How recent is your Satrina's Buff Frames? There was apparently a HUGE problem with its interactions with ButtonFacade, such that Satrina disabled BF support entirely.
I noticed I was getting huge pauses in raid when I would gain or lose a buff, and the more I gained or lost, the worse it was. In a raid, with procs going off all over the place, and totems going up and down and up and down, and people moving in and out of range, it was just unplayable. I disabled SBF, and that fixed it for me, got rid of the pauses completely, but it seems to be caused by ButtonFacade. That was one of the versions with ButtonFacade enabled. She's since disabled them, see here:
http://www.wowinterface.com/download...BF3.0Beta.html
I'm going to try the newer beta and see how that does. But I know that's been one big cause of slowdowns on my computer. Since you're seeing the same huge memory usage by BF, that might be the issue for you as well. I also noticed that it would get progressively worse and worse as we went along.
Hope that helps.