My Apache processes occasionally get stuck on one request and stop doing
anything useful. There's no progress on that request (as judged by
tracing ethernet traffic or system calls), yet Apache's TimeOut
directive does not kick in.
This problem is apparently related to PHP, as it occurs only for
requests served using mod_php. When serving plain files, the connection
is properly aborted at the times prescribed by Apache's TimeOut directive.
I've tested this with two configurations:
1. Debian's apache 1.3.26-0woody3 (including Debian's patches)
+ stock PHP 4.3.0
2. Stock Apache 2.0.47 with preform MPM,
+ stock PHP 4.3.2, configured ...