What happens if you *reduce* the allocated heap size - do you actually need that much Java heap? Native threads are created outside of the Java heap. You have 2G for (4 * 400) = 1600 threads plus the OS, or about 1 Mbyte per thread (this assumes no swap space). That may not be enough.
- Peter On 3 August 2010 15:21, Tomcat Novice <tomcat.nov...@gmail.com> wrote: > Hi, > > I hope someone can help me. I am new to tomcat and I have been encountering > issues where a particular tomcat instance/s are having large thread count > during load testing and results in a hung state. The error shown on the > browser is: java.lang.OutOfMemoryError: unable to create new native thread > (stack trace attached) > > Environment: > > OS: Windows 2003 64 bit > JDK 1.5 > 8GB Total Machine RAM > 4 Tomcat 5.5 instances running as a service on one Physical Server (each > Tomcat configured to use 1.5GB of Heap) 4 instances x 1.5GB = 6GB of Heap > 4 Identical servers configured the same way and load balanced > IIS Web Server front end (AJP Port configured) no maxThreads property is > set on server.xml for AJP port declaration. Per documentation ( > http://tomcat.apache.org/tomcat-5.5-doc/config/ajp.html), if no value is > set maxThreads are set to 200 > > Not all 4 servers are experiencing this problem. > > 1. Any ideas how I can resolve/isolate this problem? > 2. I know I need to do a thread dump but I am not familiar on how to > analyze thread dumps from Tomcat. Can you point me to documententation on > how I can analyze thread dumps from Tomcat? > 3. Also, can someone confirm if the thread dumps from JDK 1.5 are the same > as the Thread Dumps from a JDK 1.6? I seem to be getting different formats. > Can someone just confirm? > 4. If the maxThread is set to 200, why are the Tomcat instances utilizing > up to 400 Threads (see screenshot) > > Regards, > > Tomcat Novice > > > --------------------------------------------------------------------- > To unsubscribe, e-mail: users-unsubscr...@tomcat.apache.org > For additional commands, e-mail: users-h...@tomcat.apache.org >
