From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from 87-104-106-3-dynamic-customer.profibernet.dk ([87.104.106.3]:46570 "EHLO kernel.dk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753773Ab1ICDJf (ORCPT ); Fri, 2 Sep 2011 23:09:35 -0400 Message-ID: <4E619A66.4040605@kernel.dk> Date: Fri, 02 Sep 2011 21:09:26 -0600 From: Jens Axboe MIME-Version: 1.0 Subject: Re: Bad performance when reads and writes on same LUN References: <116197A0179A3D4A95B135E5F0341FC11041B4D8@SACMVEXC2-PRD.hq.netapp.com> In-Reply-To: <116197A0179A3D4A95B135E5F0341FC11041B4D8@SACMVEXC2-PRD.hq.netapp.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Sender: fio-owner@vger.kernel.org List-Id: fio@vger.kernel.org To: "Neto, Antonio Jose Rodrigues" Cc: zhu.yanhai@gmail.com, "Rettl, Matthias" , fio@vger.kernel.org On 2011-09-02 21:06, Neto, Antonio Jose Rodrigues wrote: > The question that I have is: > > "Buffered aio will fall back to sync io, and it's known that mixing" > > Why did buffered aio will fall back to sync io? Please don't top post, reply beneat the original text. Buffered aio will degenerate to normal sync IO, because the kernel does not support async buffered io. -- Jens Axboe