Forum OpenACS Q&A: Re: Re: Kernel Parameter: PerformanceModeP and PermissionCache

In some respects, you are asking the wrong question. The first question to ask is, what is the resource that is being used most heavily? Is it disk I/O, CPU usage, network bandwidth, or RAM/virtual memory? My guess is disk I/O or RAM.

Once you know what the bottleneck is, then you can figure out how to solve it.

Use iostat, sar, and vmstat to figure out what is going on. I have found sar to be useful, but you have to turn it on first and it is more of a "what happened" rather than "what is currently happening" tool.