отображать и настраивать оценку OOM-killer (display and adjust OOM-killer score.)
Имя (Name)
choom - display and adjust OOM-killer score.
choom -p
PID
choom -p
PID -n
number
choom -n
number [--] command [argument ...]
Описание (Description)
The choom
command displays and adjusts Out-Of-Memory killer score
setting.
Параметры (Options)
-p
, --pid
pid
Specifies process ID.
-n
, --adjust
value
Specify the adjust score value.
-h
, --help
Display help text and exit.
-V
, --version
Display version information and exit.
Примечание (Note)
Linux kernel uses the badness heuristic to select which process
gets killed in out of memory conditions.
The badness heuristic assigns a value to each candidate task
ranging from 0 (never kill) to 1000 (always kill) to determine
which process is targeted. The units are roughly a proportion
along that range of allowed memory the process may allocate from
based on an estimation of its current memory and swap use. For
example, if a task is using all allowed memory, its badness score
will be 1000. If it is using half of its allowed memory, its
score will be 500.
There is an additional factor included in the badness score: the
current memory and swap usage is discounted by 3% for root
processes.
The amount of "allowed" memory depends on the context in which
the oom killer was called. If it is due to the memory assigned to
the allocating task's cpuset being exhausted, the allowed memory
represents the set of mems assigned to that cpuset. If it is due
to a mempolicy's node(s) being exhausted, the allowed memory
represents the set of mempolicy nodes. If it is due to a memory
limit (or swap limit) being reached, the allowed memory is that
configured limit. Finally, if it is due to the entire system
being out of memory, the allowed memory represents all
allocatable resources.
The adjust score value is added to the badness score before it is
used to determine which task to kill. Acceptable values range
from -1000 to +1000. This allows userspace to polarize the
preference for oom killing either by always preferring a certain
task or completely disabling it. The lowest possible value,
-1000, is equivalent to disabling oom killing entirely for that
task since it will always report a badness score of 0.
Setting an adjust score value of +500, for example, is roughly
equivalent to allowing the remainder of tasks sharing the same
system, cpuset, mempolicy, or memory controller resources to use
at least 50% more memory. A value of -500, on the other hand,
would be roughly equivalent to discounting 50% of the task's
allowed memory from being considered as scoring against the task.