Did you see allen's reply to me above? ( http://dw-dev-training.dreamwidth.org/32468.html?thread=235476#cmt235476 ) Apparently there was a nested call somewhere that caused it to change from scanning n comments to n^2 comments, which is what really sucked up the time. I'm not great at following this code in particular so I can't see it myself, but that would explain the biggest delay in this case.