Re: using more physical memory?

From: Chris Kantarjiev (cak+news_at_dimebank.com)
Date: 06/21/05 

Date: Tue, 21 Jun 2005 11:11:32 -0700

tedu wrote:
> for the long answer, grep MAXDSIZ in the kernel. basically, it sets
> the size of the heap, which can't be used for other things like mmap().
> when this came up two weeks ago, the guy tried it and later told me
> "yeah, it didn't work too well". your experience may be different, but
> you're on your own.
> http://marc.theaimsgroup.com/?t=111731093400001&r=1&w=2
>

OK, I'll take that as an answer, thanks.

I took a different tack. Cursory reading of malloc.c led me to believe that it
uses mmap to allocate its pages if they're pagesize or more. I wrote a simple
program and found that wasn't actually true - despite the fact that there's an
internal function called "map_pages", it uses brk() to get those pages.

Perhaps a future edition of malloc() could take an option use mmap() to those
pages...

Thanks,
chris

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