Eclipse can get a bit sluggish, especially when you’ve got the Scala and Maven plugins installed into it. I found the following website with some useful improvements you can make to the eclipse.ini file to speed it up. This works for Windows and Linux systems and will probably work with Mac as well. It give eclipse more memory so if you are running a dev machine with 4GB of RAM then this should work fine. The eclipse.ini file can be found in the root of the eclipse application folder.

The vmargs parameter as shipped uses these heap settings (at the bottom of the eclispe.ini file):

-Xms40m -Xmx364m

It needs to specify a larger heap and more stack.

-Xss8m -Xms800m -Xmx2048m -XX:NewSize=400m -server -XX:+DoEscapeAnalysis -XX:+UseConcMarkSweepGC

Adjust the max heap size (“mx”) to be sure that it fits in real memory. “ms” should be twice the “NewSize”.

Ref: http://projectfortress.sun.com/Projects/Community/wiki/Eclipse