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 X-Spam-Level: X-Spam-Status: No, score=-3.5 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id BC7FBC433E1 for ; Wed, 26 Aug 2020 18:35:54 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 6D8692083B for ; Wed, 26 Aug 2020 18:35:54 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=igalia.com header.i=@igalia.com header.b="bmi0CLc7" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 6D8692083B Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=igalia.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:57876 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1kB0H3-0004X6-Ld for qemu-devel@archiver.kernel.org; Wed, 26 Aug 2020 14:35:53 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:57250) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1kB0Fu-0002yV-V1; Wed, 26 Aug 2020 14:34:42 -0400 Received: from fanzine.igalia.com ([178.60.130.6]:54343) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.90_1) (envelope-from ) id 1kB0Fs-0008PK-A5; Wed, 26 Aug 2020 14:34:42 -0400 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=igalia.com; s=20170329; h=Content-Type:MIME-Version:Message-ID:Date:References:In-Reply-To:Subject:Cc:To:From; bh=/hZsxkMu//hdGcZkF5Nm74Qa9GNadrEHHn2DxAUVZIU=; b=bmi0CLc7gmloG25iu/MacY9fKilBV5Nr4ohkoFSXdpWnKCDDLjx/QC6KwXFp6S31dCWTw0876dfiJC+JWHR4W/YpTiGyOlmGQ7QSlVgUjrE5nwD4ycQLQWtmxOeDqH2QFagkrhbZCepO44yHFL+fTuDxAHqJ4jDW2ua1HJrYNOU8K1WMcIJ2KY3OCVqv82Yd/d46cFqMy+/qlKoW5oCqPCOqEf/FDpAaBAsB3OlWjkUGo9EUyIpXDr3mWGktuk4naoyjXGd5P+dnwQk8my8mFv9L4mWreppAPHn9PX/IVtPjLyL7GEUvonKeiK+QssAeFZ8lNAlouthQJg5uL0rVxQ==; Received: from maestria.local.igalia.com ([192.168.10.14] helo=mail.igalia.com) by fanzine.igalia.com with esmtps (Cipher TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim) id 1kB0Fk-0007fI-GJ; Wed, 26 Aug 2020 20:34:32 +0200 Received: from berto by mail.igalia.com with local (Exim) id 1kB0Fk-00026U-6m; Wed, 26 Aug 2020 20:34:32 +0200 From: Alberto Garcia To: Brian Foster Subject: Re: [PATCH 0/1] qcow2: Skip copy-on-write when allocating a zero cluster In-Reply-To: <20200825194724.GA338144@bfoster> References: <20200819175300.GA141399@bfoster> <20200820215811.GC7941@dread.disaster.area> <20200821110506.GB212879@bfoster> <20200821170232.GA220086@bfoster> <20200825165415.GB321765@bfoster> <20200825194724.GA338144@bfoster> User-Agent: Notmuch/0.18.2 (http://notmuchmail.org) Emacs/24.4.1 (i586-pc-linux-gnu) Date: Wed, 26 Aug 2020 20:34:32 +0200 Message-ID: MIME-Version: 1.0 Content-Type: text/plain Received-SPF: pass client-ip=178.60.130.6; envelope-from=berto@igalia.com; helo=fanzine.igalia.com X-detected-operating-system: by eggs.gnu.org: First seen = 2020/08/26 14:00:31 X-ACL-Warn: Detected OS = Linux 2.2.x-3.x (no timestamps) [generic] [fuzzy] X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Kevin Wolf , Vladimir Sementsov-Ogievskiy , qemu-block@nongnu.org, Dave Chinner , qemu-devel@nongnu.org, Max Reitz , linux-xfs@vger.kernel.org Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On Tue 25 Aug 2020 09:47:24 PM CEST, Brian Foster wrote: > My fio fallocates the entire file by default with this command. Is that > the intent of this particular test? I added --fallocate=none to my test > runs to incorporate the allocation cost in the I/Os. That wasn't intentional, you're right, it should use --fallocate=none (I don't see a big difference in my test anyway). >> The Linux version is 4.19.132-1 from Debian. > > Thanks. I don't have LUKS in the mix on my box, but I was running on a > more recent kernel (Fedora 5.7.15-100). I threw v4.19 on the box and > saw a bit more of a delta between XFS (~14k iops) and ext4 (~24k). The > same test shows ~17k iops for XFS and ~19k iops for ext4 on v5.7. If I > increase the size of the LVM volume from 126G to >1TB, ext4 runs at > roughly the same rate and XFS closes the gap to around ~19k iops as > well. I'm not sure what might have changed since v4.19, but care to > see if this is still an issue on a more recent kernel? Ok, I gave 5.7.10-1 a try but I still get similar numbers. Perhaps with a larger filesystem there would be a difference? I don't know. Berto