From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id F2C06EB64DD for ; Tue, 1 Aug 2023 08:57:25 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230011AbjHAI5Z (ORCPT ); Tue, 1 Aug 2023 04:57:25 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56970 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229904AbjHAI5X (ORCPT ); Tue, 1 Aug 2023 04:57:23 -0400 Received: from out28-65.mail.aliyun.com (out28-65.mail.aliyun.com [115.124.28.65]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D66F82108 for ; Tue, 1 Aug 2023 01:57:04 -0700 (PDT) X-Alimail-AntiSpam: AC=CONTINUE;BC=0.2156001|-1;CH=green;DM=|CONTINUE|false|;DS=CONTINUE|ham_enroll_verification|0.0114828-0.000765547-0.987752;FP=0|0|0|0|0|-1|-1|-1;HT=ay29a033018047207;MF=wangyugui@e16-tech.com;NM=1;PH=DS;RN=2;RT=2;SR=0;TI=SMTPD_---.U5om-Ft_1690880212; Received: from 192.168.2.112(mailfrom:wangyugui@e16-tech.com fp:SMTPD_---.U5om-Ft_1690880212) by smtp.aliyun-inc.com; Tue, 01 Aug 2023 16:56:57 +0800 Date: Tue, 01 Aug 2023 16:56:58 +0800 From: Wang Yugui To: Christoph Hellwig Subject: Re: btrfs write-bandwidth performance regression of 6.5-rc4/rc3 Cc: linux-btrfs@vger.kernel.org In-Reply-To: <20230801083556.GA24287@lst.de> References: <20230801102253.1AF4.409509F4@e16-tech.com> <20230801083556.GA24287@lst.de> Message-Id: <20230801165652.760D.409509F4@e16-tech.com> MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit X-Mailer: Becky! ver. 2.81.04 [en] Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org Hi, > On Tue, Aug 01, 2023 at 10:22:58AM +0800, Wang Yugui wrote: > > 'git bisect' show that this patch is the root cause of performance > > regression. > > > > e917ff56c8e7 :Christoph Hellwig: btrfs: determine synchronous writers from bio > > or writeback control > > Odd. What CPU are you using to test? It seems like it doesn't set > BTRFS_FS_CSUM_IMPL_FAST as that is the only way to even hit a potential > difference. Or are you using a non-standard checksum type? The CPU is E5 2680 v2. and I used the default checksum type of mkfs.btrfs v6.1 dd(conv=fsync)(single threads) works well. fio(multiple jobs) does NO work well. so maybe some problem of lock? Best Regards Wang Yugui (wangyugui@e16-tech.com) 2023/08/01