Polizeros is now running W3 Total Cache. You may notice the site is loading faster. (There were a few hiccups earlier in the day while installing it but those have been resolved.)
Caching software makes copies of frequently used pages, like the Home Page, then serves them up to those browsing the site. So, rather than WordPress having to load the php page, pull data from the database, then render the page, it simply uses the cached copy. This greatly cuts down on server usage and load, especially when you have hundreds of simultaneous users.
I switched caching software at the recommendation of Laughing Squid, our hosting company. Polizeros was bumping up against a compute cycles limit, which is the amount of processor time being used. They analyzed the site and said W3 is more powerful than the cache I was using and should help.
They may have a funny name, but Laughing Squid is the best host I’ve used. They host everything in the Rackspace Cloud. I can’t remember having downtime, and their tech support is superb. After some weird glitches trying to install W3 – which turned out to be a PHP memory limit issue – I emailed them and they did it for me.
Even better, if Polizeros does exceed the limits for the account, they simply upgrade the site in $4 a month increments so everything keeps going rather than blocking the site as some hosts do. That’s a big advantage of cloud computing. It scales as needed. Rackspace doesn’t do hosting for small sites per se, so that’s why I use Laughing Squid.
Big thanks to Jamie Holly at Intoxination for advice and help. If you ever get a 500 Server Error on your site or blog, check your .htaccess file, because that’s probably where the problem is. And make sure all remnants of the old cache are gone before installing the new one, otherwise a festive and alarming set of error messages may ensue.