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--- kernel_oom [2016/05/04 06:53] – luke7858
+++ kernel_oom [2024/05/23 07:26] (current) – external edit 127.0.0.1
@@ Line 1: / Line 1: @@
-=== OOM Killer ===
+=== Understanding OOM Killer ===
 OOM killer is invoked by the kernel when the system runs out of memory
 \\
 ^ File ^ Description ^
 | oom_adj | Since Linux Kernel 2.6.36 this file has been deprecated. The new file is oom_score_adj |
-| oom_score_adj | This file can be used to adjust the 'badness' which is used to select a process to kill in out-of-memory conditions \\ 0 (never kill) - 1000 (always kill)|
+| oom_score_adj | This file can be used to adjust the 'badness' which is used to select a process to kill in out-of-memory conditions \\ 0 (never kill) - 1000 (always kill) \\ If a task is using all its allowed memory, its badness score will be 1000, if its using hald of its allowed memory, its score will be 500 \\ The value of oom_score_adj is added to the badness score to determine which task to kill \\ Range -1000 to +1000 where '-' is always 0 (never killed) \\ |
-| oom_score | This displays the current score that the kernel has given to a process. The process score  |
+| oom_score | This displays the current score that the kernel has given to a process. The process score can increase or decrease depending on the following factors: \\ \\ - whether the process creates a lot of children using fork(2) (+); \\ - whether the process has a low nice value (i.e., > 0) (+); \\ - whether the process has been running a long time, or has used a lot of CPU time (-);\\ - whether the process is privileged (-); \\ - whether the process is making direct hardware access (-) |
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 Highest value in the file is killed first.