Eclipse performance tuning for multiple CPUs and lots of memory?

I have a dual quad core machine with 12 Gigs of memory on which I run eclipse, does an开发者_运维知识库yone know what JVM Options will give the most responsive / performant experience?

I am currently running:

-Xms256m -Xmx2048m -Xss2m -XX:PermSize=128m -XX:MaxPermSize=384m

Would changing -Xmx to 4096 give better performance? Or is there some point when more memory will deteriorate performance?

Also can I have a garbage collector running on a separate core to stop lags in the UI during GC?

The most important thing to make sure is that you are running 64-bit version of Eclipse on 64-bit version of JVM. Your are already allocating more memory than I have ever seen allocated to Eclipse. Unless you have ginormous code base loaded in Eclipse, chances are that you will not come close to hitting that limit. You can keep an eye on Eclipse memory consumption in your OS process monitor. If you see it approaching the limit, then you know that you can give it more memory.

JVM will automatically use all available cores. Eclipse is highly multi-threaded. There are no facilities to pin Java threads or the GC to specific cores.

If you are seeing UI lag on a modern JVM, it is not due to GC unless you ran out of memory and GC must pause the process.