On Mon, Jan 3, 2011 at 3:10 PM, Pid <p...@pidster.com> wrote: > On 1/3/11 1:10 PM, Leon Rosenberg wrote: >> Actually no, in my understanding both are independent. I mean the gc >> doesn't start "to copy over" if young is full, it simply cleans young. >> However, >> to quote your article: "Old generation objects are objects that >> survived a few collections in the young generation area", and if >> objects managed to survive longer as they should in the young space, >> they might have been copied to old gen, despite the fact, that they >> are young generation objects by nature (meaning short lifetime). This >> theory is what I'm trying to check. > > Objects which survive collections in young generations will make their > way into the old generation, and then sit around for a long time waiting > to be collected.
Hello pid-ster, > > What are your memory settings currently and how are the generations divided? -Xmx12G -Xms12G -XX:PermSize=128M -XX:MaxPermSize=256M -XX:+DisableExplicitGC -verbose:GC -XX:+PrintGCDetails -XX:+PrintGCDateStamps -Xloggc:/.../tomcat/logs/gc_tomcat.log jmap says: Attaching to process ID 16969, please wait... Debugger attached successfully. Server compiler detected. JVM version is 14.2-b01 using thread-local object allocation. Parallel GC with 6 thread(s) Heap Configuration: MinHeapFreeRatio = 40 MaxHeapFreeRatio = 70 MaxHeapSize = 12884901888 (12288.0MB) NewSize = 2686976 (2.5625MB) MaxNewSize = 17592186044415 MB OldSize = 5439488 (5.1875MB) NewRatio = 2 SurvivorRatio = 8 PermSize = 134217728 (128.0MB) MaxPermSize = 268435456 (256.0MB) Heap Usage: PS Young Generation Eden Space: capacity = 4074897408 (3886.125MB) used = 1509410704 (1439.4862213134766MB) free = 2565486704 (2446.6387786865234MB) 37.04168603206219% used >From Space: capacity = 110755840 (105.625MB) used = 47330080 (45.137481689453125MB) free = 63425760 (60.487518310546875MB) 42.73371047522189% used To Space: capacity = 109314048 (104.25MB) used = 0 (0.0MB) free = 109314048 (104.25MB) 0.0% used PS Old Generation capacity = 8589934592 (8192.0MB) used = 6636110912 (6328.688537597656MB) free = 1953823680 (1863.3114624023438MB) 77.25449874997139% used PS Perm Generation capacity = 268435456 (256.0MB) used = 228667664 (218.07447814941406MB) free = 39767792 (37.92552185058594MB) 85.18534302711487% used > > How many processors do you have available and are you using CMS & > incremental mode? vm with 6 assigned cores and no to both. I also might add, that the amount of free space right now is much higher as during the peak times, when its usually below 1GB (more sessions, more caches). regards Leon --------------------------------------------------------------------- To unsubscribe, e-mail: users-unsubscr...@tomcat.apache.org For additional commands, e-mail: users-h...@tomcat.apache.org
