Quoting Big Brother ignorance.is.strength@gmail.com:
Thanks for the responses.
I have too many modules to list them all... it would take too long.
It's something to do with MySql accessing the comments table. It then locks and hangs.
I am not using persistent connections.
The Processlist indicates a number of 'SELECT count(node.nid) FROM node LEFT JOIN comments' statements which send data forever, and a few 'SELECT node.nid, comments.timestamp' which copy to tmp forever.
Possible relevant modules: Karma Path Localizer Panels
The only suggestion I have is for you to start turning off modules until you find the one causing the problem and then open an issue for that module. It may be a combination of modules causing an issue; some modules are not compatible with other modules. If you find a combination issue then open an issue in both modules so that they can document the travesty.
Earnie -- http://for-my-kids.com/ -- http://give-me-an-offer.com/