Hi guys, Did any one expereince the following problem? first let me tell my environment i use tomcat4-b7, on win2000, my jvm is jdk1.3 i have a simple jsp file which simply dynamically displays images the name of the images are dynamically created. when first time i acess my jsp file, it compiles and displays the images correctly without any problem, but for the second time it can't display whether i refresh the page or come back from another web address it jsut displays a white blank page without any error. Any idea about what is happening here, any logical expalantion? or is it a kinda metaphysical phenomena :) (joking) thanks for helping me have a trouble -free weekend :) yilmaz
----- Original Message ----- From: "Matt Egyhazy" <[EMAIL PROTECTED]> To: "Tomcat Users List" <[EMAIL PROTECTED]> Sent: Sunday, December 02, 2001 1:56 AM Subject: Re: Known Memory clean-up issues? > have you tuned the jvm settings? i had out of memory errors with 3.2.3 > version of tomcat after periods of heavy load until i tuned the jvm. > > matt > ----- Original Message ----- > From: "Randy Layman" <[EMAIL PROTECTED]> > To: "Tomcat Users List" <[EMAIL PROTECTED]> > Sent: Thursday, November 29, 2001 3:25 PM > Subject: RE: Known Memory clean-up issues? > > > > > > The best thing you can do is to find out where YOU are leaking > > memory. Tools like OptimizeIt are very useful for this type of issue. > Here > > are a few hints that might help you: > > * Sessions stick around for some time after the user leaves. If you > > have large amounts of data in the session, you might want to make your > > timeout smaller > > * Servlet instances stay around for very long amounts of time. > > Storing anything in static and/or instance variables of the servlet can > > consume memory for very long amounts of time > > * Static fields stay around for very long amounts of time, even if > > there are no more references to the classes > > > > Another tip, if you reduce the Heap size of your JVM then you can > > get the problem to happen quicker (since there's less memory available to > > leak). > > > > > > >From the JavaDoc on java.lang.OutOfMemoryError: > > "Thrown when the Java Virtual Machine cannot allocate an object because it > > is out of memory, and no more memory could be made available by the > garbage > > collector." > > > > Something is holding onto lots of memory. If your servlet is > > holding memory and a request comes it, its possible that the servlet is > > holding enough memory that Tomcat can't get the memory that it needs to > > service the request. > > > > Randy > > > > > > > -----Original Message----- > > > From: Denis Balazuc [mailto:[EMAIL PROTECTED]] > > > Sent: Thursday, November 29, 2001 3:42 PM > > > To: Tomcat Users List > > > Subject: Re: Known Memory clean-up issues? > > > > > > > > > Hi all > > > > > > Where would you recommend to use System.gc() in the context > > > of JSP pages ? > > > I guess it would be useless to intercept every single request > > > and hint the > > > system for garbage collection on each request ? > > > > > > (Now I quote) > > > "Also, before an OutOfMemory is thrown, the Garbage collector is > > > guarenteed to run, meaning that you really are using all of > > > your memory. I > > > would look at what you are doing in your code - I have > > > servlets that run for > > > weeks without eating up any significant portion of memory" > > > > > > I do have many times OutOfMemory exceptions thrown, although > > > we're not doing > > > *that* much.... > > > It happens quite randomly so it's very difficult to isolate > > > the problem. > > > Moreover, it even happens when fetching HTML pages from > > > Tomcat, without > > > using much JSP... > > > I'd like to find a place to catch that error to take action > > > (like restarting > > > Tomcat) but the only way we have found is to monitor the server and > > > automatically restart it when it fails to respond. > > > > > > Any guidance to solve the problem would be appreciated ;-) > > > > > > Thanks > > > Denis Balazuc > > > > > > > > > ----- Original Message ----- > > > From: "Yoav Shapira" <[EMAIL PROTECTED]> > > > To: "Tomcat Users List" <[EMAIL PROTECTED]> > > > Sent: Thursday, November 29, 2001 03:07 PM > > > Subject: Re: Known Memory clean-up issues? > > > > > > > > > > Howdy, > > > > > > > > > Any harm in forcing garbage collection to run? > > > > > > > > You cannot force garbage collection to run, only suggest it to the > > > > JVM via methods like System.gc(). If you're having difficulty > > > > tracking down memory usage, try a profiler like OptimizeIt that has > > > > entire memory trees. > > > > > > > > In addition, you can use parameters like hprof and verbosegc on > > > > the java command line to assist you in monitoring garbage > > > collection. > > > > > > > > Yoav Shapira > > > > > > > > -- > > > > To unsubscribe: > > > <mailto:[EMAIL PROTECTED]> > > > > For additional commands: > > > <mailto:[EMAIL PROTECTED]> > > > > Troubles with the list: > > > <mailto:[EMAIL PROTECTED]> > > > > > > > > > > > > > -- > > > To unsubscribe: <mailto:[EMAIL PROTECTED]> > > > For additional commands: <mailto:[EMAIL PROTECTED]> > > > Troubles with the list: <mailto:[EMAIL PROTECTED]> > > > > > > > -- > > To unsubscribe: <mailto:[EMAIL PROTECTED]> > > For additional commands: <mailto:[EMAIL PROTECTED]> > > Troubles with the list: <mailto:[EMAIL PROTECTED]> > > > -- > To unsubscribe: <mailto:[EMAIL PROTECTED]> > For additional commands: <mailto:[EMAIL PROTECTED]> > Troubles with the list: <mailto:[EMAIL PROTECTED]> > > -- To unsubscribe: <mailto:[EMAIL PROTECTED]> For additional commands: <mailto:[EMAIL PROTECTED]> Troubles with the list: <mailto:[EMAIL PROTECTED]>