title: Trace Time Spent in wait4 Syscalls
name: wait4time.stp
version: 1.0
author: Daniel Berrange and Will Cohen
keywords: syscall wait4
subsystem: syscall
status: production
exit: user-controlled
output: trace
scope: system-wide
description: The script watches each wait4 syscall on the system. At the end of each wait4 syscall the script prints out a line with a timestamp in microseconds, the pid, the executable name in parentheses, the "wait4:" key, the duration of the wait and the PID that the wait4 was waiting for. If the waited for PID is not specified , it is "-1".
test_check: stap -p4 wait4time.stp
test_installcheck: stap wait4time.stp -c "sleep 0.2"