Slow queries are a major pain in the ass and should be avoided by all means necessary if the site in question is under heavy load. It's bad for performance. Very bad.
Wednesday, November 26, 2014 - 15:58
Thursday, February 7, 2013 - 06:21
One of the servers we care for recently got hit by an unexpected amount of traffic. That was not related to mentioned rogue crawlers. It basically required more power to deal with it. After the refit the server appeared to be back to normal operations. There was no need at that point for special fine tuning...or so I believed.