Thank you for replying, and sorry for not checking back here sooner.
>_Crashing_? Under heavy load a server
will get slower, it may get blocked _temporarily_, but should not crash!
>What is the load? What parameters do you monitor? What is the indicator of a crash?
There are a few ways in which it will go.
1 - Apache will restart the service within itself giving a "Parent: child process exited with status 1 -- Restarting" error after a "FATAL: emalloc(): Unable to allocate xxxxxx bytes" or "FATAL: erralloc(): Unable to allocate xxxxxx bytes"error. These are most common, and clear pretty quickly, but may interupt work.
2 - We get JustInTime Debugger errors on the server that must be cleared for the site to respond. Generally the site will be ok for a few seconds, then we'll then get a stream of "(OS 64)The specified network name is no longer available. : winnt_accept: Asynchronous AcceptEx failed." errors, then a restart like above and all is well in a few more seconds.
3 - Sometimes it will stop responding but there are not JIT errors to clear, so we have to restart the services.
> Quad 1.6 GHz, 8 GB RAM is lot of beef.
Should be fine, right?
You've seen this one http://docs.moodle.org/en/Performance
Yeah, but I'm hoping for something a bit more in depth, as the basics haven't really taken us far enough, and the advanced stuff is still beyond me.
> Then take an OS which allows that ;-(
Ha ha I have suggested it, but we are a Microsoft institution.
One thing I have noticed is that it seems like some of the errors occur just as I log into the site, as me but with administrator role. It sounds odd, but it's seeming more and more like a solid lead.