Using mmap(2) with a hint address

[Ganael LAPLANCHE]

Hi Artem, Tijl,

On Tue, 20 Dec 2011 09:27:43 -0800, Artem Belevich wrote
> Something like that. [...]
> These days malloc() by default uses mmap, so if you don't force it to
> use sbrk() you can probably lower MAXDSIZE and let kernel use most
> of address space for hinted mmaps.
> [...]

On Tue, 20 Dec 2011 18:45:08 +0100, Tijl Coosemans wrote
> I don't know about NetBSD but Linux maps from the stack 
> downwards when there's no hint and FreeBSD maps from the 
> program upwards. [...]
> malloc(3) used to be implemented on top of brk(2) so the size was
> increased on amd64 so you could malloc more memory. Nowadays malloc
> can use mmap(2) so a large datasize isn't really needed anymore.

I will use setrlimit(2) to lower datasize then.

Thanks a lot for your time and explanations,
Best regards,

--
Ganael LAPLANCHE <ganael.laplanche at martymac.org>
http://www.martymac.org | http://contribs.martymac.org
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