Peter Johnson [https://community.jboss.org/people/peterj] created the discussion "Re: Options for CMS and G1 Collectors" To view the discussion, visit: https://community.jboss.org/message/722530#722530 -------------------------------------------------------------- Actually, this is a bad idea based on testing that i haved done. Two reasons: 1) The pauses during CMS and G1 collections (yes, there are pauses - two of them) are about as long as the pause caused by minor collection. 2) While CMS and G1 run, they are using up one entire processor/core at 100% because they are memory and processor intensive. You want those collectors to run as rarely as possible. If you tenure every object that lives through a minor collection, then you are going to run CMS/G1 more often and thus will more often lose the use of a core to process business requests. See this white paper: Java Garbage Collection Performance Analysis 201 at http://www.cmg.org/cgi-bin/search.cgi?q=java+peter+johnson&x=30&y=10 http://www.cmg.org/cgi-bin/search.cgi?q=java+peter+johnson&x=30&y=10 (I worked with a beta version of G1, so take the stability warnings with a grain of salt) -------------------------------------------------------------- Reply to this message by going to Community [https://community.jboss.org/message/722530#722530] Start a new discussion in Performance Tuning at Community [https://community.jboss.org/choose-container!input.jspa?contentType=1&...]

Peter Johnson [https://community.jboss.org/people/peterj] created the discussion "Re: Options for CMS and G1 Collectors" To view the discussion, visit: https://community.jboss.org/message/722560#722560 -------------------------------------------------------------- As I mentioned I worked with a beta version of G1 so the white paper (which was written in 2009) doesn't have the latest options. By the way, the white paper that discusses G1 is titled "Reducing Java Garbage Collection Pause Times" (it also covers CMS). Why are you trying to log onto the web site, you don't need to. The link show take you to a search results page that shows all of my white papers. -------------------------------------------------------------- Reply to this message by going to Community [https://community.jboss.org/message/722560#722560] Start a new discussion in Performance Tuning at Community [https://community.jboss.org/choose-container!input.jspa?contentType=1&...]