>>>>> I ran into an out of memory problem. The first mention of it in the >>>>> kernel log is "mysqld invoked oom-killer". I haven't run into this >>>>> before. I do have a swap partition but I don't activate it based on >>>>> something I read previously that I later found out was wrong so I >>>>> suppose I should activate it. Is fstab the way to do that? I have a >>>>> commented line in there for swap. ... > Also, run a caching proxy if at all possible. That made the single > biggest difference for my server. > > Other useful things: > * Set the MaxRequestsPerChild to something like 450. As part of their > caching, things like mod_php will grow the process size a bit as the > apache process gets old in the tooth. Setting MaxRequestsPerChild > lower causes the process to expire and be replaced sooner. On my > server, I see apache processes consume about 60MB towards the end, and > then cycle back and consume about 22MB.
Default is 10000 so 450 might be too low. > * On my server, I have MinSpareServers at 10, and MaxSpareServers at > 12. I handle spikes pretty well, and free the memory quickly. I use 20 and 40 for Min and Max respectively. > * If you're using PHP, set memory_limit in php.ini as low as your > applications can survive. > > I'm assuming you're running on a VPS or similar. At 512MB of RAM with > a web server and database server, you need to keep things very tight. I have 4GB RAM. 512MB is the size of my currently unused swap partition. - Grant
