cloudry wrote:
My apache is timing out again...This is killing me

my visitors at my startup are getting stuck

!!
Well, are we talking about a different problem? What do you mean by "timing out"?
Your Lish/console output showed that you were OOMing previously. Dropping the MaxClients should have helped prevent that but depending on your load (and time to process each request) could certainly create very lengthy delays in processing since now you've bottlenecked things to only 2 concurrent requests. I'm not sure if that matches what you are describing as Apache timing out, but with long enough delays I assume clients might give up.
Assuming, as you indicate, that you still have free memory with this configuration, start increasing MaxClients as long as you still have free memory and you should increase performance (as long as you don't CPU bottleneck or I/O bottleneck with, for example, database I/O). Just don't go so far that you start swapping since that's I/O you can avoid.
If you get as high as you can (memory-wise) and still can't keep up with your request load, then you've got to look at ways at improving the time to process single requests. Your use of APC is definitely already a good thing, but you might find, for example, that fronting Apache with a lower resource server (like nginx) for static content can help, since it lets the higher load Apache PHP processes only get used when necessary. Looking through some of the apache tuning forum threads (I'm pretty sure some specifically discussed wordpress) may be of help at that point.
Of course, worst case is to just grow your Linode to get more memory (and thus the ability to have additional concurrent processes) but until it's clear that you can't tune things within your current memory I wouldn't jump to that point since otherwise it might not actually help anyway.
-- David