Comment 19 for bug 888039

I do see the same issue as you when performance drops - windows move 'jerkily', by not moving with the mouse and then suddenly jumping a large number of pixels all at once. The worst I have seen it get is that the mouse will move and the window not at all until a second after the mouse stops moving.

I use glxspheres because it provides numbers to describe the drop in performance. Typically glxspheres has much lower fps at the same time as the desktop becomes sluggish so I assume they are related.

I originally opened bug #861061 when the drop in performance had apparently become permanent, ie persisting across reboots. At some point it automagically resolved itself but has returned a number of times since. I suspect they may be the same bug but Daniel says is experiencing a permanent drop in performance and wants to use 861061 to track this permanent drop in performance.