Zoom (Accessibility feature) is extremely slow with multiple monitors [OSX 10.10]
When connecting an external display to my Laptop and using the "Ctrl + Scroll" functionality for accessibility zooming, the display/graphics are extremely slow.
An estimate of FPS would be sub 1FPS. The machine becomes unresponsive and is unusable for a minute or so, until I can get it zoomed back out, and it begins responding normally.
This is very disruptive, as its a feature I use often.
The same laptop on OSX 10.9 did not exhibit this issue.
Hardware: MacBook Pro 13" Retina Mid 2014, 16GB Ram
Software: OSX Yosemite 10.10
System Information: http://cl.ly/image/0H1p032w0M0w
Reproduction steps:
1. Enable CTRL+SCROLL zoom functionality in System Preferences > Accessibility
2. Connect external monitor (Display port cable)
3. Hold CTRL and Scroll to zoom
4. System becomes slow, graphics slow, showing < 1 FPS without any other applications running
MacBook Pro with Retina display, OS X Yosemite (10.10)