Re: Is monit deterministic?

Lutz Mader <[email protected]> Fri, 23 Dec 2022 00:33:41 +0100
Newsgroups gmane.comp.monitoring.monit.general
Message-ID <[email protected]>
Hello Leonard Teng,
from my point of view monit is not the problem sometimes.

> I just wanted to inquire on whether monit is guaranteed to perform service
> restarts in high CPU/RAM usage situations? 

From the monit point of view, monit can handle low free RAM or RAM
shortage, but restarts can not handle sometimes. I find "out of memory"
conditions on Linux and AIX systems with a RAM shortage all the time
monit try to start a command to try a restart or anything else.

> Wanted to know if I need to be
> conservative in setting thresholds for CPU/RAM usage for services.

You should use conservative thresholds.

But it depence to your systems,
Lutz

Appendage:
On AIX systems I use cpu and memory threadholds up to 95%.

check system $HOST
  every 5 cycles
  if cpu usage > 95% for 10 cycles then alert
  if memory usage > 95% for 20 cycles then alert
  if swap usage > 50% for 20 cycles then alert
  if swap usage > 30% for 5 cycles then exec
"/usr/local/etc/monit/scripts/aixpgsp.sh 500"
     repeat every 20 cycles