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 3B3D1C001E0 for ; Tue, 1 Aug 2023 09:34:51 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233096AbjHAJes (ORCPT ); Tue, 1 Aug 2023 05:34:48 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35214 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233090AbjHAJeY (ORCPT ); Tue, 1 Aug 2023 05:34:24 -0400 Received: from out28-68.mail.aliyun.com (out28-68.mail.aliyun.com [115.124.28.68]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 0F6E45257 for ; Tue, 1 Aug 2023 02:32:18 -0700 (PDT) X-Alimail-AntiSpam: AC=CONTINUE;BC=0.09385116|-1;CH=green;DM=|CONTINUE|false|;DS=CONTINUE|ham_system_inform|0.0260082-0.000822041-0.97317;FP=0|0|0|0|0|-1|-1|-1;HT=ay29a033018047202;MF=wangyugui@e16-tech.com;NM=1;PH=DS;RN=2;RT=2;SR=0;TI=SMTPD_---.U5re6TG_1690882328; Received: from 192.168.2.112(mailfrom:wangyugui@e16-tech.com fp:SMTPD_---.U5re6TG_1690882328) by smtp.aliyun-inc.com; Tue, 01 Aug 2023 17:32:12 +0800 Date: Tue, 01 Aug 2023 17:32:13 +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: <20230801090316.GA25781@lst.de> References: <20230801165652.760D.409509F4@e16-tech.com> <20230801090316.GA25781@lst.de> Message-Id: <20230801173208.4F08.409509F4@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 04:56:58PM +0800, Wang Yugui wrote: > > > 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. > > Is this in a VM and not passing through cpu flags? What does dmesg > say when mounting? Norally it should say something like: > > [ 23.461448] BTRFS info (device vdb): using crc32c (crc32c-intel) checksum algorithm This is NOT VM. dmesg output: [ 250.596544] raid6: skipped pq benchmark and selected sse2x4 [ 250.602836] raid6: using ssse3x2 recovery algorithm [ 250.612812] xor: automatically using best checksumming function avx [ 250.895573] Btrfs loaded, assert=on, zoned=yes, fsverity=no [ 250.905249] BTRFS: device fsid f5ebfdd6-6bf6-4c2b-b47b-79517bc00c8f devid 3 transid 6 /dev/nvme3n1 scanned by systemd-udevd (1726) [ 250.922155] BTRFS: device fsid f5ebfdd6-6bf6-4c2b-b47b-79517bc00c8f devid 4 transid 6 /dev/nvme0n1 scanned by systemd-udevd (1729) [ 250.935965] BTRFS: device fsid f5ebfdd6-6bf6-4c2b-b47b-79517bc00c8f devid 1 transid 6 /dev/nvme1n1 scanned by systemd-udevd (1724) [ 250.968268] BTRFS: device fsid f5ebfdd6-6bf6-4c2b-b47b-79517bc00c8f devid 2 transid 6 /dev/nvme2n1 scanned by systemd-udevd (1723) [ 251.070139] BTRFS info (device nvme1n1): using crc32c (crc32c-intel) checksum algorithm [ 251.079164] BTRFS info (device nvme1n1): using free space tree [ 251.089871] BTRFS info (device nvme1n1): enabling ssd optimizations [ 251.096921] BTRFS info (device nvme1n1): auto enabling async discard [ 251.104417] BTRFS info (device nvme1n1): checking UUID tree Best Regards Wang Yugui (wangyugui@e16-tech.com) 2023/08/01