From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from [95.166.99.235] ([95.166.99.235]:46250 "EHLO kernel.dk" rhost-flags-FAIL-FAIL-OK-OK) by vger.kernel.org with ESMTP id S1750826AbZKDHfV (ORCPT ); Wed, 4 Nov 2009 02:35:21 -0500 Date: Wed, 4 Nov 2009 08:35:26 +0100 From: Jens Axboe Subject: Re: Add extra_buff_count flag Message-ID: <20091104073525.GQ8742@kernel.dk> References: <66dfd3fe0911031633s5bef0621g99b4164c2dd174d9@mail.gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <66dfd3fe0911031633s5bef0621g99b4164c2dd174d9@mail.gmail.com> Sender: fio-owner@vger.kernel.org List-Id: fio@vger.kernel.org To: Radha Ramachandran Cc: fio@vger.kernel.org On Tue, Nov 03 2009, Radha Ramachandran wrote: > Hi, > I was trying to use the async_verify option. Looks like if we use this > option for synchronous I/O, then it really doesnt do anything as after > every I/O is completed, we still need the asynchronous verify thread > to complete the verification and release the io_u so the main thread > can allocate this io_u for the next I/O. So to remove this bottle neck > I added a new option extra_buff_count. This takes an integer and the > code will allocate that many more extra io_us. This way when the main > thread has completed the I/O it will have extra io_u and buffers to > issue more I/Os while the asynchronous verify threads do their job. > This can be used with both synchronous and libaio contexts. Does iodepth=x not work for that? If not, I suggest we fix that instead of adding a new parameter for it. -- Jens Axboe