From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S264008AbTDJIvj (for ); Thu, 10 Apr 2003 04:51:39 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S264009AbTDJIvj (for ); Thu, 10 Apr 2003 04:51:39 -0400 Received: from dial-ctb05177.webone.com.au ([210.9.245.177]:11013 "EHLO chimp.local.net") by vger.kernel.org with ESMTP id S264008AbTDJIvi (for ); Thu, 10 Apr 2003 04:51:38 -0400 Message-ID: <3E953317.1090406@cyberone.com.au> Date: Thu, 10 Apr 2003 19:02:15 +1000 From: Nick Piggin User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.3) Gecko/20030327 Debian/1.3-4 X-Accept-Language: en MIME-Version: 1.0 To: Keith Ansell CC: Andrew Morton , Andre Hedrick , linux-kernel@vger.kernel.org, axboe@suse.de Subject: Re: bdflush flushing memory mapped pages. References: <007601c2fecd$12209070$230110ac@kaws> <20030409022726.1ec93a0f.akpm@digeo.com> <01bc01c2ff9d$0dc1aca0$230110ac@kaws> In-Reply-To: <01bc01c2ff9d$0dc1aca0$230110ac@kaws> 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 Keith Ansell wrote: >Thank you for your prompt replies. > >I realise that Linux conforms to the letter of the specification, but maybe >not the spirit of the it. > >I am porting a Database solution to Linux from Unix SVR4, Sco OpenServer and >AIX, where all write required memory mapped files are flushed to disk with >the system flusher, my users have large systems (some in excess of 600 >concurrent connections) flushing memory mapped files is a big part of are >systems performance. This ensures that in the event of a catastrophic >system failure the customers vitual business data has been written to disk . > As Andrew mentioned, msync would do what you want. It seems to me though, that your database solution wants a stronger guarantee about the safety of the data than asynchronous writes will provide anyway.