Moodle server crashing due to apache using too much memory?

[reggiep]

HAs anyone else had this issue?

I am running moodle 2.5 on a virtual server with 8Gbytes of memory on ubuntu, having moved from running it on an old pc!

 

Anyway now when more than about 16 students log in moodle starts to struggle and then gives up, and I get errors "Out of memory: Kill process 5458 (apache2)"

running top before the crash shows an awful lot of apache processes.

 

Is there a way to manage how apache manages its memory usage and amount of processes?

 

Thanks

[pcstru]

Generally [*1] you need to look at the parameters associated with the prefork module :

 

StartServers, MinSpareServers, MaxSpareServers, ServerLimit, MaxClients, MaxRequestsPerChild.

 

I found some good info on optimising Apache for wordpress (this one is particularly relevant), much of that will apply to Moodle. Generally, figure out your overheads (MySQL, the core Apache service and any other memory resident processes), figure out the size of the process Apache uses to service a Moodle connection, then given your RAM, set the parameters such that you don't run out of RAM and start paging.

 

[*1] This may not be true if apache2 is configured into worker mode, but that should be unlikely.

Edited February 27, 2014 by pcstru

[pete]

Apache (even in as-shipped default config) shouldn't be running out of ram with 16 students and 8GB of RAM.

 

show us the output of the "top" command (or better yet, "htop" - you'll need to install it) so we can see what's consuming the RAM.

 

....unless you've got a bizarre apache config.