hi, Chuck.Caldarale I referenced to these two links http://blogs.sun.com/fkieviet/entry/classloader_leaks_the_dreaded_java http://blogs.sun.com/fkieviet/entry/how_to_fix_the_dreaded and do as the blog tolds, but failed to find the reason of the oom of my app... thanks though..
by the way, do you have the the jhat the articals mentioned? I went to the jdk/bin, but the jhat there seems not work as the author mentioned. 2010/11/23 Daniel Baktiar <dbakt...@gmail.com> > hi charles, > > please allow me to disagree to that "hanging onto reference" as the main > issue. > > permgen space is garbage collector's specific issue, not general "hanging > onto reference issue". it is caused by redeployment, which is the metadata > for classes, marked to be permanent generation by the hotspot garbage > collector. when you deploy new classes, the class loader will introduce > memory usages that will also marked as permanent generation. > > permgen is oracle hotspot specific implementation issue. you won't get it > when you run on oracle jrockit (which performs just in time compilation), > for example. > --- > daniel baktiar > http://savinggaia.tritiumapps.com - saving the planet is everyone's > business! > > > > > On 23 November 2010 14:10, Caldarale, Charles R > <chuck.caldar...@unisys.com>wrote: > > > > From: xu cheng [mailto:xcheng....@gmail.com] > > > Subject: Re: OutOfMemoryError some time on some tomcat!!!!1 > > > > > I just kept redeploying apps , and the perm gen keep > > > growing each time I deploy the same app. and when I > > > undeploy the app, the perm gen didn't clean the garbage > > > > Exactly the situation I suggested the other day: you have something > that's > > hanging onto a reference to an object from your webapp classes, > preventing > > the old webapp deployment from being garbage collected. Again, read > this: > > > > http://wiki.apache.org/tomcat/FAQ/Memory > > > > Also, take a look at these: > > > > http://blogs.sun.com/fkieviet/entry/classloader_leaks_the_dreaded_java > > http://blogs.sun.com/fkieviet/entry/how_to_fix_the_dreaded > > > > - 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. > > > > >
