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From: Erik Groeneveld <erik@cq2.nl>
Date: Thu, 14 Apr 2011 10:02:00 -0000
Message-ID: <BANLkTin--js79v++2OjAtpsNuoPi5AUBoQ@mail.gmail.com>
Subject: Re: GC leaks debugging
To: Andrew Haley <aph@redhat.com>
Cc: "Boehm, Hans" <hans.boehm@hp.com>, "java@gcc.gnu.org" <java@gcc.gnu.org>
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On Thu, Apr 14, 2011 at 10:43 AM, Andrew Haley <aph@redhat.com> wrote:
>> I will be looking into getting USE_MMAP to work, as I think that would
>> be a more definite solution. =C2=A0However if I enable it, it segvs.
>>
>> Are there any specific obstacles for USE_MUNMAP when used in GCJ, or
>> should it just work?
>
> MUNMAP, hmm. =C2=A0I don't know; it should work but there's no experience.

Ok, that is important information if I start debugging: it is perhaps
only a bug, not a fundamental problem per se.

> Why do you want to munmap, anyway? =C2=A0Are you running out of swap spac=
e?

Well, I assume that if the GC unmaps a page (hblk), it can always be
mapped at any other location when a new block is needed, effectively
circumventing fragmentation completely.  However, I did not dive into
the exact usage of mmap and I assumed a straightforward way of
utilization of mmap by the GC.  I might be wrong....