I wanted to try Piwik so I purchased a small KVM VPS with 512MB memory 512MB swap, and installed Centos 6.6 64bit and set up Piwik. Everything works, and I set up just 4 sites that get around 30 visits a day max. After a day or two I started looking at the statistics and found the interface to be glacially slow. I put htop on the VPS and can see that when it is simply monitoring hits, the load is around 0.2, but the moment I start trying to use the GUI to look at the stats the load goes up to 6 and above.
Does this sound reasonable? In other words, am I overloading my VPS, I should have purchased a bigger VPS, more memory, or have I done something wrong in setup, 4 small sites and using the GUI should not overload a VPS with these resources. Or anything else?