| 1234567891011121314151617181920212223 |
- What: /proc/<pid>/oom_adj
- When: August 2012
- Why: /proc/<pid>/oom_adj allows userspace to influence the oom killer's
- badness heuristic used to determine which task to kill when the kernel
- is out of memory.
- The badness heuristic has since been rewritten since the introduction of
- this tunable such that its meaning is deprecated. The value was
- implemented as a bitshift on a score generated by the badness()
- function that did not have any precise units of measure. With the
- rewrite, the score is given as a proportion of available memory to the
- task allocating pages, so using a bitshift which grows the score
- exponentially is, thus, impossible to tune with fine granularity.
- A much more powerful interface, /proc/<pid>/oom_score_adj, was
- introduced with the oom killer rewrite that allows users to increase or
- decrease the badness score linearly. This interface will replace
- /proc/<pid>/oom_adj.
- A warning will be emitted to the kernel log if an application uses this
- deprecated interface. After it is printed once, future warnings will be
- suppressed until the kernel is rebooted.
|
