I am facing some issues with memcached under heavy load.
I am using ab to stress test my site. I use one instance of memcached to store php sessions and another one to store objects.
While benchmarking the site, I often get exceptions from the site which have to do with failing get() from memcache.
The key definitely exists in memcached.
I have configured max connections to 4096 and I run ab as
ab -c 200 -t 60
I am using php-memcache-2.2.6 client library.
Also I am monitoring memcached during the test and the
curr_connections variable never goes higher than 250
Additionally, listen_disabled_num is 0
What could be causing such failures?
Thanks