On Wed, Jun 23, 2010 at 8:47 PM, Mrohs, Ray <ray.mr...@usdoj.gov> wrote: > Rob, > > Heap size is set to 500M/1000M. I've read recommendations to make default/max > the same number, but I would just be guessing at a value. It has grow close > to 800M at least once, but it always falls back to around the default size > and stays there most of the time. > > Ray
The suggestion to set min and max the same goes well with the folks who have plenty of memory and just want to avoid garbage collection... whether it applies to a shared resource environment needs to be seen (uh, measured..) When the minimum heap size is smaller than the maximum, JVM moves objects in the heap such that entire chunks of memory can be returned to Linux. This makes sense when peak usage is termporary because you avoid the JVM to sit on all the memory when it does not have to. But when the memory requirement is fairly constant, it would be a waste to give the chunk back and then ask for it again. I'm always suspicious about recommendations without motivation or measurements. If it really were the best setting, would we not expect the defaults to be like that? Rob -- Rob van der Heij Velocity Software http://www.velocitysoftware.com/ ---------------------------------------------------------------------- For LINUX-390 subscribe / signoff / archive access instructions, send email to lists...@vm.marist.edu with the message: INFO LINUX-390 or visit http://www.marist.edu/htbin/wlvindex?LINUX-390 ---------------------------------------------------------------------- For more information on Linux on System z, visit http://wiki.linuxvm.org/
