I agree, it's always a good idea to let the JVM do what it is supposed to do instead of creating a growing overhead. The only exception to that rule is if you think you'll reach 1024 MB, but as you say yourself, 512 seems to do fine as -Xms.
btw, here is an article that goes into detail (ratio's etc.) using jvm 1.4.2 http://java.sun.com/docs/hotspot/gc1.4.2/index.html Q > -----Original Message----- > From: Dale, Matt [mailto:[EMAIL PROTECTED] > Sent: 20 April 2005 15:24 > To: Tomcat Users List > Subject: RE: Heap not expanding beyond -Xms512m > > > > This is expected behaviour. The heap will not grow if the > memory required can be gained through a garbage collection. > The heap will only grow if after a garbage collection it > still cannot allocate the required memory or is over a > certain percentage (I forget what the default is). > > I would suggest that you don't in fact need 512MB if your app > runs fine with no OOM in 512MB. > > If you really want to use the full 1GB the you'll have to use > -Xms as you suggested. > > Ta > Matt > > -----Original Message----- > From: Guillaume Lahitette [mailto:[EMAIL PROTECTED] > Sent: 20 April 2005 13:54 > To: tomcat-user@jakarta.apache.org > Subject: Heap not expanding beyond -Xms512m > > > Hello Tomcat-oids, > > I'd really appreciate any help with this...Thanks in advance. > > We've been running performance tests against Tomcat 4.1.26 on > Linux and Windows. We've tuned heap sizes to -Xms512m -Xmx1024m. > > Monitoring the JVM memory usage with a daemon thread calling > Runtime.getRuntime().freeMemory() / totalMemory() / > maxMemory(), we've noticed memory was never expanded beyond > 512MB. Instead, when usage was getting close to 512MB, we > could see the garbage collector kick in. We never got OOM errors. > > Can anyone share experiences about this? Do I have to use > -Xms1024m -Xmx1024m (which seems to defeat the purpose of > having ms and mx...)? > > Guillaume > > --------------------------------------------------------------------- > To unsubscribe, e-mail: [EMAIL PROTECTED] > For additional commands, e-mail: [EMAIL PROTECTED] > > > --------------------------------------------------------------------- > To unsubscribe, e-mail: [EMAIL PROTECTED] > For additional commands, e-mail: [EMAIL PROTECTED] > > --------------------------------------------------------------------- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
