I've been having this issue as well, typically on monk, while Rushing Jade Wind is up.
AutoBar sits at 65.41mb memory usage while idle, but when I use RJW, it starts shooting up dramatically (about 10mb/s), eventually topping the list at >130mb usage. Occasionally, it will reset back to ~60mb.
If I disable the 'Extras' bar and reload, the problem goes away in my case. But if I re-enable it, the memory usage does as described above.
I'll keep trying to isolate my problem and update you.