Synopsis: Some URLs make the httpd process eat all CPU State-Changed-From-To: open-analyzed State-Changed-By: marc State-Changed-When: Sun Jul 20 22:51:00 PDT 1997 State-Changed-Why: What you say doesn't entirely make sense; one process eating 100% CPU should not stop other processes from serving requests due to the fact that Unix is an operating system, unlike Windows.
Can you reproduce the problem 100% of the time? Try cutting your config files to the minimum possible. If you have mod_rewrite compiled into your server, try temporarily removing it and recompiling. Try compiling with a minimum of modules. Try running a ktrace on the runaway process (eg. ktrace -p 666, then ktrace -C to stop it, then kdump to dump the output) to see what it is doing.
