Hi Team, Recently I am seeing concurrent mode failure errors in my Verbose GC logs. For the same I have set NewSize to 512MB, still I am seeing concurrent mode failure in the Verbose GC logs
62230.611: [ParNew (promotion failed) Desired survivor size 32768 bytes, new threshold 0 (max 0) : 28481K->28481K(28608K), 0.0483728 secs]62230.659: [CMS (concurrent mode failure) Also Garbage collection is causing some large pauses. The largest pause was 121239 ms. : 1255376K->215461K(2068480K), 121.1880176 secs] 1283830K->215461K(2097088K)Heap after gc invocations=12320: par new generation total 28608K, used 0K [0x68800000, 0x6a400000, 0x6a400000) eden space 28544K, 0% used [0x68800000, 0x68800000, 0x6a3e0000) from space 64K, 0% used [0x6a3e0000, 0x6a3e0000, 0x6a3f0000) to space 64K, 0% used [0x6a3f0000, 0x6a3f0000, 0x6a400000) concurrent mark-sweep generation total 2068480K, used 215461K [0x6a400000, 0xe8800000, 0xe8800000) concurrent-mark-sweep perm gen total 88496K, used 55091K [0xe8800000, 0xede6c000, 0xf8800000) } , 121.2390524 secs] Following is my JVM argument -server -verbose:gc -Xmx2048m -Xms2048m -XX:NewSize=512m -XX:MaxNewSize=512m -XX:MaxPermSize=256M -XX:+UseConcMarkSweepGC -XX:+UseParNewGC -XX:+CMSParallelRemarkEnabled -Dsun.rmi.dgc.client.gcInterval=3600000 -Dsun.rmi.dgc.server.gcInterval=3600000 -XX:+DisableExplicitGC -XX:+HeapDumpOnOutOfMemoryError -XX:+HeapDumpOnCtrlBreak -XX:+PrintGCTimeStamps -XX:+PrintHeapAtGC -XX:+PrintClassHistogram -XX:+PrintGCDetails -XX:+PrintTenuringDistribution Tomcat Version 6.0.36 JDK Version Sun HotSpot 1.5.0.22 CPU Number of Physical processor 1 Number of Virtual processor 7 RAM 6144MB OS SunOS 5.10 Generic_147440-09 sun4v sparc sun4v Do you have any idea how to tune it further? Regards, Vidyadhar
