summaryrefslogtreecommitdiff
path: root/Documentation/filesystems/caching
diff options
context:
space:
mode:
authorDavid Howells <dhowells@redhat.com>2009-04-03 16:42:37 +0100
committerDavid Howells <dhowells@redhat.com>2009-04-03 16:42:37 +0100
commit7394daa8c61dfda4baa687f133748fa0b599b017 (patch)
tree32d2c55ed60596918ec62ce6ecca186337bf4660 /Documentation/filesystems/caching
parent06b3db1b9bccdc8c2c743122a89745279e5ecc46 (diff)
FS-Cache: Add use of /proc and presentation of statistics
Make FS-Cache create its /proc interface and present various statistical information through it. Also provide the functions for updating this information. These features are enabled by: CONFIG_FSCACHE_PROC CONFIG_FSCACHE_STATS CONFIG_FSCACHE_HISTOGRAM The /proc directory for FS-Cache is also exported so that caching modules can add their own statistics there too. The FS-Cache module is loadable at this point, and the statistics files can be examined by userspace: cat /proc/fs/fscache/stats cat /proc/fs/fscache/histogram Signed-off-by: David Howells <dhowells@redhat.com> Acked-by: Steve Dickson <steved@redhat.com> Acked-by: Trond Myklebust <Trond.Myklebust@netapp.com> Acked-by: Al Viro <viro@zeniv.linux.org.uk> Tested-by: Daire Byrne <Daire.Byrne@framestore.com>
Diffstat (limited to 'Documentation/filesystems/caching')
-rw-r--r--Documentation/filesystems/caching/backend-api.txt6
-rw-r--r--Documentation/filesystems/caching/fscache.txt12
2 files changed, 5 insertions, 13 deletions
diff --git a/Documentation/filesystems/caching/backend-api.txt b/Documentation/filesystems/caching/backend-api.txt
index 17723053aa91..382d52cdaf2d 100644
--- a/Documentation/filesystems/caching/backend-api.txt
+++ b/Documentation/filesystems/caching/backend-api.txt
@@ -100,12 +100,6 @@ A sysfs directory called /sys/fs/fscache/<cachetag>/ is created if CONFIG_SYSFS
is enabled. This is accessible through the kobject struct fscache_cache::kobj
and is for use by the cache as it sees fit.
-The cache driver may create itself a directory named for the cache type in the
-/proc/fs/fscache/ directory. This is available if CONFIG_FSCACHE_PROC is
-enabled and is accessible through:
-
- struct proc_dir_entry *proc_fscache;
-
========================
RELEVANT DATA STRUCTURES
diff --git a/Documentation/filesystems/caching/fscache.txt b/Documentation/filesystems/caching/fscache.txt
index a759d916273e..0a751f3c2c70 100644
--- a/Documentation/filesystems/caching/fscache.txt
+++ b/Documentation/filesystems/caching/fscache.txt
@@ -195,7 +195,6 @@ STATISTICAL INFORMATION
If FS-Cache is compiled with the following options enabled:
- CONFIG_FSCACHE_PROC=y (implied by the following two)
CONFIG_FSCACHE_STATS=y
CONFIG_FSCACHE_HISTOGRAM=y
@@ -275,7 +274,7 @@ proc files.
(*) /proc/fs/fscache/histogram
cat /proc/fs/fscache/histogram
- +HZ +TIME OBJ INST OP RUNS OBJ RUNS RETRV DLY RETRIEVLS
+ JIFS SECS OBJ INST OP RUNS OBJ RUNS RETRV DLY RETRIEVLS
===== ===== ========= ========= ========= ========= =========
This shows the breakdown of the number of times each amount of time
@@ -291,16 +290,16 @@ proc files.
RETRIEVLS Time between beginning and end of a retrieval
Each row shows the number of events that took a particular range of times.
- Each step is 1 jiffy in size. The +HZ column indicates the particular
- jiffy range covered, and the +TIME field the equivalent number of seconds.
+ Each step is 1 jiffy in size. The JIFS column indicates the particular
+ jiffy range covered, and the SECS field the equivalent number of seconds.
=========
DEBUGGING
=========
-The FS-Cache facility can have runtime debugging enabled by adjusting the value
-in:
+If CONFIG_FSCACHE_DEBUG is enabled, the FS-Cache facility can have runtime
+debugging enabled by adjusting the value in:
/sys/module/fscache/parameters/debug
@@ -327,4 +326,3 @@ the control file. For example:
echo $((1|8|64)) >/sys/module/fscache/parameters/debug
will turn on all function entry debugging.
-