diff options
| author | Jeff Layton <jlayton@redhat.com> | 2011-03-25 16:25:57 -0400 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@suse.de> | 2011-04-21 14:32:20 -0700 |
| commit | 591c80b5a9a9331a9b2a6d1b7d9b97d3445107c9 (patch) | |
| tree | ad013ed7abb0b7eadb9e456a90a95c0bccbdf41a /fs | |
| parent | 7cb41edf395b70a6e48162382c5577967ce92bbf (diff) | |
cifs: set ra_pages in backing_dev_info
commit 2b6c26a0a62cc0bab0ad487533d5581d7c293fef upstream.
Commit 522440ed made cifs set backing_dev_info on the mapping attached
to new inodes. This change caused a fairly significant read performance
regression, as cifs started doing page-sized reads exclusively.
By virtue of the fact that they're allocated as part of cifs_sb_info by
kzalloc, the ra_pages on cifs BDIs get set to 0, which prevents any
readahead. This forces the normal read codepaths to use readpage instead
of readpages causing a four-fold increase in the number of read calls
with the default rsize.
Fix it by setting ra_pages in the BDI to the same value as that in the
default_backing_dev_info.
Fixes https://bugzilla.kernel.org/show_bug.cgi?id=31662
Reported-and-Tested-by: Till <till2.schaefer@uni-dortmund.de>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Diffstat (limited to 'fs')
| -rw-r--r-- | fs/cifs/cifsfs.c | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/fs/cifs/cifsfs.c b/fs/cifs/cifsfs.c index f2970136d17..c0def4f5602 100644 --- a/fs/cifs/cifsfs.c +++ b/fs/cifs/cifsfs.c @@ -127,6 +127,7 @@ cifs_read_super(struct super_block *sb, void *data, kfree(cifs_sb); return rc; } + cifs_sb->bdi.ra_pages = default_backing_dev_info.ra_pages; #ifdef CONFIG_CIFS_DFS_UPCALL /* copy mount params to sb for use in submounts */ |