Manual: oomkill.bt

oomkill.bt(8)					   System Manager's Manual				       oomkill.bt(8)

NAME
       oomkill.bt - Trace OOM killer. Uses bpftrace/eBPF.

SYNOPSIS
       oomkill.bt

DESCRIPTION
       This traces the kernel out-of-memory killer, and prints basic details, including the system load averages at the time
       of  the	OOM  kill.  This  can provide more context on the system state at the time: was it getting busier or steady,
       based on the load averages? This tool may also be useful to customize for  investigations;  for	example,  by  adding
       other task_struct details at the time of OOM, or by adding other commands to run at the shell.

       Since this uses BPF, only the root user can use this tool.

REQUIREMENTS
       CONFIG_BPF and bpftrace.

EXAMPLES
       Trace OOM kill events:
	      # oomkill.bt

FIELDS
       Triggered by ...
	      The process ID and process name of the task that was running when another task was OOM killed.

       CGROUP ...
	      If the OOM occurs in the memory cgroup, display the memory cgroup information.

       OOM kill of ...
	      The process ID and name of the target process that was OOM killed.

       loadavg
	      Contents of /proc/loadavg. The first three numbers are 1, 5, and 15 minute load averages (where the average is
	      an exponentially damped moving sum, and those numbers are constants in the equation); then there is the number
	      of  running tasks, a slash, and the total number of tasks; and then the last number is the last PID to be cre‐
	      ated.

OVERHEAD
       Negligible.

SOURCE
       This is from bpftrace.

	      https://github.com/bpftrace/bpftrace

       Also look in the bpftrace distribution for a companion _examples.txt file containing example usage, output, and	com‐
       mentary for this tool.

       This  is	 a  bpftrace  version of the bcc tool of the same name. The bcc tool may provide more options and customiza‐
       tions.

	      https://github.com/iovisor/bcc

OS
       Linux

STABILITY
       Unstable - in development.

AUTHOR
       Brendan Gregg, Rong Tao

SEE ALSO
       dmesg(1)

USER COMMANDS						 2018-09-07					       oomkill.bt(8)