|oomkill.bt(8)||System Manager's Manual||oomkill.bt(8)|
oomkill.bt - Trace OOM killer. Uses bpftrace/eBPF.
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.
CONFIG_BPF and bpftrace.
- Trace OOM kill events:
- # oomkill.bt
- 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.
- 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 created.
This is from 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.
Unstable - in development.