Some wise soul decided many moons ago that installing the aforementioned plugin on a site I host is a great ideea. The wise soul is long gone (admining websites for ngo’s as a volunteer is no fun for far too many come and goers:) ) Lately the site was getting more and more sluggish with no apparent reason. I decided to clean a bit the many modules he thought in his wisdom to install. Like any major work on a site I started with a backup. I was puzzled to see that mysqldump would hang. I checked, it was not hanging, it was dumping a really huge .sql file. That was not normal as the site only has a few hundreds of articles. A check in phpmyadmin later and I found the culprit:
WPPREFIX_cbnetpo_ping_optimizer table had over 11Gb. Great, 82 million records for some errors about not being able to ping. Great: no limit on how much you log in the table, no throttling on errors (each error is logged tens of times in the same second) and so on. I could track where this comes from but I simply removed the darn plugin and dropped the table.
So great idea on installing untested plugins and great coding by the plugin author.