* [PATCH v2] doc: add description to dirtytime_expire_seconds
@ 2018-06-18 23:59 Yang Shi
0 siblings, 0 replies; only message in thread
From: Yang Shi @ 2018-06-18 23:59 UTC (permalink / raw)
To: tytso, nborisov, corbet, akpm; +Cc: linux-fsdevel, linux-mm, linux-kernel
commit 1efff914afac8a965ad63817ecf8861a927c2ace ("fs: add
dirtytime_expire_seconds sysctl") introduced dirtytime_expire_seconds
knob, but there is not description about it in
Documentation/sysctl/vm.txt.
Add the description for it.
Cc: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Yang Shi <yang.shi@linux.alibaba.com>
---
v1 --> v2: Rephrased the description per Nikolay Borisov's comment
I didn't dig into the old review discussion about why the description
was not added at the first place. I'm supposed every knob under /proc/sys
should have a brief description.
Documentation/sysctl/vm.txt | 13 +++++++++++++
1 file changed, 13 insertions(+)
diff --git a/Documentation/sysctl/vm.txt b/Documentation/sysctl/vm.txt
index 17256f2..b078baf 100644
--- a/Documentation/sysctl/vm.txt
+++ b/Documentation/sysctl/vm.txt
@@ -27,6 +27,7 @@ Currently, these files are in /proc/sys/vm:
- dirty_bytes
- dirty_expire_centisecs
- dirty_ratio
+- dirtytime_expire_seconds
- dirty_writeback_centisecs
- drop_caches
- extfrag_threshold
@@ -178,6 +179,18 @@ The total available memory is not equal to total system memory.
==============================================================
+dirtytime_expire_seconds
+
+When a lazytime inode is constantly having its pages dirtied, the inode with
+an updated timestamp will never get chance to be written out. And, if the
+only thing that has happened on the file system is a dirtytime inode caused
+by an atime update, a worker will be scheduled to make sure that inode
+eventually gets pushed out to disk. This tunable is used to define when dirty
+inode is old enough to be eligible for writeback by the kernel flusher threads.
+And, it is also used as the interval to wakeup dirtytime_writeback thread.
+
+==============================================================
+
dirty_writeback_centisecs
The kernel flusher threads will periodically wake up and write `old' data
--
1.8.3.1
^ permalink raw reply related [flat|nested] only message in thread
only message in thread, other threads:[~2018-06-18 23:59 UTC | newest]
Thread overview: (only message) (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2018-06-18 23:59 [PATCH v2] doc: add description to dirtytime_expire_seconds Yang Shi
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).