The VM does return memory, at least some GCs. How much and when is up to the GC. The 30-60% rule is very simplistic and can be improved upon if Xmx should go higer by default.
Current heuristic for memory release isn't good if you remove Xmx. I don't claim it is and I would never suggest to remove Xmx in the GC's current shape. But GC logic for returning memory could be made to return more quickly if memory gets low in the OS. Of course that work needs to be made first, then Xmx should be made optional. Cheers, Mikael On Aug 15, 9:58 am, Kirk <[email protected]> wrote: > The graphs are from VisualVM and the views are of Java Heap. The graphics > very nicely show Java heap utilization and the collector resizing heap space > to adapt. I just skimmed skimmed but if the author is claiming that memory is > being returned to the OS and this is proof, he's mistaken. It does *not* show > memory being returned to the OS. > > Regards, > Kirk > > On Aug 15, 2011, at 9:42 AM, Mikael Grev wrote: > > > > > > > > > Maybe this clears some things up regarding returning memory to the OS. > > >http://www.stefankrause.net/wp/?p=14 > > > Cheers, > > Mikael > > > -- > > You received this message because you are subscribed to the Google Groups > > "The Java Posse" group. > > To post to this group, send email to [email protected]. > > To unsubscribe from this group, send email to > > [email protected]. > > For more options, visit this group > > athttp://groups.google.com/group/javaposse?hl=en. -- You received this message because you are subscribed to the Google Groups "The Java Posse" group. To post to this group, send email to [email protected]. To unsubscribe from this group, send email to [email protected]. For more options, visit this group at http://groups.google.com/group/javaposse?hl=en.
