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 get-
ting 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.
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 equa-
tion); 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 created.
OVERHEAD
Negligible.
SOURCE
This is from bpftrace.
https://github.com/iovisor/bpftrace
Also look in the bpftrace distribution for a companion _examples.txt
file containing example usage, output, and commentary for this tool.
This is a bpftrace version of the bcc tool of the same name. The bcc
tool may provide more options and customizations.
https://github.com/iovisor/bcc
OS
Linux
STABILITY
Unstable - in development.
AUTHOR
Brendan Gregg
SEE ALSO
dmesg(1)
USER COMMANDS 2018-09-07 oomkill.bt(8)
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