G1 is still under active development, but even with ideal implementation it wouldn't shine best performance Reason 1. G1 is using SATB write barrier which is m

G1 is still under active development, but even with ideal implementation it wouldn't shine best performance Reason 1. G1 is using SATB write barrier which is more expensive than crad marking barrier other HotSpot's collectors are using Reason 2. G1 have to use STW pause to move object around. E.g. if your heap is fulled in half we life objects, you have to physically move 1MiB live data in memory to reclaim 1MiB of free space, cleaning sparse regions first will effectively reduce this proportion but G1 is still have to work very hard to reclaim each meg of free space If you need low pause GC in JVM today. use concurrent mark sweep http://java.dzone.com/articles/how-tame-java-gc-pauses http://java.dzone.com/articles/how-tame-java-gc-pauses http://aragozin.blogspot.com/2011/07/gc-check-list-for-data-grid-nodes.html http://aragozin.blogspot.com/2011/07/gc-check-list-for-data-...