This looks to me is because of larger default young generation size in newer java releases - see http://docs.oracle.com/javase/6/docs/technotes/guides/vm/cms-6.html#heap_size. I can see looking at your GC logs, around 6G space being used for young generation (though I do not see logs related to minor collection). That means for the same given number of objects, you have smaller old generation space and hence old generation collection can no longer perform well.
It is unfortunate that such changes are made in java and that causes previously working applications to fail. My suggestion is to not depend on default young generation sizes any more. At large JVM sizes, the defaults chosen by the JDK no longer works well. So I suggest protecting yourself from such changes by explicitly specifying young generation size. Given my experience of tuning GC at Yahoo clusters, at the number of objects you have and total heap size you are allocating, I suggest setting the young generation to 1G. You can do that by adding -XX:NewSize=1G -XX:MaxNewSize=1G Let me know how it goes. On Sat, Dec 22, 2012 at 5:59 PM, Edward Capriolo <edlinuxg...@gmail.com>wrote: > 6333.934: [Full GC 10391746K->9722532K(17194656K), 63.9812940 secs] > -- http://hortonworks.com/download/
