diff options
| author | Bob Peterson <rpeterso@redhat.com> | 2012-10-19 08:32:51 -0400 |
|---|---|---|
| committer | Steven Whitehouse <swhiteho@redhat.com> | 2012-11-07 13:31:36 +0000 |
| commit | a68a0a352a0209467268dfddffe02db08b97ddb4 (patch) | |
| tree | d307e08ac5f985d1e93ebf5fa0f18255a4610bd6 /fs/gfs2/ops_fstype.c | |
| parent | 8eae1ca0034cce78a24738087a32adb1ddb66aa7 (diff) | |
GFS2: Speed up gfs2_rbm_from_block
This patch is a rewrite of function gfs2_rbm_from_block. Rather than
looping to find the right bitmap, the code now does a few simple
math calculations.
I compared the performance of both algorithms side by side and the new
algorithm is noticeably faster. Sample instrumentation output from a
"fast" machine:
5 million calls: millisec spent: Orig: 166 New: 113
5 million calls: millisec spent: Orig: 189 New: 114
In addition, I ran postmark (on a somewhat slowr CPU) before the after
the new algorithm was put in place and postmark showed a decent
improvement:
Before the new algorithm:
-------------------------
Time:
645 seconds total
584 seconds of transactions (171 per second)
Files:
150087 created (232 per second)
Creation alone: 100000 files (2083 per second)
Mixed with transactions: 50087 files (85 per second)
49995 read (85 per second)
49991 appended (85 per second)
150087 deleted (232 per second)
Deletion alone: 100174 files (7705 per second)
Mixed with transactions: 49913 files (85 per second)
Data:
273.42 megabytes read (434.08 kilobytes per second)
852.13 megabytes written (1.32 megabytes per second)
With the new algorithm:
-----------------------
Time:
599 seconds total
530 seconds of transactions (188 per second)
Files:
150087 created (250 per second)
Creation alone: 100000 files (1886 per second)
Mixed with transactions: 50087 files (94 per second)
49995 read (94 per second)
49991 appended (94 per second)
150087 deleted (250 per second)
Deletion alone: 100174 files (6260 per second)
Mixed with transactions: 49913 files (94 per second)
Data:
273.42 megabytes read (467.42 kilobytes per second)
852.13 megabytes written (1.42 megabytes per second)
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Diffstat (limited to 'fs/gfs2/ops_fstype.c')
| -rw-r--r-- | fs/gfs2/ops_fstype.c | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/fs/gfs2/ops_fstype.c b/fs/gfs2/ops_fstype.c index e443966c8106..0e3554edb8f2 100644 --- a/fs/gfs2/ops_fstype.c +++ b/fs/gfs2/ops_fstype.c @@ -278,6 +278,9 @@ static int gfs2_read_sb(struct gfs2_sbd *sdp, int silent) sdp->sd_qc_per_block = (sdp->sd_sb.sb_bsize - sizeof(struct gfs2_meta_header)) / sizeof(struct gfs2_quota_change); + sdp->sd_blocks_per_bitmap = (sdp->sd_sb.sb_bsize - + sizeof(struct gfs2_meta_header)) + * GFS2_NBBY; /* not the rgrp bitmap, subsequent bitmaps only */ /* Compute maximum reservation required to add a entry to a directory */ |