Turning off DVI monitor causes performance glitches

Originator:owenimholte
Number:rdar://10874774 Date Originated:15-Feb-2012
Status:Closed Resolved:
Product:Mac OS X - Mac Pro Product Version:10.7.3
Classification:UI/Usability Reproducible:Always
 
Summary:
When I have a Westinghouse 1080p DVI monitor plugged in to my Mac Pro (secondary to my mini-displayport 27" display) but switched off the system experiences slowness for ~200ms every 3 seconds. During this time the mouse stops moving smoothly and the computer is generally unresponsive.

Steps to Reproduce:

1. Connect Apple Cinema Display to mini-Display Port.
2. Connect other display to the DVI port.
3. Turn off the secondary (DVI) display with its built in power button.
4. Observe SystemUIServer CPU usage spike and mouse stutter.

Expected Results:

Turning off a display should not cause a performance issue.

Actual Results:

Mouse jumps and UI lag is common on a constant basis when a display is connected but disabled.

Regression:

This has been present since Snow Leopard. I believe it also happens from the login screen.

Comments


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