From owner-freebsd-questions@freebsd.org Sat Aug 29 06:21:50 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 240643CEC0F for ; Sat, 29 Aug 2020 06:21:50 +0000 (UTC) (envelope-from 4250.82.1d4c2000a7885da.41f976022203be5622013cf811a50ebc@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 4BdmZj15hpz40PZ for ; Sat, 29 Aug 2020 06:21:48 +0000 (UTC) (envelope-from 4250.82.1d4c2000a7885da.41f976022203be5622013cf811a50ebc@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=1598682109; x=1601274109; h=content-transfer-encoding:content-type:mime-version:references:in-reply-to:message-id:subject:to:from:date:x-thread-info; bh=Mr74UMmV1b1ThElL+TiZy5X197va+3pIygNN3pWjSSY=; b=idtcm81vEC0MDSWFvDStL6CujSzIhiL1mTUFRP3iOLLa8UeYMHbkpuy8Zar5ijqPk/0yZZduK+qaI+7lO6qlJi8XJ4bIub/CZqSQhPT/4Kl4/KKsUvQOakwLYMo6k2TFrCTX3hxq0Qm/nHNTuj0U4iArO7SyFGDdkCjJQv6Ca3M= X-Thread-Info: NDI1MC45Mi4xZDRjMjAwMGE3ODg1ZGEuZnJlZWJzZC1xdWVzdGlvbnM9ZnJlZWJzZC5vcmc= Received: from r2.us-east-1.aws.in.socketlabs.com (r2.us-east-1.aws.in.socketlabs.com [142.0.191.2]) by mxsg2.email-od.com with ESMTP(version=Tls12 cipher=Aes256 bits=256); Sat, 29 Aug 2020 02:21:41 -0400 Received: from smtp.lan.sohara.org (EMTPY [185.202.17.215]) by r2.us-east-1.aws.in.socketlabs.com with ESMTP(version=Tls12 cipher=Aes256 bits=256); Sat, 29 Aug 2020 02:21:41 -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 1kBuF9-000LdW-AK for freebsd-questions@freebsd.org; Sat, 29 Aug 2020 07:21:39 +0100 Date: Sat, 29 Aug 2020 07:21:39 +0100 From: Steve O'Hara-Smith To: freebsd-questions@freebsd.org Subject: Re: (very OT) Ideal partition schemes (history of partitioning) Message-Id: <20200829072139.627a0b3294f20b34ce0c35ff@sohara.org> In-Reply-To: References: 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: 4BdmZj15hpz40PZ X-Spamd-Bar: - Authentication-Results: mx1.freebsd.org; dkim=pass header.d=email-od.com header.s=dkim header.b=idtcm81v; dmarc=none; spf=pass (mx1.freebsd.org: domain of 4250.82.1d4c2000a7885da.41f976022203be5622013cf811a50ebc@email-od.com designates 142.0.176.198 as permitted sender) smtp.mailfrom=4250.82.1d4c2000a7885da.41f976022203be5622013cf811a50ebc@email-od.com X-Spamd-Result: default: False [-1.87 / 15.00]; MID_RHS_MATCH_FROM(0.00)[]; ARC_NA(0.00)[]; R_DKIM_ALLOW(-0.20)[email-od.com:s=dkim]; NEURAL_HAM_MEDIUM(-0.97)[-0.967]; FROM_HAS_DN(0.00)[]; RWL_MAILSPIKE_VERYGOOD(0.00)[142.0.176.198:from]; MV_CASE(0.50)[]; TO_MATCH_ENVRCPT_ALL(0.00)[]; MIME_GOOD(-0.10)[text/plain]; TO_DN_NONE(0.00)[]; DMARC_NA(0.00)[sohara.org]; RCPT_COUNT_ONE(0.00)[1]; NEURAL_HAM_LONG(-0.97)[-0.971]; RCVD_COUNT_THREE(0.00)[4]; R_SPF_ALLOW(-0.20)[+ip4:142.0.176.0/20]; DKIM_TRACE(0.00)[email-od.com:+]; NEURAL_HAM_SHORT(-0.23)[-0.229]; RCVD_IN_DNSWL_NONE(0.00)[142.0.176.198:from]; FORGED_SENDER(0.30)[steve@sohara.org,4250.82.1d4c2000a7885da.41f976022203be5622013cf811a50ebc@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,4250.82.1d4c2000a7885da.41f976022203be5622013cf811a50ebc@email-od.com]; MAILMAN_DEST(0.00)[freebsd-questions] 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: Sat, 29 Aug 2020 06:21:50 -0000 On Fri, 28 Aug 2020 23:08:30 -0400 Aryeh Friedman wrote: > Also why are partitioned need at all? (both currently and historically) For a historical perspective I once saw a home made XENIX box with four 8" floppy drives labelled /, /etc, /usr and /tmp. Back when drives were small it was desirable to have more storage in the filesystem than available on a drive, being able to combine multiple filesystems into a single tree by mounting made it possible to do that seamlessly. Compare and contrast with drive letters as in CP/M, MS/PC-DOS and even still lurking in the latest Windows. A side benefit was that it made it possible to have different options (read only, block sizes, ...) on different mounts and so tune different parts of the tree for the different usage (for an extreme example /tmp is sometimes a memory based file system these days). It was also an enabler for seamless network filesystems from MICNET (which ran over UUCP) to NFS by way of AFS. Today of course a 10TB drive is a consumer item and for most purposes there is no need to split up the tree into multiple filesystems just to have enough space. One consideration though is to prevent a runaway writer from chewing up all the available disc space, having separated filesystems limits the scope to one section of the tree (which can still be a real PITA). Quotas is a more recent solution to the same problem, as is the spaced reserved for root processes in UFS mounts. Personally I tend to use ZFS for almost everything and mount /home (and a few other odds and ends) from my NAS which also runs a lot of jails. This results in a lot of filesystems (especially on the NAS) coming from a small number of pools. The way ZFS uses so many filesystems is mostly useful for the ability to have different filesystem level settings at the mount points. For a contrasting approach there is a commercial distributed filesystem (OneFS) where metadata of that kind (including replication policy) is settable by directory. I won't say too much about it because it pays my wages. As for disk partitioning that's just a way to pretend that one big disk is a set of smaller ones, which is of course useful for many reasons. -- Steve O'Hara-Smith