On 8/18/05, Jonathan Oexner <[EMAIL PROTECTED]> wrote: > My concern with the current used /current heap line is that, if the VM > decides to increase the heap size, you can't tell by looking at the > line whether heap size went up, or the GC freed up some memory.
I don't believe that is true. I've run probably 50+ tests against tomcat using JMeter to simulate 50-150 threads and monitoring tomcat. You can tell, since it's relative. As the JVM increases the heap, it attempts to maintain used memory to under 50%. Once the system hits the max heap, you're in trouble from my experience. I've worked on some pretty large sites that get 10Million+ page views. Generally speaking, you want the average heap used to be less than 50%. > > The rationale behind using the max heap size as the denominator is > just so that the memory used line depends *only* on the amount of > memory in use (well, that and the *max* heap size, which is constant > for our purposes). You can see the absolute heap usage. It has the > added benefit that both the heap size and the heap usage are on the > same scale, which means that you can see how close the memory usage > has to get before the JVM decides to grow the heap. > > Try it out. You might like it. ;) > I actually have tried in real applications, so that is my experience. It would be beneficial for you read up on how the JVM manages heap, since that doesn't match my experience or existing documentation. Is this based on real world loads and application? Or it is based pure on theory? I've mainly worked on large clusters, so my experience may be totally different than what you see. peter lin --------------------------------------------------------------------- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
