Date: Tue, 22 Oct 2002 14:46:12 -0500 From: Dan Nelson <dnelson@allantgroup.com> To: Terry Lambert <tlambert2@mindspring.com> Cc: Danny Braniss <danny@cs.huji.ac.il>, Poul-Henning Kamp <phk@critter.freebsd.dk>, freebsd-hackers@FreeBSD.ORG Subject: Re: malloc Message-ID: <20021022194612.GA7165@dan.emsphone.com> In-Reply-To: <3DB5A73C.20513D50@mindspring.com> References: <E183u5Y-0003Yc-00@cse.cs.huji.ac.il> <3DB50A5A.F87EDA78@mindspring.com> <20021022153347.GA92973@dan.emsphone.com> <3DB5A73C.20513D50@mindspring.com>
next in thread | previous in thread | raw e-mail | index | archive | help
In the last episode (Oct 22), Terry Lambert said: > Dan Nelson wrote: > > > The FreeBSD malloc uses anonymous pages mmap'ed off of /dev/zero. > > > > > > The Linux malloc uses pages added to the process address space via a > > > call to sbrk. > > > > Actually, on FreeBSD only the page directory is mmap'ed. Data > > returned to the user is allocated via sbrk. > > Please see: > > /usr/src/lib/libc/stdlib/malloc.c > > The only calls to sbrk have a 0 argument. This is only used to find > the segment end, so that the mmap's do not occur over top of anything > important. Ah, but take a look at the calls to brk, especially in map_pages() and free_pages(). -- Dan Nelson dnelson@allantgroup.com To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hackers" in the body of the message
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?20021022194612.GA7165>