I've been wondering about WordPress plugin overhead for some time. How does one keep track of how much processor time and overhead any given plugin requires?
We run fairly streamlined WordPress installs at Foliovision with about 30 active plugins per site. A lot of them are one-trick ponies developed in-house so we know the code isn't creating a huge load.
But anyone who has been working on Macintosh computers from the old days (System 7, 8 & 9) knows very well that every extensions (and some people were running 50 of them) slows down your compuer and increases the chances of a system conflict. There were whole expensive utilities devoted to keeping extensions and control panels under control. Any one else remember long hours spent with Conflict Catcher?
Here's what WPdesigner.com has to say on his own plugin issues:
With the WP Download Monitor plugin, the front page of my blog had to operate with 136 queries on every page load. After uninstalling that plugin, the front page needed only 10 queries to work. 136 versus 10 and all I have to do is give up tracking the downloads, hmmm.. oh what, oh what should I do? I deactivated / uninstalled it, of course.