Update: Joseph Scott has provided some information in the comments below, and the problem is most likely on the blog server side, not with Akismet. Thanks Joseph for explaining that. Akismet is not struggling.
Recently I have seen a lot of spam hit the moderation queue on my blog. At the same time there is a warning that;
Akismet has detected a problem. A server or network problem prevented Akismet from checking 1 comment. It has been temporarily held for moderation and will be automatically re-checked in 18 mins.
Currently the spam that keeps getting through as a result of this is a message by some called jiggamuffin. The IP address is always different, so this appears to be a pretty sophisticated and automated spammer. Could one persistent spammer actually be the cause of the problems? With so much spam being sent at any one time, maybe they cause the Aksimet servers to fail which means some spam may sneak through.
Now, everything on my blogs is moderated (although this may have to change depending on the detailed terms and conditions of a particular insurance policy, still waiting on the legal chaps on that one) so maybe, possibly, on some blogs these messages are getting through…..
Although it seems that when Akismet fails it holds everything for moderation to play it safe. So that is good.