aboutsummaryrefslogtreecommitdiff
path: root/Documentation/ABI
diff options
context:
space:
mode:
Diffstat (limited to 'Documentation/ABI')
-rw-r--r--Documentation/ABI/testing/sysfs-class-bdi46
1 files changed, 46 insertions, 0 deletions
diff --git a/Documentation/ABI/testing/sysfs-class-bdi b/Documentation/ABI/testing/sysfs-class-bdi
new file mode 100644
index 00000000000..b800cdda40b
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-class-bdi
@@ -0,0 +1,46 @@
+What: /sys/class/bdi/<bdi>/
+Date: January 2008
+Contact: Peter Zijlstra <a.p.zijlstra@chello.nl>
+Description:
+
+Provide a place in sysfs for the backing_dev_info object.
+This allows us to see and set the various BDI specific variables.
+
+The <bdi> identifier can be either of the following:
+
+MAJOR:MINOR
+
+ Device number for block devices, or value of st_dev on
+ non-block filesystems which provide their own BDI, such as NFS
+ and FUSE.
+
+default
+
+ The default backing dev, used for non-block device backed
+ filesystems which do not provide their own BDI.
+
+Files under /sys/class/bdi/<bdi>/
+---------------------------------
+
+read_ahead_kb (read-write)
+
+ Size of the read-ahead window in kilobytes
+
+reclaimable_kb (read-only)
+
+ Reclaimable (dirty or unstable) memory destined for writeback
+ to this device
+
+writeback_kb (read-only)
+
+ Memory currently under writeback to this device
+
+dirty_kb (read-only)
+
+ Global threshold for reclaimable + writeback memory
+
+bdi_dirty_kb (read-only)
+
+ Current threshold on this BDI for reclaimable + writeback
+ memory
+