Re: memory behavior to expect with gjdoc-0.7.6

[Robert Lougher]

On 12/5/05, Robert Lougher <address@hidden> wrote:
> Hi,
>
> On 12/5/05, Mark Wielaard <address@hidden> wrote:
> > Hi Fred,
> >
> > On Mon, 2005-12-05 at 12:32 -0500, address@hidden wrote:
> > > > Could you also run JamVM with -verbose:gc and send me the output?
> > > >
> > > Attached.
> >
> > Thanks. This seems to point out two things:
> >
> > 1) There is a huge allocation (2MB+):
> >   <GC: Alloc attempt for 2209016 bytes failed.>
> >   at this point in the code:
> >
> >    // REVIEW: Using max instead of average may allocate a very large
> >    // buffer.  Maybe we should do something more efficient?
> >    int remaining = in.remaining ();
> >    int n = (int) (remaining * maxBytesPerChar ());
> >    ByteBuffer out = ByteBuffer.allocate (n);
> >
> >  I believe that REVIEW note gives us a hint :)
> >
> > 2) JamVM has fragmented its heap so much that it cannot allocate such a
> >   block of data even though there is enough space in total:
> >   <GC: Largest block is 2087448 total free is 778822576 out of
> >    943718392 (82%)>
> >
> >   Or am I reading the output incorrectly?
> >
>
> This is what I was afraid of.  JamVM doesn't use handles so compaction
> is a non-trivial exercise.  However, I'd like to analyse the gc output
> myself, but I don't seem to have been sent it...
>

On second thoughts, it may have been rejected by gmail if the
attachment was too big (how big was it?).  Could you try compressing
it (if it wasn't)?

Thanks,

Rob.

> Rob.
>
> > Cheers,
> >
> > Mark
>