check_cpu.md
IML Checks for Icinga / Nagios
check CPU
Introduction
check_cpu is a plugin to check cpu usage and cpu io wait. It reads cpu data from output of top command and shows
hwi - Time spent handling hardware interrupt routines. (Whenever a peripheral unit want attention form the CPU, it literally pulls a line, to signal the CPU to service it) swi - Time spent handling software interrupt routines. (a piece of code, calls an interrupt routine...) st - Time spent on involuntary waits by virtual cpu while hypervisor is servicing another processor (stolen from a virtual machine)
nice - Time spent running niced user processes (User defined priority) wait - Time spent on waiting on IO peripherals (eg. disk)
system - Time spent in kernel space user - Time spent in user space idle - Time spent in idle operations
For all values it sends performance data.
If there are processes with status D they will be shown (to analyze cpu waits).
Syntax
$ check_NAME [-c CRITICAL] [-w WARING] [-i CRITICAL_IO]
Parameters
-w VALUE cpu usage warning level (default: 75)
-c VALUE cpu usage critical level (default: 90)
-i VALUE io wait critical level (default: 50)
-h or --help show this help.
Examples
check_cpu -w 60 -c 80 -i 40
check cpu usage.
It shows a warning if usage is higer 60%.
It shows critical status if usage is higer 80% or io wait is 40%