Why is NetBeans so slow? Here is a tip.
By kto on Feb 29, 2008
I use NetBeans 6 all the time on my Mac laptop and have learned how to configure it to run more effectively for me. NetBeans, like any Java application needs room to work, and the default memory settings for Java and NetBeans are usually not what I consider ideal. Of course how would they know what is ideal, you need to tell it. Granted my solution may not be ideal for others, but it's worth playing with. I'm using jdk5 update 13 on my Mac, but these same setting should apply to jdk6 also. And it's not just for The Mac or even NetBeans 6, this should work on any platform.
KellyMacBook<3> cat ~/.netbeans/6.0/etc/netbeans.conf netbeans_default_options="-J-Xms256m -J-Xmx512m -J-XX:PermSize=32m -J-XX:MaxPermSize=160m -J-Xverify:none -J-Dapple.laf.useScreenMenuBar=true -J-XX:+UseConcMarkSweepGC -J-XX:+CMSClassUnloadingEnabled -J-XX:+CMSPermGenSweepingEnabled"
Any change to this file will require a reboot (there should be one line in the file above, I had to break it up to get the blog to display it in a readable way).
Also, turn on the View->Toolbars->Memory to keep track of the NetBeans memory usage, clicking on it will force a GC, and you can get a feeling for how much memory your NetBeans session needs, making adjustments to the maximums above. And my recommendation is that the maximum (-J-Xmx) setting should never be more than the RAM on the machine minus 512m, or system memory thrashing may occur.
The above settings make a world of difference in the way NetBeans performs for me.