We will be introducing an op-code cache on our PHP based web nodes. Normally, PHP files have to be read and parsed for each request before they are executed. This processing time gets longer the more complex your site is. The cache temporarily stores the result of this step so it may be used for further requests eliminating processing overhead and the associated resource usage.

Our cache is based on XCache, however we will be using just the code-caching portion. If your application has native support for XCache, it will not be able to take advantage of it. Direct user access will not be supported.

We have tested and ensured compatibility with a very wide variety of common applications and code. Some applications may still exhibit behaviors like a blank white page or reporting errors. If the cache is suspected for the cause of the errors, it can be disabled in the .htaccess file with the following:

php_flag xcache.cacher 0

If the cache ends up not being the problem, please remove the entry to ensure you are getting the benefits of the cache.