After running the database maintenance, details of which are below, on over 350 sites over the weekend, we noticed an increase in speed for our flagship site bryght.com (its database was reduced to 1/10 its original size!) as well as some of the sites we targeted for special attention. We're still waiting for word from those we've contacted specifically, so until we hear from them, we're not ready to say what we've done has successfully rooted out the 500 error problems people have been seeing on the hosted service. (We're waiting to hear from them as they are the people who watch over the site the most.) This evening we'll run the database maintenance on our newer sites, but we don't expect to see as much improvement as we did with the older sites, partly because the newer sites handle their individual databases better, and because at the outset we had the "Database Logging" module disabled by default. The equivalent module on older sites was filling up databases, making them run slowly for many operations.

A note on what we did to older databases, which we'll also do for newer sites tonight: we cleaned out the following database tables, which don't contain any content but rather user login sessions and old system logs: accesslog, watchdog, and sessions. Clearing out the last one means everybody on the site will be logged out. We hope that the inconvenience of having to login again is outweighed by a faster-running site overall. About 180 sites will undergo maintenance tonight, but like I say, we don't expect the performance gain to be the same as with older sites.

At any time during the day, please let us know if you encounter Internal Server 500 errors and what you were doing when it happened so we can take a deeper look. We will update this post with a comment when we're done with tonight's maintenance, and follow up with a post tomorrow morning.