Intensive PHP script failing w/ “The timeout specified has expired” error / ap_content_length_filter

Question

Running a MySQL intensive PHP script that is failing. Apache log reports this:

[Wed Jan 13 00:20:10 2010] [error] [client xxx.xx.xxx.xxxx] (70007)
The timeou         


        

Answer 1

for anyone that may come across this. I was able to solve this by looking into memcache.

my situation:

1. a memcached server that is being used by multiple apache servers
2. memcached.sess_locking = On
3. make back to back requests on the same session (within ms of each other)

outcome: the second requests gets stucks and times out

solution 1: set memcached.sess_locking = Off in your php.ini

Solution 2: decrease memcached.sess_lock_wait_min

why it works: when a second request comes in while first one has locked the session file, the second session has to wait. If memcached.sess_lock_wait_min is set too high it just waits that long before trying to get the possession of the lock. it is super easy to test this using sess_locking = Off. If it does help you then you definitely want to play around with lock time values to see what works better for you.