MT-Blacklist: Technical Difficulties

by Joe Katzman at October 15, 2003 6:03 AM

Since installing MT-Blacklist plugin to stop comment spam, Winds of Change.NET has begun experiencing technical difficulties. Rebuilds have been hanging, server CPU usage has spiked into the stratosphere, and the server was even brought to its knees for a brief period.

MT-Blacklist has now been disabled as part of an ongoing investigation into the exact cause. Without it, comments are disabled too. Like you, we look forward to getting Winds of Change.NET fully operational again, with the team and our platform wired together and going full-tilt boogie for freedom and justice.

UPDATE: Re: the exact cause(s). We've done some checking:

It may be that the server load caused by MT-Blacklist's "display suppression" feature is a capacity killer for sites with as many comments as we have (8500+):

"When the plugin is active, all comment and trackback content is compared to your blacklist. Posting of comments or trackbacks with blacklisted content will be blocked and all existing ones in the system will be omitted from MTComments and MTPings listings as well as MTEntryCommentCount. This control is useful if you are experiencing troubles. Think of it as the big red lever on the wall."

Those omissions require the system to scan a LOT of comments each time, something Jay Allen confirmed in an email to me tonight. WizBang has a hack to fix the problem, but Jay notes:

"The new version should be ready tomorrow. Not only should it be faster and more efficient, but it will also give you a choice on whether you want each feature. That means you could keep post and ping filtering on yet turn off old comment filtering. Should help your problem entirely."

MT-Blacklist v1.1 sounds promising. If you need other measures to protect your blog, we have a roundup of alternatives and complementary measures here.

It's also likely that we'll make some moves with Server-Side Includes to lessen the CPU thrash caused by having things like Category Listing Links and Recent Posts available on each page, plus very flexible archiving (Individual posts to make our briefings printable, by Date because people are used to that, and by Category so you can follow our coverage over time).

While some of these problems are a function of our growing scale, we're hoping that others will learn from our experiences and improve their own blogs in these ways. Not only will we keep you posted every step of the way, therefore - when we're done, we'll offer some tutorials that share our experiences and code fragments.

Join the effort! Anyone else out there with advice, thoughts, or comparative experiences to share is strongly encouraged to email joe, at windsofchange.net.


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