Thanks so much for your response. I’ve tried switching to the default theme and no luck. The query is actually really slow from the mysql command line. We have 200000+ posts and 50 categories. This is the query that gets run from the top level category (which is parent to all 50 categories). The site only displays 20 entries but MySQL is creating a temporary table to scan the results because of the group by clause. The order by seems to cause MySQL to use a filesort as well. There are indexes on the tables, but it doesn’t look like they’re being used efficiently. I’m not sure where to go with this other than to try to rewrite the query more efficiently.