From owner-freebsd-fs@freebsd.org Sat Jan 21 09:53:28 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 46D74CBA107 for ; Sat, 21 Jan 2017 09:53:28 +0000 (UTC) (envelope-from ben.rubson@gmail.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 23B0710CC for ; Sat, 21 Jan 2017 09:53:28 +0000 (UTC) (envelope-from ben.rubson@gmail.com) Received: by mailman.ysv.freebsd.org (Postfix) id 2306ECBA106; Sat, 21 Jan 2017 09:53:28 +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 22A9CCBA105 for ; Sat, 21 Jan 2017 09:53:28 +0000 (UTC) (envelope-from ben.rubson@gmail.com) Received: from mail-wm0-x22a.google.com (mail-wm0-x22a.google.com [IPv6:2a00:1450:400c:c09::22a]) (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 AAE9D10CB for ; Sat, 21 Jan 2017 09:53:27 +0000 (UTC) (envelope-from ben.rubson@gmail.com) Received: by mail-wm0-x22a.google.com with SMTP id r126so68797054wmr.0 for ; Sat, 21 Jan 2017 01:53:27 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:subject:from:in-reply-to:date :content-transfer-encoding:message-id:references:to; bh=DC5mMgkqKlRNhsi4GAnIARK08X0XH/r5DXGRGInv63w=; b=qSK8AyYip31gk/zz/isOCkyrLAtL1v67X86xAVcERqI0xXUz5e3Dnj0Knk15h6VmRr BNsMFKK8Fedc9wTRwusFohzQSkPwh341963uFxRyOE+b0vzbdEwTbgBwUWBuIO6OdtDa WCTg+Vtn5XzdodxmE9OWM42y3qXG5vUkXrkj8XhFAUEWX52iU6ORbYbqVu/3bQ/cx2EA r0Y6MYapA0LFWQUFgv0kMWOZx5VtQvJek5jQW0/m5ElaHOGe6sGziy89K4dwEhGT3/+/ M7skTAftJggwHPyvKQI3ifu9FkhyP5W4WyZToSHz0Mouv02xCqkDq4r4L9CFdFXS01Ap JIVQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:subject:from:in-reply-to:date :content-transfer-encoding:message-id:references:to; bh=DC5mMgkqKlRNhsi4GAnIARK08X0XH/r5DXGRGInv63w=; b=cdBI9oC05ar7/X6xytXMAElYeQg4mesv7pTo8uewcDH8hrHsDAG8KvHXZ59WXIDq6z lwdC1GaeXVRgV6ez++AX5Qf54PVF7a6D1AZXA/TVm2OQX0HsRkzqmR0tY4XciReDsXbU jWUoHFV0lgqWegqphqL5UyriKZeIwdRmy3fMbRFz21FfYyrdPBhRy/pvjAIlVOu0nolK InN9G163Zbhl1vr/VuXusiL/ZPJskedB1gPPtxbyoClnbjKCYztXyvgEvkHx6bNUNVwy jfa+FkKgCTCK5+WsoAly4QVaGyltWx15dorW0GEPosbLqQf5m0oCBs5aYczwQpJMofJz 9JgQ== X-Gm-Message-State: AIkVDXLC1cOwIg0ZlVDtHT8pFbAVhQjP0kv2mp1ckYIOfyBr4cyTIjmprSP/2vZaw2Njlg== X-Received: by 10.28.129.147 with SMTP id c141mr7151307wmd.12.1484992405189; Sat, 21 Jan 2017 01:53:25 -0800 (PST) Received: from ben.home (LFbn-1-7159-4.w90-116.abo.wanadoo.fr. [90.116.90.4]) by smtp.gmail.com with ESMTPSA id s26sm3668987wra.26.2017.01.21.01.53.24 for (version=TLS1 cipher=ECDHE-RSA-AES128-SHA bits=128/128); Sat, 21 Jan 2017 01:53:24 -0800 (PST) Content-Type: text/plain; charset=us-ascii Mime-Version: 1.0 (Mac OS X Mail 9.3 \(3124\)) Subject: Re: Poor ZFS performance From: Ben RUBSON In-Reply-To: Date: Sat, 21 Jan 2017 10:53:23 +0100 Content-Transfer-Encoding: quoted-printable Message-Id: <963575CE-F74A-456A-AB33-3C5F6828ED17@gmail.com> References: <083391de-d153-e0f6-c453-63d95d3e1f55@webmail.sub.ru> To: "fs@freebsd.org" X-Mailer: Apple Mail (2.3124) 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 09:53:28 -0000 Hi, What about a primary pool made of SSD ? They should fit your workload much better than platter disks. Ben > On 21 Jan 2017, at 10:47, Alex Povolotsky = wrote: >=20 > So fetching data to, say, ST2000NM0055-1V4104, and than zfs send | zfs = receive to Archive HDD will do the trick? >=20 > Seems like the answer is "yes", I've got 3-4 times speed improvement. = In an hour, I'll try partial transfer. >=20 > What 8 Tb disk would you recommend for raidz? >=20 > On 21.01.2017 12:26, D. E wrote: >>> I'm writing lots of (tens of millions) relatively small files, = hashing >>> them out in three-level directory, 100 entries per level. >>=20 >>> Speed is quite unsatisfying, about 2 millions files per day writing = in >>> 20 processes, that is, about one file per second for process. >>=20 >> But that is to be expected, isn't it? You have chosen hardware which = is *EXTREMELY* slow for non-contiguous write access. The Seagate Archive = HDD is an SMR harddrive suitable for archive storage - not a generic PMR = harddrive. So the Seagate Archive HDD is suitable for makings backups = and writing huge files like 1TB images which you write from A to Z. SMR = drives are notoriously slow when it comes to non-contiguous writes, such = as writing small files. >>=20 >> You can read warnings about SMR and the Seagate Archive HDD in = particular everywhere on the web. Have you missed them? >>=20 >> Slightly exaggerated: your SMR-drive is more like a tapestreamer than = a real harddrive. It should be used to store enormous files and used for = 'cold storage'. >>=20 >> Read more about the Seagate Archive HDD on its website: = http://www.seagate.com/enterprise-storage/hard-disk-drives/archive-hdd/ >>=20 >> To be honest, it is the worst harddrive one can buy today for the = purpose of regular storage (hot storage). For cold storage, such as = backups like tapestreamers do the drive is decent, but not good by any = means. 1,33TB per platter 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. >>=20 >> Regards, >> CiPHER >>=20 > _______________________________________________ > freebsd-fs@freebsd.org mailing list > https://lists.freebsd.org/mailman/listinfo/freebsd-fs > To unsubscribe, send any mail to "freebsd-fs-unsubscribe@freebsd.org"