From owner-freebsd-fs@freebsd.org Sat Jan 21 09:28:06 2017 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 E8C0ECB9785 for ; Sat, 21 Jan 2017 09:28:06 +0000 (UTC) (envelope-from cipher_nl@hotmail.com) Received: from mailman.ysv.freebsd.org (mailman.ysv.freebsd.org [IPv6:2001:1900:2254:206a::50:5]) by mx1.freebsd.org (Postfix) with ESMTP id B7C351566 for ; Sat, 21 Jan 2017 09:28:06 +0000 (UTC) (envelope-from cipher_nl@hotmail.com) Received: by mailman.ysv.freebsd.org (Postfix) id B718CCB9784; Sat, 21 Jan 2017 09:28:06 +0000 (UTC) Delivered-To: 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 B6B84CB9783 for ; Sat, 21 Jan 2017 09:28:06 +0000 (UTC) (envelope-from cipher_nl@hotmail.com) Received: from BAY004-OMC3S13.hotmail.com (bay004-omc3s13.hotmail.com [65.54.190.151]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-SHA384 (256/256 bits)) (Client CN "*.outlook.com", Issuer "Microsoft IT SSL SHA2" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 8A7F41564 for ; Sat, 21 Jan 2017 09:28:06 +0000 (UTC) (envelope-from cipher_nl@hotmail.com) Received: from EUR03-AM5-obe.outbound.protection.outlook.com ([65.54.190.188]) by BAY004-OMC3S13.hotmail.com over TLS secured channel with Microsoft SMTPSVC(7.5.7601.23008); Sat, 21 Jan 2017 01:27:00 -0800 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=hotmail.com; s=selector1; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version; bh=tb/g5UcbO4rU9FETwv1/cEJNMIKp4S1mHRUC+8Khqhc=; b=khDFsl0eM8FnZjNboI5OYcXHfjShd5z/U4g1rCXOe2SDMJDJsWdHl4+i8sFt+t3Ec+5c0B9niZLAiP8RzEIvxhDNOzGeOmxzDrZCk14K6X+BXJcFeM6VTqqICoIGYQuqPU+m02Raj1y/Kdrs2gruDeyQkN/N2LJmKNvZAfrVzO+ltl9QEyv6egP1Ymbr9GPYCuihMdfb/dvXPyokFeq0uwMITElIdN7jpOB+a4/JeZnFUgXqfsqaKOUOIINtY1hJKGhYlS0Ne88HBqyBRYbonNxwLH89hxb+gec0rx/KeNXpgOt7DTVYWn1m18tZ7PzrI4Rkv+If7A6XG5OjiDgLsA== Received: from DB5EUR03FT052.eop-EUR03.prod.protection.outlook.com (10.152.20.55) by DB5EUR03HT180.eop-EUR03.prod.protection.outlook.com (10.152.21.89) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA384_P384) id 15.1.803.8; Sat, 21 Jan 2017 09:26:58 +0000 Received: from DB6PR0801MB1622.eurprd08.prod.outlook.com (10.152.20.53) by DB5EUR03FT052.mail.protection.outlook.com (10.152.21.82) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA384_P384) id 15.1.803.8 via Frontend Transport; Sat, 21 Jan 2017 09:26:57 +0000 Received: from DB6PR0801MB1622.eurprd08.prod.outlook.com ([10.169.226.10]) by DB6PR0801MB1622.eurprd08.prod.outlook.com ([10.169.226.10]) with mapi id 15.01.0860.018; Sat, 21 Jan 2017 09:26:58 +0000 From: "D. E" To: Alex Povolotsky , "fs@freebsd.org" Subject: Re: Poor ZFS performance Thread-Topic: Poor ZFS performance Thread-Index: AQHSc8N15Axkuc7NzUGbaTLlBQOz/KFCqWER Date: Sat, 21 Jan 2017 09:26:58 +0000 Message-ID: References: <083391de-d153-e0f6-c453-63d95d3e1f55@webmail.sub.ru> In-Reply-To: <083391de-d153-e0f6-c453-63d95d3e1f55@webmail.sub.ru> Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: authentication-results: webmail.sub.ru; dkim=none (message not signed) header.d=none; webmail.sub.ru; dmarc=none action=none header.from=hotmail.com; x-incomingtopheadermarker: OriginalChecksum:E2C86382044B6F8F37172BDF5B3A4780B7A9A3198F20A249012C0E6E9E39F66C; UpperCasedChecksum:0443A63C591237F133EF18E03ECF580916FF17A49A5E7780AEB834884EAA9880; SizeAsReceived:7619; Count:39 x-ms-exchange-messagesentrepresentingtype: 1 x-tmn: [z4/hnPJkhewMCYWoU1sxGI4RZaludDb7] x-incomingheadercount: 39 x-eopattributedmessage: 0 x-microsoft-exchange-diagnostics: 1; DB5EUR03HT180; 7:Mn6JE0TYj+zyGXC51qNiDuQ22lSJX47s4TvBueHMtNa1IP/8vj+qUk1f3gj3qI+TfbunPk8WZ+radXmgUQ4Hk7YKZ0Y2n6y3P2TYm5rj2IGcimv4c3L2iZKLZQKkforltQmwxpnBQ5MLMrX1169zx6ygN+HnLEL4/698lItcf3jZftPCSeDTSCtV/TR+o0etpSDbh6RWR2Ao0yD2Cf28snRsC9p2idcpJPOlGrNpAjZB+oYHZufOdaJtVjLdb0+h1hb4Wg80PPtqrnCc4TXCeKbLhimxco4d1Y9dzPqjJ9yPxmQ/pNoaBNAvU8Je3Ab7eheanfAxgEqkl2ioU0yMGfIJphAE/QXwH+TIQrRVqgUSlTgSGt5Cx35rmB9zNHo+SFjqY3BIwl3wG9t1gSUtRegRUCw3W3NktnaQhqzunA9HxdKWrhy8AXdi0APpQz8yI/Lmo9icQQFhGTVx9VFTIQ== x-forefront-antispam-report: EFV:NLI; SFV:NSPM; SFS:(10019020)(98900005); DIR:OUT; SFP:1102; SCL:1; SRVR:DB5EUR03HT180; H:DB6PR0801MB1622.eurprd08.prod.outlook.com; FPR:; SPF:None; LANG:en; x-ms-office365-filtering-correlation-id: 0139538b-ae7c-47b9-5d2e-08d441dfa602 x-microsoft-antispam: UriScan:; BCL:0; PCL:0; RULEID:(22001)(1601124038)(5061506344)(1603103113)(1601125047)(1701031023); SRVR:DB5EUR03HT180; x-exchange-antispam-report-cfa-test: BCL:0; PCL:0; RULEID:(444111334)(444112120)(432015012)(82015046); SRVR:DB5EUR03HT180; BCL:0; PCL:0; RULEID:; SRVR:DB5EUR03HT180; x-forefront-prvs: 01949FE337 spamdiagnosticoutput: 1:99 spamdiagnosticmetadata: NSPM Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 X-OriginatorOrg: hotmail.com X-MS-Exchange-CrossTenant-originalarrivaltime: 21 Jan 2017 09:26:58.2786 (UTC) X-MS-Exchange-CrossTenant-fromentityheader: Internet X-MS-Exchange-CrossTenant-id: 84df9e7f-e9f6-40af-b435-aaaaaaaaaaaa X-MS-Exchange-Transport-CrossTenantHeadersStamped: DB5EUR03HT180 X-OriginalArrivalTime: 21 Jan 2017 09:27:00.0794 (UTC) FILETIME=[84ECF1A0:01D273C8] 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: Sat, 21 Jan 2017 09:28:07 -0000 >I'm writing lots of (tens of millions) relatively small files, hashing=20 >them out in three-level directory, 100 entries per level. >Speed is quite unsatisfying, about 2 millions files per day writing in=20 >20 processes, that is, about one file per second for process. But that is to be expected, isn't it? You have chosen hardware which is *EX= TREMELY* slow for non-contiguous write access. The Seagate Archive HDD is a= n SMR harddrive suitable for archive storage - not a generic PMR harddrive.= So the Seagate Archive HDD is suitable for makings backups and writing hug= e files like 1TB images which you write from A to Z. SMR drives are notorio= usly slow when it comes to non-contiguous writes, such as writing small fil= es. You can read warnings about SMR and the Seagate Archive HDD in particular e= verywhere on the web. Have you missed them? Slightly exaggerated: your SMR-drive is more like a tapestreamer than a rea= l harddrive. It should be used to store enormous files and used for 'cold s= torage'. Read more about the Seagate Archive HDD on its website: http://www.seagate.= com/enterprise-storage/hard-disk-drives/archive-hdd/ To be honest, it is the worst harddrive one can buy today for the purpose o= f regular storage (hot storage). For cold storage, such as backups like tap= estreamers do the drive is decent, but not good by any means. 1,33TB per pl= atter is disappointing for SMR considering the massive downsides. And some = PMR drives are even cheaper per gigabyte than this SMR drive. So i strongly= recommend against SMR at this time. Regards, CiPHER=