path: root/fs/9p/v9fs.h
diff options
authorEric Van Hensbergen <ericvh@gmail.com>2007-02-11 13:21:39 -0600
committerEric Van Hensbergen <ericvh@gmail.com>2007-02-18 10:16:10 -0600
commite03abc0c963a31cb07dfbc07c7d85d75e0d13cf4 (patch)
tree1840001bde4a7f9f01d39dd09baf7d7b04e95706 /fs/9p/v9fs.h
parent2c0463a9ae8751547c39302aeb31c6cef16b5df4 (diff)
9p: implement optional loose read cache
While cacheing is generally frowned upon in the 9p world, it has its place -- particularly in situations where the remote file system is exclusive and/or read-only. The vacfs views of venti content addressable store are a real-world instance of such a situation. To facilitate higher performance for these workloads (and eventually use the fscache patches), we have enabled a "loose" cache mode which does not attempt to maintain any form of consistency on the page-cache or dcache. This results in over two orders of magnitude performance improvement for cacheable block reads in the Bonnie benchmark. The more aggressive use of the dcache also seems to improve metadata operational performance. Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
Diffstat (limited to 'fs/9p/v9fs.h')
1 files changed, 8 insertions, 1 deletions
diff --git a/fs/9p/v9fs.h b/fs/9p/v9fs.h
index c134d104cb2..820bf5ca35d 100644
--- a/fs/9p/v9fs.h
+++ b/fs/9p/v9fs.h
@@ -47,7 +47,7 @@ struct v9fs_session_info {
unsigned int afid; /* authentication fid */
unsigned int rfdno; /* read file descriptor number */
unsigned int wfdno; /* write file descriptor number */
+ unsigned int cache; /* cache mode */
char *name; /* user name to mount as */
char *remotename; /* name of remote hierarchy being mounted */
@@ -73,6 +73,13 @@ enum {
+/* possible values of ->cache */
+/* eventually support loose, tight, time, session, default always none */
+enum {
+ CACHE_NONE, /* default */
+ CACHE_LOOSE, /* no consistency */
extern struct dentry *v9fs_debugfs_root;
int v9fs_session_init(struct v9fs_session_info *, const char *, char *);