I have a server that contains five separate WordPress installations. I’ve maintained these WordPress installations on the same NGINX (with php5-fpm) server and lately have been realising that the websites have been having some issues with the MySQL database crashing.
Upon investigating the server’s details through New Relic I found that the server was running low on physical memory.
At present the server has 512MB of RAM and the two largest processes on this server are PHP5-FPM and MySQL – both of these combining to about 60-70% of the RAM available! With all process totalling around 85% of all RAM available.
Knowing this was likely to cause issues down in the future (especially if another WordPress install occurs!) I began investigating ways of mitigating the processes chewing all the available RAM and one such method was by installing the awesome WordPress plugin WP Super Cache.
Upon installing this process I immediately noticed a drop in the total amount of RAM consumption from the server’s running processes. No longer was I running at 85% capacity, now I was politely humming at 55%!
I also noticed a dramatic decrease in page speed for one of the WordPress sites, where BEFORE installing the cache plugin the home page of the site was running at an average of about 3.1 seconds and AFTER the plugin installed the home page was running at an average of 1.9 seconds!
So not only have I received less RAM consumption I’ve also received better page loads.