Return-Path: linux-nfs-owner@vger.kernel.org Received: from acsinet15.oracle.com ([141.146.126.227]:53336 "EHLO acsinet15.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753373Ab2AaCKn (ORCPT ); Mon, 30 Jan 2012 21:10:43 -0500 To: Bernd Schubert Cc: "Martin K. Petersen" , Chuck Lever , lsf-pc@lists.linux-foundation.org, linux-fsdevel , Linux NFS Mailing List , linux-scsi@vger.kernel.org, Sven Breuner Subject: Re: [LSF/MM TOPIC] end-to-end data and metadata corruption detection From: "Martin K. Petersen" References: <38C050B3-2AAD-4767-9A25-02C33627E427@oracle.com> <4F2147BA.6030607@itwm.fraunhofer.de> <4F217F0C.6030105@itwm.fraunhofer.de> Date: Mon, 30 Jan 2012 21:10:31 -0500 In-Reply-To: <4F217F0C.6030105@itwm.fraunhofer.de> (Bernd Schubert's message of "Thu, 26 Jan 2012 17:27:56 +0100") Message-ID: MIME-Version: 1.0 Content-Type: text/plain Sender: linux-nfs-owner@vger.kernel.org List-ID: >>>>> "Bernd" == Bernd Schubert writes: Bernd> Hmm, direct IO would mean we could not use the page cache. As we Bernd> are using it, that would not really suit us. libaio then might be Bernd> another option then. Bernd> What kind of help do you exactly need? As far as libaio is concerned I had a PoC working a few years ago. I'll be happy to revive it if people are actually interested. So a real world use case would be a great help... But James is right that buffered I/O is much more challenging than direct I/O. And all the use cases we have had have involved databases and business apps that were doing direct I/O anyway. -- Martin K. Petersen Oracle Linux Engineering