lkml.org 
[lkml]   [2014]   [Dec]   [17]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
Date
From
SubjectRe: [PATCH 2/2] task_mmu: Add user-space support for resetting mm->hiwater_rss (peak RSS)
On Mon, 15 Dec 2014 17:15:33 +0000 Petr Cermak <petrcermak@chromium.org> wrote:

> Peak resident size of a process can be reset by writing "5" to
> /proc/pid/clear_refs. The driving use-case for this would be getting the
> peak RSS value, which can be retrieved from the VmHWM field in
> /proc/pid/status, per benchmark iteration or test scenario.

The term "reset" is ambiguous - it often means "reset it to zero".

This?

--- a/Documentation/filesystems/proc.txt~task_mmu-add-user-space-support-for-resetting-mm-hiwater_rss-peak-rss-fix
+++ a/Documentation/filesystems/proc.txt
@@ -488,7 +488,8 @@ To clear the bits for the file mapped pa
To clear the soft-dirty bit
> echo 4 > /proc/PID/clear_refs

-To reset the peak resident set size ("high water mark")
+To reset the peak resident set size ("high water mark") to the process's
+current value:
> echo 5 > /proc/PID/clear_refs

Any other value written to /proc/PID/clear_refs will have no effect.
--- a/fs/proc/task_mmu.c~task_mmu-add-user-space-support-for-resetting-mm-hiwater_rss-peak-rss-fix
+++ a/fs/proc/task_mmu.c
@@ -859,7 +859,7 @@ static ssize_t clear_refs_write(struct f
if (type == CLEAR_REFS_MM_HIWATER_RSS) {
/*
* Writing 5 to /proc/pid/clear_refs resets the peak resident
- * set size.
+ * set size to this mm's current rss value.
*/
down_write(&mm->mmap_sem);
reset_mm_hiwater_rss(mm);
_


\
 
 \ /
  Last update: 2014-12-18 00:01    [W:0.067 / U:1.544 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site