If you say load is constant, seems to me that threads are stuck for some reason and tomcat create chunk of another. Thread dumps can provide answer to what are stucked threads waiting for.
Thread dumps can be taken for example with jconsole, which is part of jdk. Martin 2009/11/12 Goldsmith, Neil J. (Neil) <ne...@avaya.com>: > We are using Tomcat 5.5 to run high load through our servlets for about > 24 hours. The tests run a constant load and repeat the same set of > tests over and over. We are using perf mon to keep an eye on various > counters in Tomcat. > > We find after about 8 hours, we see this huge jump in thread count, > memory and handles inside Tomcat. All at once, we about double these > values. This happens over a very short time span, just a few minutes. > We don't drop back down to our old levels, but continue on at these new > levels without gaining and then another jump will occur about 6 hours > later (the time span is not consistent). That graph of threads, total > mem and handles for this behavior looks like a staircase. > > Looking at logs from our servlets, there is no unexpected behavior > during these huge jumps. They are chugging along handling the traffic > as expected and don't have any delays or out of the ordinary behavior. > > Does this sound like a GC issue? these are the settings we invoke TC > with. > JAVA_OPTS="-server -Xmx1024M -XX:+UseConcMarkSweepGC -XX:+UseParNewGC > -XX:ThreadStackSize=512" > > What is the best tool we can use to gather better information around the > problem, both free and for fee? > > thank you, > Neil > > --------------------------------------------------------------------- To unsubscribe, e-mail: users-unsubscr...@tomcat.apache.org For additional commands, e-mail: users-h...@tomcat.apache.org
