5f69499 (diff) | |
xfs: cache unlinked pointers in an rhashtable
Use a rhashtable to cache the unlinked list incore. This should speed
up unlinked processing considerably when there are a lot of inodes on
the unlinked list because iunlink_remove no longer has to traverse an
entire bucket list to find which inode points to the one being removed.
The incore list structure records "X.next_unlinked = Y" relations, with
the rhashtable using Y to index the records. This makes finding the
inode X that points to a inode Y very quick. If our cache fails to find
anything we can always fall back on the old method.
FWIW this drastically reduces the amount of time it takes to remove
inodes from the unlinked list. I wrote a program to open a lot of
O_TMPFILE files and then close them in the same order, which takes
a very long time if we have to traverse the unlinked lists. With the
ptach, I see:
+ /d/t/tmpfile/tmpfile
Opened 193531 files in 6.33s.
Closed 193531 files in 5.86s
real 0m12.192s
user 0m0.064s
sys 0m11.619s
+ cd /
+ umount /mnt
real 0m0.050s
user 0m0.004s
sys 0m0.030s
And without the patch:
+ /d/t/tmpfile/tmpfile
Opened 193588 files in 6.35s.
Closed 193588 files in 751.61s
real 12m38.853s
user 0m0.084s
sys 12m34.470s
+ cd /
+ umount /mnt
real 0m0.086s
user 0m0.000s
sys 0m0.060s
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Diffstat (limited to 'fs/xfs/libxfs')
| -rw-r--r-- | fs/xfs/libxfs/xfs_errortag.h | 4 |
1 files changed, 3 insertions, 1 deletions
diff --git a/fs/xfs/libxfs/xfs_errortag.h b/fs/xfs/libxfs/xfs_errortag.h index 66077a105cbb..79e6c4fb1d8a 100644 --- a/fs/xfs/libxfs/xfs_errortag.h +++ b/fs/xfs/libxfs/xfs_errortag.h @@ -54,7 +54,8 @@ #define XFS_ERRTAG_BUF_LRU_REF 31 #define XFS_ERRTAG_FORCE_SCRUB_REPAIR 32 #define XFS_ERRTAG_FORCE_SUMMARY_RECALC 33 -#define XFS_ERRTAG_MAX 34 +#define XFS_ERRTAG_IUNLINK_FALLBACK 34 +#define XFS_ERRTAG_MAX 35 /* * Random factors for above tags, 1 means always, 2 means 1/2 time, etc. @@ -93,5 +94,6 @@ #define XFS_RANDOM_BUF_LRU_REF 2 #define XFS_RANDOM_FORCE_SCRUB_REPAIR 1 #define XFS_RANDOM_FORCE_SUMMARY_RECALC 1 +#define XFS_RANDOM_IUNLINK_FALLBACK (XFS_RANDOM_DEFAULT/10) #endif /* __XFS_ERRORTAG_H_ */ |