Recent reports of large increases in the amount of comment spam and the server load required to handle it have forced many web hosting companies to shut down installations of Movable Type and caused MT developer Six Apart to quickly begin working on a patch for the problem.
“Recently there have been a number of reports about the escalating effect of comment spam on Movable Type installations,” said Jay Allen, Movable Type product manager and creator of anti-comment spam tool MT-Blacklist.
A problem that has plagued the blogging software since fall of 2003, comment spam, also referred to as “link spam,” is supposed to boost a website’s rating in search engines like Google by continuously bombarding the comment sections on blogs with links.
“At first, we assumed that these problems were caused mainly on legacy systems running without the benefit of the modern anti-spam measures,” Allen said. “After further analysis and load testing, we’ve actually found that this is not the case.”
According to Allen, the problem was is caused by a glitch in the MT software that causes page rebuilding even in the case of a comment submission that would normally be moderated. Essentially, this generates a new page every time a comment is submitted, even if the comment won’t appear on the page until it is approved.
“In addition, we have found another less severe instance of unnecessary database connections which would normally be associated with dynamic pages, even if dynamic templates are not in use,” Allen said. “This would adversely affect any customer not using static pages by adding the overhead of dynamic files on top of the normal load caused by rebuilding of static sites.”
Both patches are in development and expected to be released within 48 hours.