I did some emergency unannounced database maintenance just now to have another go at fixing some random table corruption that's been causing MySQL to crash randomly.

It's strange because the actual table files aren't getting corrupted (they're read-only tables and md5's of the files aren't changing!) so barring hardware problems, which I've mostly ruled out, it's gotta be the main innodb files getting hosed -- so I converted all tables to MyISAM, blew out the innodb files, and converted them back. To do that means running without transactions, which means weird things can happen (like comments getting the wrong person's name stuck on them) so I shut the site down as a precaution.

If this doesn't fix it then I may have to have another look at hardware, however, I've checked it out pretty thoroughly (no ECC problems with the memory, CPU temperature's fine, power supply seems OK, no apparent problems with the RAID controller or disks...) and after that it's looking for bugs in the OS I guess.

New comment counters being wrong are an unrelated problem; I'm working on that as a separate issue. But the red line should always appear in the correct place and clicking the (sometimes wrong) number will always jump to the correct new comment anyway.