I see odd behavior. Our tomcat setting is set for a max memory setting of 256Mb in our Development Environment. Yet it goes over 256Mb. Up to 290Mb. I assumed that it would never go over 256Mb in task manager. Is that correct? thanks
Answers Below as well... -----Original Message----- From: Caldarale, Charles R [mailto:chuck.caldar...@unisys.com] Sent: Monday, November 02, 2009 4:06 PM To: Tomcat Users List Subject: RE: Tomcat Memory and Garbage Collection questions... > From: Johnson, Trevin (Contractor) > [mailto:trevin.john...@occ.treas.gov] > Subject: Tomcat Memory and Garbage Collection questions... > > When we restart the tomcat service our tomcat memory is about 120Mb. It > keeps going up over the next few days util it reaches 700Mb and we have > to reboot the server. Why do you reboot? Is the server unresponsive? -We actually just restart Tomcat service and it goes back down to about 120Mb > 1.We do not see the memory going down for the tomcat service. Shouldn't > the memory go down as well as up over this timespan What are you using to show the memory usage? -We are using task manager to show Tomcat memory usage > 2.Should the memory get to maximum 768Mb and then go back down or get > recycled? Depends on what you're looking at. If it's Task Manager, it won't go down. If you're using JConsole to look at the heap, it should go up and down. > 3.Is this a bug or what is normal behavior for the tomcat memory? Depends; see above. > 4.. How do we implement garbage collection for our windows server(- > Xincgc)? Garbage collection is always present. Incremental GC can be useful to minimize pause times, but it is more overhead and has some restrictions on just what it can collect. Unless you really think you need that option, I wouldn't set it right now. I'd strongly recommend using JConsole to look at heap usage, then use a profiler if you find that the heap usage does not stabilize. You can also turn on -verbose:gc, and use jhat and jmap to do basic heap analysis. Some useful resources: http://java.sun.com/j2se/1.5.0/docs/guide/vm/gc-ergonomics.html http://java.sun.com/javase/technologies/hotspot/gc/index.jsp - Chuck THIS COMMUNICATION MAY CONTAIN CONFIDENTIAL AND/OR OTHERWISE PROPRIETARY MATERIAL and is thus for use only by the intended recipient. If you received this in error, please contact the sender and delete the e-mail and its attachments from all computers. --------------------------------------------------------------------- To unsubscribe, e-mail: users-unsubscr...@tomcat.apache.org For additional commands, e-mail: users-h...@tomcat.apache.org --------------------------------------------------------------------- To unsubscribe, e-mail: users-unsubscr...@tomcat.apache.org For additional commands, e-mail: users-h...@tomcat.apache.org
