PHP sites stop loading - Apache continues to work

[todgerme]

Hi,

To anyone that can help - thank you in advance.

I have a small issue on one of my shared servers whereas it randomly without warning Apache processes begin to hang.

It began to happen a few weeks ago and I would assume it's a piece of code that a user has uploaded but I just can't figure out how to go about debugging the problem and finding the code. Nothing in Apache logs and nothing in the Syslog either.

Apache continues to serve html/cgi/perl and jsp pages without issue throughout the problem and if you do a /server-status - you see all PHP requests with a "W" which is meant to be sending reply - but none of the sites are working - even a basic <?php header(redirect to some url); ?> isn't working. PHP is loaded via dso module only and there have been no updates installed for quite a while. APC and Suhosin are installed too and have given no issues for a long time.

A restart of Apache instantly fixes the issue for X weeks again ...

Anyone lend some advice as to how to fix the issue/identify the issue with PHP?

Thanks,

Keith