Java HotSpot Virtual Machine

Hi guys,

Having some dramas with our web application. For the first 20 minutes of load testing our application (simulating real world usage), the application runs smoothly and we get frequent 30-100 millisecond garbage collects. After a certain length of time load testing our webapp, the application starts to pause for 3-5 seconds at a time. It pretty much stays like this going forward. Even when I reduce the load to 1/4th it carries on. If i stop all load, wait 5 mins and then start on 1/4th again, it does exaclty the same thing...

Application time: 22.0385040 seconds
6881.710: [GC 6881.710: [ParNew: 329024K->329024K(339264K), 0.0000391 secs]6881.710: [Tenured: 511676K->512401K(699072K), 3.2432927 secs] 840700K->512401K(1038336K), 3.2437477 secs]
Total time for which application threads were stopped: 3.2550032 seconds
Application time: 21.1843142 seconds
6906.191: [GC 6906.191: [ParNew: 329024K->329024K(339264K), 0.0000319 secs]6906.191: [Tenured: 512401K->509482K(699072K), 5.0673806 secs] 841425K->509482K(1038336K), 5.0677913 secs]
Total time for which application threads were stopped: 5.1204544 seconds
Application time: 20.6077199 seconds
6931.964: [GC 6931.964: [ParNew: 329024K->329024K(339264K), 0.0000353 secs]6931.964: [Tenured: 509482K->509916K(699072K), 3.2153139 secs] 838506K->509916K(1038336K), 3.2157275 secs]
Total time for which application threads were stopped: 3.3133303 seconds
Application time: 3.6100249 seconds
6955.063: [GC 6955.063: [ParNew: 328966K->328966K(339264K), 0.0000351 secs]6955.063: [Tenured: 509916K->511211K(699072K), 3.2276527 secs] 838882K->511211K(1038336K), 3.2280768 secs]
Total time for which application threads were stopped: 3.2379824 seconds
Application time: 21.0743922 seconds
6979.366: [GC 6979.366: [ParNew: 328917K->328917K(339264K), 0.0000317 secs]6979.366: [Tenured: 511211K->512031K(699072K), 3.2287033 secs] 840128K->512031K(1038336K), 3.2291089 secs]
Total time for which application threads were stopped: 3.2300160 seconds
Application time: 22.5555653 seconds
7005.152: [GC 7005.152: [ParNew: 329024K->329024K(339264K), 0.0000327 secs]7005.152: [Tenured: 512031K->509476K(699072K), 4.7756908 secs] 841055K->509476K(1038336K), 4.7760826 secs]
Total time for which application threads were stopped: 4.7769728 seconds
Application time: 21.9363516 seconds


machine is a T1000 sparc

Java options are:

JAVA_OPTIONS=-Xmx1024m -Xms1024m -verbose:gc -XX:-BindGCTaskThreadsToCPUs -XX:ParallelGCThreads=4 -XX:+PrintGCDetails -XX:+PrintGCApplicationConcurrentTime -XX:+PrintGCApplicationStoppedTime -Xloggc:/log/stellent_jvm_garbagecollect.txt

JAVA_EXE=/local/jdk1.5.0_07/bin/java

Anyone got any ideas on how I could work out what is going wrong?