While investigating a slow WordPress installation, I came across this post on how to check if autoloaded options are a factor in the slowdown.
I had no idea that plugins would leave so much junk behind! Here are the two queries to investigate. One to see how big the total options are, and the second to find the worst offenders.
SELECT SUM(LENGTH(option_value)) as autoload_size FROM wp_options WHERE autoload=’yes’;
SELECT LENGTH(option_value),option_name FROM wp_options WHERE autoload=’yes’ ORDER BY length(option_value) DESC LIMIT 15;
For the site I was working on, I set the unnecessary options to autoload=’no’ … just in case it would affect the site.