Eden space is not empty after a Full GC?

[Neo Jia]

On 5/14/07, Y Srinivas Ramakrishna <Y.S.Ramakrishna at sun.com> wrote:
>
>
> Neo Jia wrote On 05/14/07 09:00 AM,:
>
> > hi,
> >
> > I just found that for the generational mark-sweep garbage collector,
> > after a full GC, the eden space may not be empty.
>
> That would usually be the case because of  bin-packing
> issues with the sliding compaction that might prevent a large
> object in Eden from being "slid" into the available space
> in old gen or in the survivor space. It'll usually be the case
> then that your are running with memory quite tight (or
> with a huge Eden and very large objects).

Could you point me to the code where the full GC found it cannot slide
this huge chunk?

Thanks,
Neo

>
> Are there other situations where you see a non-empty Eden
> following a mark-compact full collection?
>
> >
> > Is there any implementation concern for this? Can I force the full GC
> > to clean the eden space?
>
>
> A full gc would do a mark-compact collection.
>
> -- ramki.
>
> >
> > Thanks,
> > Neo
>
>
> --
>
> ----------------------------------------------------------------------------
> Y. Srinivas Ramakrishna               HotSpot JVM
> Sun Microsystems, Inc., USCA 22-123   CSG / Sun Software
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> Santa Clara, CA  95054, U.S.A.        Y dot S dot Ramakrishna at Sun dot COM
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