On Mon, Jun 05, 2006 at 10:48:09AM -0500, Jeremy White wrote: > I am running in to some strange memory errors when trying to optimize a JVM. > When I set the min and max to 1.5gb and start the JVM, I immediately get an > OutOfMemoryError. If I pull it back to 1.2gb or so, it works fine. The > amount of physical memory in this machine is 4gb, and nothing else is really > running on it. The machine is running RHEL 2.1, kernel 2.4.9-e.65smp. > > We have another server that we just upgraded the OS on, to RHEL 3, kernel > 2.4.21-40.ELsmp. On that server, the JVM starts fine with a 1.5gbmin/max. > > I suspect this has to do with the way the kernel manages memory. I know I > have read that you can not give a JVM over 2gb of memory in Linux, but I am > not even getting close to that. Since this works on the newer kernel, maybe > its something thats compiled in, but I was hoping it was a configuration > that could be changed. > > Anyway, I would just like to get some ideas because I really would like to > know more about tuning the kernel for memory management, and I would like to > know why these JVMs are throwing these errors - mostly out of curiousity - Ignored: as > to how things work. What JVM and what version? Have you tried SUN, IBM and JRockit? Is this for an application server, or a J2SE application? From the memory limits I infer you are running on i386. Are both machines identical? Are both JVMs indentical? florin Florin, Thanks for the quick response. I am currently using the Sun JVM version 1.4.2_08. This is for a Tomcat application server version 4.1.31 . Yes both machine are identical except for the OS. One is RHEL 3, kernel 2.4.21-40.ELsmp and the other is RHEL 2.1, kernel 2.4.9-e.65smp. Jeremy -------------- next part -------------- An HTML attachment was scrubbed... URL: http://mailman.mn-linux.org/pipermail/tclug-list/attachments/20060605/cff6d279/attachment.htm