blob: 0677e49ef34ee4a9a7cd4de27f7673ccfcad14d1 [file] [log] [blame]
#!/usr/bin/env python
# oomkill Trace oom_kill_process(). For Linux, uses BCC, eBPF.
# This traces the kernel out-of-memory killer, and prints basic details,
# including the system load averages. This can provide more context on the
# system state at the time of OOM: 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.
# Copyright 2016 Netflix, Inc.
# Licensed under the Apache License, Version 2.0 (the "License")
# 09-Feb-2016 Brendan Gregg Created this.
from bcc import BPF
from time import strftime
import ctypes as ct
# linux stats
loadavg = "/proc/loadavg"
# define BPF program
bpf_text = """
#include <uapi/linux/ptrace.h>
#include <linux/oom.h>
struct data_t {
u64 fpid;
u64 tpid;
u64 pages;
char fcomm[TASK_COMM_LEN];
char tcomm[TASK_COMM_LEN];
void kprobe__oom_kill_process(struct pt_regs *ctx, struct oom_control *oc, const char *message)
unsigned long totalpages;
struct task_struct *p = oc->chosen;
struct data_t data = {};
u32 pid = bpf_get_current_pid_tgid();
data.fpid = pid;
data.tpid = p->pid;
data.pages = oc->totalpages;
bpf_get_current_comm(&data.fcomm, sizeof(data.fcomm));
bpf_probe_read(&data.tcomm, sizeof(data.tcomm), p->comm);
events.perf_submit(ctx, &data, sizeof(data));
# kernel->user event data: struct data_t
TASK_COMM_LEN = 16 # linux/sched.h
class Data(ct.Structure):
_fields_ = [
("fpid", ct.c_ulonglong),
("tpid", ct.c_ulonglong),
("pages", ct.c_ulonglong),
("fcomm", ct.c_char * TASK_COMM_LEN),
("tcomm", ct.c_char * TASK_COMM_LEN)
# process event
def print_event(cpu, data, size):
event = ct.cast(data, ct.POINTER(Data)).contents
with open(loadavg) as stats:
avgline =
print(("%s Triggered by PID %d (\"%s\"), OOM kill of PID %d (\"%s\")"
", %d pages, loadavg: %s") % (strftime("%H:%M:%S"), event.fpid,
event.fcomm.decode('utf-8', 'replace'), event.tpid,
event.tcomm.decode('utf-8', 'replace'), event.pages, avgline))
# initialize BPF
b = BPF(text=bpf_text)
print("Tracing OOM kills... Ctrl-C to stop.")
while 1: