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 72F99EB64DD for ; Tue, 1 Aug 2023 08:36:03 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230507AbjHAIgC (ORCPT ); Tue, 1 Aug 2023 04:36:02 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46250 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229455AbjHAIgA (ORCPT ); Tue, 1 Aug 2023 04:36:00 -0400 Received: from verein.lst.de (verein.lst.de [213.95.11.211]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 0C9761B6 for ; Tue, 1 Aug 2023 01:36:00 -0700 (PDT) Received: by verein.lst.de (Postfix, from userid 2407) id B901768AFE; Tue, 1 Aug 2023 10:35:56 +0200 (CEST) Date: Tue, 1 Aug 2023 10:35:56 +0200 From: Christoph Hellwig To: Wang Yugui Cc: Christoph Hellwig , linux-btrfs@vger.kernel.org Subject: Re: btrfs write-bandwidth performance regression of 6.5-rc4/rc3 Message-ID: <20230801083556.GA24287@lst.de> References: <20230731152223.4EFB.409509F4@e16-tech.com> <20230801102253.1AF4.409509F4@e16-tech.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20230801102253.1AF4.409509F4@e16-tech.com> User-Agent: Mutt/1.5.17 (2007-11-01) Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org 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?