"Some cursory Googling suggests that Java's GC will suspend the main execution thread during each GC op" The (non-default) CMS and G1 GCs will do as much as th

"Some cursory Googling suggests that Java's GC will suspend the main execution thread during each GC op" The (non-default) CMS and G1 GCs will do as much as they can in background threads before they have to stop the world. For more information see http://www.oracle.com/webfolder/technetwork/tutorials/obe/java/gc01/index.html http://www.oracle.com/webfolder/technetwork/tutorials/obe/ja... and http://www.cubrid.org/blog/dev-platform/understanding-java-garbage-collection/ http://www.cubrid.org/blog/dev-platform/understanding-java-g.... I only know about this because I kept encountering long, GC-related pauses on my Minecraft server that went away when I switched to the concurrent mark-sweep collector. :)