UseConcMarkSweepGC vs UseParallelGC

Question

I\'m currently having problems with very long garbage collection times. please see the followig. My current setup is that I\'m using a -Xms1g and -Xmx3g. my application is using

Answer 1

Your heap is too small. The pause is so large because it's busy repeatedly scanning the entire heap desperately looking for anything to collect.

You need to do 1 or possibly more of the following;

• find and fix a memory leak
• tune the application to use less memory
• configure the JVM is use a bigger heap

Are you tied to 1.4.2 for some reason? GC implementations really have moved on since then so you should consider upgrading if possible. I realise this may be a non trivial undertaking but it's worth considering anyway.