mpstat is terrific for multi-processor servers. (You did get into this to play with big iron, didn’t you?) By itself the command:
mpstat
gives you average CPU statistics since the last boot.
The columns you’ll get are:
|
Time
|
CPU
|
%user
|
%nice
|
%system
|
%iowait | %irq | %soft | %idle | %intr/s |
| Time of reading |
which CPU |
time spent on user programs | time spent on any niced processes | time spent on system processes | time CPU sat idle waiting for disk I/O | time spent on normal interrupts | time spent on multi-processor interrupts | time CPU spent idle | interrupts per second |
You can ask for reports by CPU:
mpstat -P 0
This gives you information on processor 1 (i.e. this is a 0-based array).
Ideally, %user should be much higher than %system, which is simply overhead.
%idle really shouldn’t be greater than about 25%. (Why?)
intrs/s can be handy for detecting a device with communication problems. You need to know a baseline, so do record this number.
Ask for reports by interval and number of measurements:
mpstat 5 15
which decodes to “run mpstat every 5 seconds for 15 measurements.”