From: Kazuya Mio Subject: Re: bio splits unnecessarily due to BH_Boundary in ext3 direct I/O Date: Tue, 19 Mar 2013 17:36:17 +0900 Message-ID: <51482381.7010508@sx.jp.nec.com> References: <51385177.9030904@sx.jp.nec.com> <20130307104854.GB6723@quack.suse.cz> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: akpm@linux-foundation.org, adilger.kernel@dilger.ca, linux-ext4@vger.kernel.org To: Jan Kara Return-path: Received: from TYO200.gate.nec.co.jp ([210.143.35.50]:47316 "EHLO tyo200.gate.nec.co.jp" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756083Ab3CSIpP (ORCPT ); Tue, 19 Mar 2013 04:45:15 -0400 Received: from tyo202.gate.nec.co.jp ([10.7.69.202]) by tyo200.gate.nec.co.jp (8.13.8/8.13.4) with ESMTP id r2J8jEhC029597 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO) for ; Tue, 19 Mar 2013 17:45:14 +0900 (JST) In-Reply-To: <20130307104854.GB6723@quack.suse.cz> Sender: linux-ext4-owner@vger.kernel.org List-ID: 2013/03/07 19:48, Jan Kara wrote: > Then we properly mark bio should be submitted only if we are mapping last > part of the mapped extent from the filesystem. Can you give this change a > try (full patch with changelog attached)? Sorry for the late response. After applying your patch, the problem I reported was fixed. One matter for concern is that submit_bio() is called twice per one buffer_head. Because submit_page_section() calls dio_bio_submit() before adding the old page (sdio->cur_page) and the current page to struct dio_submit. Does it work as required? Regards, Kazuya Mio