From owner-freebsd-questions@freebsd.org Wed Aug 5 19:57:08 2020 Return-Path: Delivered-To: freebsd-questions@mailman.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.nyi.freebsd.org (Postfix) with ESMTP id 1B55E3A7D3B for ; Wed, 5 Aug 2020 19:57:08 +0000 (UTC) (envelope-from 4250.82.1d4c2000762114f.82fa46285328f34ceb05e10749970133@email-od.com) Received: from s1-b0c6.socketlabs.email-od.com (s1-b0c6.socketlabs.email-od.com [142.0.176.198]) (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 4BMMpW3Drcz49Jv for ; Wed, 5 Aug 2020 19:57:07 +0000 (UTC) (envelope-from 4250.82.1d4c2000762114f.82fa46285328f34ceb05e10749970133@email-od.com) DKIM-Signature: v=1; a=rsa-sha256; d=email-od.com;i=@email-od.com;s=dkim; c=relaxed/relaxed; q=dns/txt; t=1596657427; x=1599249427; h=content-transfer-encoding:content-type:mime-version:references:in-reply-to:message-id:subject:cc:to:from:date:x-thread-info; bh=DUvmcO0xJ8tqTtYLP3qcUS/HV4fk0a3f2DVFghYAGBA=; b=b406By7YPcsZtYIc4s7elFfDDc0ox74aB8QXRrGrRkUyS4qL3AZDwbC4L9mVYKn0mxjRRvVGaljFoPgEvys14ZLUzZS2Q/GywTz3TPKSWVPRp7kO7OYOOolcIK5vZnpU72ntTBNLIofKTBPUrUU71qLmIW6G0ffQU+J48zzIM3Q= X-Thread-Info: NDI1MC45Mi4xZDRjMjAwMDc2MjExNGYuZnJlZWJzZC1xdWVzdGlvbnM9ZnJlZWJzZC5vcmc= Received: from r3.us-east-1.aws.in.socketlabs.com (r3.us-east-1.aws.in.socketlabs.com [142.0.191.3]) by mxsg2.email-od.com with ESMTP(version=Tls12 cipher=Aes256 bits=256); Wed, 5 Aug 2020 15:56:57 -0400 Received: from smtp.lan.sohara.org (EMTPY [185.202.17.215]) by r3.us-east-1.aws.in.socketlabs.com with ESMTP(version=Tls12 cipher=Aes256 bits=256); Wed, 5 Aug 2020 15:56:56 -0400 Received: from [192.168.63.1] (helo=steve.lan.sohara.org) by smtp.lan.sohara.org with smtp (Exim 4.94 (FreeBSD)) (envelope-from ) id 1k3PWw-000DKt-Iv; Wed, 05 Aug 2020 20:56:54 +0100 Date: Wed, 5 Aug 2020 20:56:54 +0100 From: Steve O'Hara-Smith To: freebsd-questions@freebsd.org Cc: Polytropon Subject: Re: Question re ZFS with mixed drive speeds & types Message-Id: <20200805205654.c884ed8ef72b0cef048e5072@sohara.org> In-Reply-To: <20200805204546.d1bf410e.freebsd@edvax.de> References: <575C4647-8F20-4187-9B74-2D509D31A249@gmail.com> <4fefedad-5b2a-11b8-7b22-3b6162f0404f@holgerdanske.com> <20200805182636.GD48435@mithril> <20200805204546.d1bf410e.freebsd@edvax.de> X-Mailer: Sylpheed 3.7.0 (GTK+ 2.24.32; amd64-portbld-freebsd12.0) X-Clacks-Overhead: "GNU Terry Pratchett" Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-Rspamd-Queue-Id: 4BMMpW3Drcz49Jv X-Spamd-Bar: -- Authentication-Results: mx1.freebsd.org; dkim=pass header.d=email-od.com header.s=dkim header.b=b406By7Y; dmarc=none; spf=pass (mx1.freebsd.org: domain of 4250.82.1d4c2000762114f.82fa46285328f34ceb05e10749970133@email-od.com designates 142.0.176.198 as permitted sender) smtp.mailfrom=4250.82.1d4c2000762114f.82fa46285328f34ceb05e10749970133@email-od.com X-Spamd-Result: default: False [-2.26 / 15.00]; ARC_NA(0.00)[]; RWL_MAILSPIKE_VERYGOOD(0.00)[142.0.176.198:from]; R_DKIM_ALLOW(-0.20)[email-od.com:s=dkim]; NEURAL_HAM_MEDIUM(-1.01)[-1.008]; FROM_HAS_DN(0.00)[]; TO_DN_SOME(0.00)[]; MV_CASE(0.50)[]; R_SPF_ALLOW(-0.20)[+ip4:142.0.176.0/20]; MIME_GOOD(-0.10)[text/plain]; DMARC_NA(0.00)[sohara.org]; NEURAL_HAM_LONG(-1.04)[-1.044]; RCVD_COUNT_THREE(0.00)[4]; TO_MATCH_ENVRCPT_SOME(0.00)[]; DKIM_TRACE(0.00)[email-od.com:+]; RCPT_COUNT_TWO(0.00)[2]; RCVD_IN_DNSWL_NONE(0.00)[142.0.176.198:from]; NEURAL_HAM_SHORT(-0.51)[-0.506]; FORGED_SENDER(0.30)[steve@sohara.org,4250.82.1d4c2000762114f.82fa46285328f34ceb05e10749970133@email-od.com]; MIME_TRACE(0.00)[0:+]; RCVD_TLS_LAST(0.00)[]; ASN(0.00)[asn:7381, ipnet:142.0.176.0/22, country:US]; FROM_NEQ_ENVFROM(0.00)[steve@sohara.org,4250.82.1d4c2000762114f.82fa46285328f34ceb05e10749970133@email-od.com]; MID_RHS_MATCH_FROM(0.00)[] X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.33 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 05 Aug 2020 19:57:08 -0000 On Wed, 5 Aug 2020 20:45:46 +0200 Polytropon wrote: > On Wed, 5 Aug 2020 20:26:36 +0200, Jacques Foucry wrote: > > I remember the same thing when Sun demostrate us ZFS (I was a Sunkskill > > at this time). But I never tried. > > Sounds a bit like HSM - hierarchical storage management, I remember a lecture about a variant on that where the layering went all way from RAM to tape seamlessly, the idea was that data was inherently persistent and the virtual address space was huge. > So decades old stuff is "new" again... ;-) That lecture would have been late 1970s. -- Steve O'Hara-Smith