Thanks to all of those who braved the cold snap and showed up for the Drupal Users Group monthly meeting for January 2009.
This was a case study on a site that was forced to move from a shared host to a VPS, yet was still slow, and how we diagnosed the problem, and found a solution for it.
Here are the slides for the talk, in PDF format.
One annoying aspect though is that almost all Drupal files use CVS style tags, such as the $Id$ one. Subversion does not recognize these by default.
We had a need from a client where they wanted to check certain complex conditions from a relatively big decision matrix. Without going into specifics, they wanted to check a progressive set of rules for users and taking certain actions when all the conditions were met.
Checking one or two conditions is not a problem on a modern day web site, but because the rules are progressive and have to be all checked from the start every time, that involves a lot of processing, a lot of database queries and basically a lot of time.
We have proposed a session for DrupalCon Washington DC 2009. The topic is one that is dear to our hearts and a common : Backend Drupal performance optimization and tuning: a guide for everyone.
This distills the many articles on Drupal performance tuning and optimizations on 2bits.com that we have written over the years.
Please vote for this session if you would like to attend.
As we observed before, configuring APC with low memory can be a drag on performance, causing high executing times.
We saw this recently for a client with a large web site on a dedicated server that approached 2bits.com for performance tuning.
A frequent problem we see at client sites is when they click submit on a page, whether it is a creation of a node or a comment, and then the site does not come back for several minutes.
Is your Drupal or WordPress site slow?