Within an site I am presently writing, I am facing an unusual, mind-dazzling behavior: after seconds of 100% CPU usage, the server is reacting nothing, only closing the bond. Basically limit lower the job of the request, it begins being employed as normal.

XDebug is showing the bottleneck is not SQL, but instead CPU usage (some function calls 20000 occasions, many object instances etc.). Another interesting side-effect: the request time is substantially longer Firebug is giving me 600ms for any working request, and a pair of,2s for any emptily terminating request with only be used as much work.

I am confident it's not the execution time period limit (it's set to indefinite), nor the memory limit (as no PHP Error returns).

For that record, I am using: Apache 2.2.12 mpm-prefork/Ubuntu, PHP 5.2.10
Similar behavior continues to be observed on Home windows.

Any hints to describe this behavior? Is maybe Apache killing threads he supposes to stay in an imprecise loop? Or perhaps is there some log file I possibly could take a look at?

Apache's error.log says

zend_mm_heap corrupted

that is resulting in a PHP Bug page by having an workaround. It appears to look under heavy load and might be associated with a zend_extension.