> From: Jim [mailto:[EMAIL PROTECTED] > Subject: Re: PermGen Out of memory exception > > To address your rhetorical question :) , this issue is a > mess to research.
Which is why it should be done before deployment... > it can be intimidating to be pointed at a 21 page > Sun white paper Try this one first: http://java.sun.com/j2se/1.5.0/docs/guide/vm/gc-ergonomics.html Unfortunately, it does not address class-heavy situations, such as app servers. > http://www.jroller.com/agileanswers/entry/preventing_java_s_java_lang, > which suggests upgrading Tomcat, or switching to JRockit, or > upgrading the JVM. Switching to JRockit only masks the problem temporarily, since it doesn't have a separate space for instances of java.lang.Class; do enough app reloads with JRockit, and you will run into the problem. We've also found other significant issues with JRockit, so I can't recommend it. > http://my.opera.com/karmazilla/blog/2007/03/15/permgen-strikes-back This one article is the source of much misinformation. It's unfortunate that the author has decided his conclusions are the only possible ones that explain the symptoms, regardless of reality. > The fallacy's just not obvious, and there's no simple authority > on this common issue. Well, actually there is - look at the HotSpot JVM code, which is freely available. Of course, there are side effects ("My brain hurts!" "It will have to come out." :-). > Perhaps the Tomcat FAQ on memory-issues could be fleshed > out/updated? This specific item is already in the Tomcat FAQ: "If you have a lot of servlets or JSP's, you may need to increase your permanent generation. By default, it is 64MB. Doubling [sic] it to be -XX:MaxPermSize=256m might be a good start." > an explicit contrary statement in the FAQ would be helpful This article linked to from "Your classloaders are not being garbage collected" seems to cover pretty much everything you've asked for. For reference, it points to the following location: http://opensource2.atlassian.com/confluence/spring/pages/viewpage.action ?pageId=2669 - 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 start a new topic, e-mail: users@tomcat.apache.org To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
