From owner-freebsd-fs@freebsd.org Tue Dec 6 20:26:26 2016 Return-Path: Delivered-To: freebsd-fs@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id 10656C6AA5D for ; Tue, 6 Dec 2016 20:26:26 +0000 (UTC) (envelope-from mavbsd@gmail.com) Received: from mail-wm0-x243.google.com (mail-wm0-x243.google.com [IPv6:2a00:1450:400c:c09::243]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (Client CN "smtp.gmail.com", Issuer "Google Internet Authority G2" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id B07AF1001; Tue, 6 Dec 2016 20:26:25 +0000 (UTC) (envelope-from mavbsd@gmail.com) Received: by mail-wm0-x243.google.com with SMTP id u144so23699933wmu.0; Tue, 06 Dec 2016 12:26:25 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=sender:to:cc:from:subject:message-id:date:user-agent:mime-version :content-transfer-encoding; bh=rbgkUp1g3sVbNFFPCgueXPoCKV0sDZWuBHErZWLXGtE=; b=Hc124s1Tu++uWs3AoA8H8KU2XXLGtjIoIhRbbylQrne6rBw8Bx7WDy5LsW5f+rQuWa aPytFyWp1h/iCCeV2qKg6V/bxdcTs2Hik43wLSLzN8LN11cEtRoF65hw+29BGCoX0azD oXeXUpqwIhfRGwfl61bWGI82MmfyAA1oZW/o1BCmGy9Pe+5TPQBsi59SjNE9M4Hd6152 +z8AOGkgGXLVNXBsobKKLgkIN9vyP18C8GYPiPhhA1JCAQKBooRCvJgEPGfivtFjCDKS K5cWuZquZ+lSMcF5NlT3qcgUJutiOARx1dOGGzrjPH8NMf2VQKWVBmUFVz0rcRiP8bYo 4CQg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:sender:to:cc:from:subject:message-id:date :user-agent:mime-version:content-transfer-encoding; bh=rbgkUp1g3sVbNFFPCgueXPoCKV0sDZWuBHErZWLXGtE=; b=BlBUMaI/V7PJJSFboud4S9VzwDsf0buHVfKyFfAGWl/0D6Rzc//YzYf6FrtedtTqj8 0xVrqXRjHO0oSa8X4ql76sOlkQvhm0GOCQg4jDDscS0LRlf/DZ5wKGsQoo9n4y4hA4xu Ux4FJV0evisbQ9RWEeTU9U7QXl9bYFUNfo/w1FzP0ozLyQmlbxsP5GBar+diIRo2V27s n0k66b6LYKx36fOr30auFAnfqNPdmXP1mlbAbl59Ez9czWFlZmSOJQrQgXVZo36UuoO4 81JGjClcQpCn5BEKd2T4m9Y3yMyzg8mPvm1OWZLtXPfJEKqQ31VOqQ4a5Dhzm+LMlGzZ KxMA== X-Gm-Message-State: AKaTC00tSbToRHyB0os33D5CuoBNbwqx84c2HN8VBjNwa4glxmqrtoIaHniJsyxhJ3sdHQ== X-Received: by 10.46.76.18 with SMTP id z18mr30092861lja.38.1481055983079; Tue, 06 Dec 2016 12:26:23 -0800 (PST) Received: from spectre.mavhome.dp.ua ([134.249.139.101]) by smtp.gmail.com with ESMTPSA id y10sm4129645lja.45.2016.12.06.12.26.21 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Tue, 06 Dec 2016 12:26:22 -0800 (PST) Sender: Alexander Motin To: freebsd-fs@FreeBSD.org Cc: Alex Tutubalin , Andriy Gapon From: Alexander Motin Subject: Re: 11-STABLE vs 11.0-RELENG test Message-ID: <8b4ba98d-03d3-f671-33b2-ed12d3b4fb7c@FreeBSD.org> Date: Tue, 6 Dec 2016 22:26:21 +0200 User-Agent: Mozilla/5.0 (X11; FreeBSD amd64; rv:45.0) Gecko/20100101 Thunderbird/45.4.0 MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit X-BeenThere: freebsd-fs@freebsd.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: Filesystems List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 06 Dec 2016 20:26:26 -0000 On 06/12/2016 18:17, Alex Tutubalin wrote: > Followup, same box as in 1st message, but with different HBA and 5 HDD: > > Summary: > 1) read speed depends on 'on-disk' data, not by code used while read. > 2) FreeBSD 11.0-releng (svn up today) creates 'fast' big files (420+ Mb/s read > speed) > 3) FreeBSD 11-STABLE creates 'slow' big files. (~200 Mb/s) > 4) zfs send slow-dataset | zfs recv (under 11.0-releng) creates > 'intermediate' files (320Mb/s) > 5) file copy slow-file ... (under 11.0-releng) creates fast copy (400+Mb/s) > > So, ZFS write code in 11-STABLE looks broken. I've reproduced this issue with quick test on my lab system configured with 12-disk RAIDZ2 pool. I've measured write and read back (with and without prefetch) speeds for pool recreated on different FreeBSD head revisions: r309625 r305456 r305330 r305322 write 702 701 1115 1120 read w/ pref 232 228 518 512 read w/o pref 128 126 242 240 I suspect we could obtain the problem here: r305331 | mav | 2016-09-03 13:04:37 +0300 (сб, 03 сент. 2016) | 45 lines MFV r304155: 7090 zfs should improve allocation order and throttle allocations I'll take closer look on that change tomorrow. -- Alexander Motin