Page requests are extremely slow

[youngmoney]

Like the title said, loading pages is slow. Too slow.

`top` reports my server isn't going below 1.7GB of free RAM and, when requesting pages, the CPU usage peaks at 20%. So hardware isn't the issue.

I piped /dev/urandom to a file and got about 20MB worth of crap that I then downloaded to my computer. It's coming down at about 900Kbps. Bandwidth isn't the issue.

I've tried loading Joomla, Magento and KnowledgeTree (a Document Management System) on my VPS. All three are slow. So the problem doesn't lie in badly written code.

I enabled MySQL Query Caching to try speed things up and that helped a little bit but no where near enough. What's causing the speed issue?

I tried switching from suPHP to DSO (the PHP handler) but that didn't help. What can I do to speed up apache/php on WHM/Cpanel?

 

[Spiral]

I've tried loading Joomla, Magento and KnowledgeTree (a Document Management System) on my VPS.

There is part of your problem there!

VPS servers have never been well known for performance and in fact that and security issues are both consistently major problem points.

(Note when I say "VPS" here I am referring to traditional VPS servers and not the newer technologies like "Cloud" that also sometimes get referred to as VPS as well)

I enabled MySQL Query Caching to try speed things up and that helped a little bit but no where near enough. What's causing the speed issue?

This is a step in the right direction but there is a lot more to optimizing MySQL than just simply the query cache and there is a whole lot more areas of your server that you will want to tune and optimize that have absolutely nothing to do with MySQL.

Apache is going to be one of the larger areas to look at particularly your traffic and timeout settings, what modules are loaded, and if you are using an MPM or not in your configuration. You can also look at page compression (biggest help) and caching options.

Optimization and tuning though is really a whole field in and of itself.

I tried switching from suPHP to DSO (the PHP handler) but that didn't help. What can I do to speed up apache/php on WHM/Cpanel?

I only make this comment to stress the point hard -- That was idiotic!

While suPHP itself is, if you want to get technical, a bit slower than DSO per final page display primary because of underlying technical differences in the way that it operates that I am not going to bother to try to explain here, it would actually end up using less resources and allow faster processing of your PHP code both of which are better for your server from a performance aspect.

Aside from likely having all the wrong permissions though, you open yourself up to major security threats and other problematic complications changing over to DSO and ironically make yourself more likely to run into performance bottlenecks ---- bad, bad, bad idea!

SuPHP actually is the better choice EVEN FOR PERFORMANCE REASONS if you were going to have to choose one of those for your server!

However, with that said, my personal recommendation to you would be FCGI as it sounds like you may have enough memory for it and it outperforms both DSO and SuPHP significantly when setup properly.

If I saw your server, I could probably tell you fairly quick what is causing your bottlenecks and what would need to change aside from the server itself but hopefully these comments helps point you in the right direction.