On Thu, 2006-01-05 at 11:49 -0800, Brian D. McGrew wrote: > I know this is the Fedora, not Java list; but I'm not getting any help > over there! > > Speaking from a hardware standpoint, we distribute our systems on Dell > PowerEdge 1800 Server machines and we're limited (by our own hardware) > to 512MB RAM. It stands to reason that these machines don't have very > beefy graphics support in them. Low end nVidia or ATI chipsets at best! > > We're doing some work in Java, running under Sun's JVM and driving the > graphics card with images while the CPU is at a decent load. As our > images grow in size the drawing slows down. The 640x480 stuff is good, > the 1280x1280 stuff is alright but the 2048x2048 is unusable. > > >From a hardware / (operating system) software standpoint, what would you > do to speed things up? I can't add memory; we don't have any open slots > to add in another graphics card and using a workstation model machine > with better graphics isn't a choice either. > > Any ideas??? Hi Brian, There is a lot you can do to tune the JVM for various loads and tasks. Have a look here: http://java.sun.com/performance/reference/whitepapers/tuning.html This paper talks about improvements made to the 1.4.2 VM. http://java.sun.com/j2se/1.4.2/reference/whitepapers/index.html#8 Try out the jvmstat tool - it will show you information about the runtime resource usage of the JVM. Are you using the latest Sun VM (JDK/JRE 5.0 Update 6)? Sun update their JRE and JDK regularly with bugfixes and performance improvements. You may wish to post the same question to a Java User Group list (not sure if you have done this). If you can't find one, try mine :) It has around 1000 members, and is a helpful group. http://groups.yahoo.com/group/ajug/ This forum at java.sun.com may be a good place to ask for help. http://forum.java.sun.com/category.jspa?categoryID=11 >From an O/S perspective, profile the memory use of the JVM, and try and remove any unnecessary apps competing for resources. Ie. disable all services that are not required, and turn off cron jobs that kick in to optimise things at various times (like prelink). It is likely your machines are swapping - try and trim the fat until they don't need to, if possible. Cheers, Ben
