From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S263945AbTDNU2E (for ); Mon, 14 Apr 2003 16:28:04 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S263946AbTDNU2D (for ); Mon, 14 Apr 2003 16:28:03 -0400 Received: from zcars04e.nortelnetworks.com ([47.129.242.56]:21185 "EHLO zcars04e.nortelnetworks.com") by vger.kernel.org with ESMTP id S263945AbTDNU2A (for ); Mon, 14 Apr 2003 16:28:00 -0400 Message-ID: <3E9B1C8E.5030707@nortelnetworks.com> Date: Mon, 14 Apr 2003 16:39:42 -0400 X-Sybari-Space: 00000000 00000000 00000000 From: Chris Friesen User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:0.9.8) Gecko/20020204 X-Accept-Language: en-us MIME-Version: 1.0 To: "H. Peter Anvin" Cc: linux-kernel@vger.kernel.org Subject: Re: Memory mapped files question References: <002101c30239$fc0ae630$fe64a8c0@webserver> <8180000.1050330998@[10.10.2.4]> <20030414150759.GA14552@wind.cocodriloo.com> <11640000.1050332688@[10.10.2.4]> Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org H. Peter Anvin wrote: > Followup to: <11640000.1050332688@[10.10.2.4]> By author: "Martin J. > Bligh" In newsgroup: linux.dev.kernel > >>> Martin, something which was not mentioned last week (I've just checked). >>> >>> It's OK if we never write to disk unless explicitely told, but will we >>> writeback when we munmap? > munmap() and fsync() or msync() will flush it to disk; there is no reason > munmap() should unless perhaps the file was opened O_SYNC. Wait a minute. Shouldn't a file opened O_SYNC flush the writes as they happen, removing the requirement for any explicit syncing? If it doesn't there are some very broken apps around. Chris -- Chris Friesen | MailStop: 043/33/F10 Nortel Networks | work: (613) 765-0557 3500 Carling Avenue | fax: (613) 765-2986 Nepean, ON K2H 8E9 Canada | email: cfriesen@nortelnetworks.com