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Date: Tue, 1 Aug 2006 16:13:08 +0200
From: Jan-Frode Myklebust <mykleb@no.ibm.com>
To: Andrew Morton <akpm@osdl.org>
Cc: linux-kernel@vger.kernel.org
Subject: [PATCH] oom_adj/oom_score documentation
Message-ID: <20060801141307.GA18159@99RXZYP.ibm.com>
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I was looking for the a way around an OOM-problem, and found
a couple of undocumented new features for tuning the OOM-score
of individual processes. Here's a small documentation patch for
/proc/<pid>/oom_adj and /proc/<pid>/oom_score.

Signed-off-by: Jan-Frode Myklebust <mykleb@no.ibm.com>

---

diff --git a/Documentation/filesystems/proc.txt b/Documentation/filesystems/proc.txt
index 99902ae..81bb8ea 100644
--- a/Documentation/filesystems/proc.txt
+++ b/Documentation/filesystems/proc.txt
@@ -39,6 +39,8 @@ Table of Contents
   2.9	Appletalk
   2.10	IPX
   2.11	/proc/sys/fs/mqueue - POSIX message queues filesystem
+  2.12	/proc/<pid>/oom_adj - Adjust the oom-killer score
+  2.13	/proc/<pid>/oom_score - Display current oom-killer score
 
 ------------------------------------------------------------------------------
 Preface
@@ -1958,6 +1960,21 @@ a queue must be less or equal then msg_m
 maximum  message size value (it is every  message queue's attribute set during
 its creation).
 
+2.12 /proc/<pid>/oom_adj - Adjust the oom-killer score
+------------------------------------------------------
+
+This file can be used to adjust the score used to select which processes shall
+be killed in an out-of-memory situation.  Giving it a high score, increase the
+likelihood of this process being killed by the oom-killer. Valid values are in
+the range [-16:15], plus the special value '-17', which defeat the  oom-killer
+altogether.
+
+2.13 /proc/<pid>/oom_score - Display current oom-killer score
+-------------------------------------------------------------
+
+This file can be used to check what the  current score  used by the oom-killer
+is for any given <pid>. Use it together with /proc/<pid>/oom_adj to tune which
+process will be killed in an out-of-memory situation.
 
 ------------------------------------------------------------------------------
 Summary
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