Originally Posted by NSWKim
You might try running a "pstree" or "ps faux" to get an idea of all the threads and what sort of memory they are using. Chances are there's a memory leak in one of the applications. I've also seen problems with bad RAM which make swap fill up to 100% then the machine crashes. You can check you free memory and swap with a "free -m".
Mmmm, it seems that during normal operation there are 20 instances of httpd, each consuming 2% of memory (that adds up to 40%). But apart from that, and 3% for mysqld, there are no other processes consuming memory.
The thing is also, if there is a memory leak, it is not continuous, and only shows from time to time (once every other day, more or less). Is that possible?