
How does one do that?
- Choose Lightroom > Preferences (Mac OS) or Edit > Preferences (Windows).
- Click the File Handling tab.
- In the Camera Raw Cache Settings area, experiment with a Maximum Size of 10.0 GB or more.
http://helpx.adobe.com …erformance-lightroom.html

I set mine at 20Gb and it helped some.
A SSD would be very nice though. One day I suppose.