From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Thu, 24 Feb 2000 16:15:30 +0100 From: Jamie Lokier Subject: Re: mmap/munmap semantics Message-ID: <20000224161530.G7129@pcep-jamie.cern.ch> References: Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: ; from Richard Guenther on Thu, Feb 24, 2000 at 04:03:35PM +0100 Sender: owner-linux-mm@kvack.org Return-Path: To: Richard Guenther Cc: kernel@kvack.org, "Stephen C. Tweedie" , Linux Kernel List , glame-devel@lists.sourceforge.net, Linux-MM List-ID: Richard Guenther wrote: > Oops, so I misread the code in drivers/char/mem.c ... well, so how can I > get the same effect as for the private mapping? Not at the moment, I > think? So memset should be faster than reading from /dev/zero? Try them both. /dev/zero may be faster eventually, once kiobufs do clever things. For the moment they should be about the same speed apart from syscall entry cost, so zeroing a large region would be fine with /dev/zero, and for a small region even when kiobufs are working, you probably don't want the overhead of messing with page tables for a small region. enjoy, -- Jamie -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux.eu.org/Linux-MM/