I tend to leave my IDEA open (at work) overnight, usually for days at a time. I've noticed that it becomes very slow and unresponsive after a while. Typing becomes very slow and I can see the cpu usage spiking any time I do anything in the editor.
I don't recall this happening on IDEA 11, but it has been a long time since i've used it. This is IDEA Ultimate 12.1.6, but the problem has existed for at least a couple of minor release.
Anyone have any suggestions?