Nagios, 2nd Edition

Appendix F. Tips on Optimizing Performance

It is very difficult to describe, in general terms, a Nagios installation that performs well. Nagios should perform checks immediately, that is, it should have a small latency time for host and service checks. This is the difference between the planned and actual execution times of the check. If this is an hour or more, you can certainly talk about disastrous performance. On the other hand, latency of less than a second represents very good performance. In between these extremes, the borders between acceptable and unacceptable are somewhat hazy.

The latency time of host and service checks can be measured objectively. Other, more subjective impressions are more difficult to evaluate. Doggedly working on ...