From owner-freebsd-fs@freebsd.org Mon Jan 21 14:13:03 2019 Return-Path: Delivered-To: freebsd-fs@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id 22EB714AADE6 for ; Mon, 21 Jan 2019 14:13:03 +0000 (UTC) (envelope-from borjam@sarenet.es) Received: from cu01176b.smtpx.saremail.com (cu01176b.smtpx.saremail.com [195.16.151.151]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by mx1.freebsd.org (Postfix) with ESMTPS id 6F2198B399 for ; Mon, 21 Jan 2019 14:13:02 +0000 (UTC) (envelope-from borjam@sarenet.es) Received: from [172.16.8.5] (unknown [192.148.167.11]) by proxypop01.sare.net (Postfix) with ESMTPA id 5F3169DCA45; Mon, 21 Jan 2019 15:12:59 +0100 (CET) Content-Type: text/plain; charset=us-ascii Mime-Version: 1.0 (Mac OS X Mail 12.2 \(3445.102.3\)) Subject: Re: ZFS on Hardware RAID From: Borja Marcos In-Reply-To: <1691666278.63816.1547976245836.JavaMail.zimbra@gausus.net> Date: Mon, 21 Jan 2019 15:12:56 +0100 Cc: andy thomas , freebsd-fs Content-Transfer-Encoding: quoted-printable Message-Id: References: <1180280695.63420.1547910313494.JavaMail.zimbra@gausus.net> <92646202.63422.1547910433715.JavaMail.zimbra@gausus.net> <1691666278.63816.1547976245836.JavaMail.zimbra@gausus.net> To: Maciej Jan Broniarz X-Mailer: Apple Mail (2.3445.102.3) X-Rspamd-Queue-Id: 6F2198B399 X-Spamd-Bar: / Authentication-Results: mx1.freebsd.org; spf=pass (mx1.freebsd.org: domain of borjam@sarenet.es designates 195.16.151.151 as permitted sender) smtp.mailfrom=borjam@sarenet.es X-Spamd-Result: default: False [-0.58 / 15.00]; ARC_NA(0.00)[]; RCVD_VIA_SMTP_AUTH(0.00)[]; NEURAL_HAM_MEDIUM(-0.34)[-0.340,0]; FROM_HAS_DN(0.00)[]; RCPT_COUNT_THREE(0.00)[3]; R_SPF_ALLOW(-0.20)[+ip4:195.16.150.0/23]; MV_CASE(0.50)[]; MIME_GOOD(-0.10)[text/plain]; RCVD_TLS_LAST(0.00)[]; DMARC_NA(0.00)[sarenet.es]; NEURAL_SPAM_SHORT(0.54)[0.545,0]; NEURAL_HAM_LONG(-0.98)[-0.982,0]; TO_MATCH_ENVRCPT_SOME(0.00)[]; TO_DN_ALL(0.00)[]; MX_GOOD(-0.01)[cached: smtp.sarenet.es]; RCVD_IN_DNSWL_NONE(0.00)[151.151.16.195.list.dnswl.org : 127.0.10.0]; IP_SCORE(0.01)[country: ES(0.05)]; FROM_EQ_ENVFROM(0.00)[]; R_DKIM_NA(0.00)[]; MIME_TRACE(0.00)[0:+]; ASN(0.00)[asn:3262, ipnet:195.16.128.0/19, country:ES]; MID_RHS_MATCH_FROM(0.00)[]; RCVD_COUNT_TWO(0.00)[2] X-BeenThere: freebsd-fs@freebsd.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Filesystems List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 21 Jan 2019 14:13:03 -0000 > On 20 Jan 2019, at 10:24, Maciej Jan Broniarz = wrote: >=20 > Hi, >=20 > I am thinking about the scenario with ZFS on single disks configured = to RAID0 by hw raid. > Please correct me, if i'm wrong, but HW Raid uses a dedicated unit to = process all RAID related work (eg. parity checks). > With ZFS the job is done by CPU. How significant is the performance = loss in that particular case? Modern CPUs are supercomputers. ZFS performs amazingly well even with = the puny CPUs found in some small computers like the HP MIcroservers. And there is another advantage with ZFS running on the main processor: = end to end error detection and recovery, especially if you are using ECC memory. Borja.