From owner-freebsd-doc Fri Aug 23 4:30:21 2002 Delivered-To: freebsd-doc@hub.freebsd.org Received: from mx1.FreeBSD.org (mx1.FreeBSD.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 97ECC37B401 for ; Fri, 23 Aug 2002 04:30:09 -0700 (PDT) Received: from freefall.freebsd.org (freefall.FreeBSD.org [216.136.204.21]) by mx1.FreeBSD.org (Postfix) with ESMTP id CDAC143E7B for ; Fri, 23 Aug 2002 04:30:08 -0700 (PDT) (envelope-from gnats@FreeBSD.org) Received: from freefall.freebsd.org (gnats@localhost [127.0.0.1]) by freefall.freebsd.org (8.12.4/8.12.4) with ESMTP id g7NBU2JU033415 for ; Fri, 23 Aug 2002 04:30:02 -0700 (PDT) (envelope-from gnats@freefall.freebsd.org) Received: (from gnats@localhost) by freefall.freebsd.org (8.12.4/8.12.4/Submit) id g7NBU2PF033414; Fri, 23 Aug 2002 04:30:02 -0700 (PDT) Received: from mx1.FreeBSD.org (mx1.FreeBSD.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 1265737B400 for ; Fri, 23 Aug 2002 04:26:57 -0700 (PDT) Received: from milan.hitnet.rwth-aachen.de (milan.hitnet.RWTH-Aachen.DE [137.226.181.144]) by mx1.FreeBSD.org (Postfix) with ESMTP id 5DA2443E6A for ; Fri, 23 Aug 2002 04:26:56 -0700 (PDT) (envelope-from chris@milan.hitnet.rwth-aachen.de) Received: by milan.hitnet.rwth-aachen.de (Postfix, from userid 1001) id 003B4ABC7; Fri, 23 Aug 2002 13:26:54 +0200 (CEST) Message-Id: <20020823112654.003B4ABC7@milan.hitnet.rwth-aachen.de> Date: Fri, 23 Aug 2002 13:26:54 +0200 (CEST) From: Christian Brueffer Reply-To: Christian Brueffer To: FreeBSD-gnats-submit@FreeBSD.org X-Send-Pr-Version: 3.113 Subject: docs/41934: [PATCH] Several fixes for handbook/vinum/chapter.sgml Sender: owner-freebsd-doc@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.org >Number: 41934 >Category: docs >Synopsis: [PATCH] Several fixes for handbook/vinum/chapter.sgml >Confidential: no >Severity: non-critical >Priority: low >Responsible: freebsd-doc >State: open >Quarter: >Keywords: >Date-Required: >Class: doc-bug >Submitter-Id: current-users >Arrival-Date: Fri Aug 23 04:30:01 PDT 2002 >Closed-Date: >Last-Modified: >Originator: Christian Brueffer >Release: FreeBSD 4.6-STABLE i386 >Organization: >Environment: System: FreeBSD milan.hitnet.rwth-aachen.de 4.6-STABLE FreeBSD 4.6-STABLE #2: Fri Jun 28 12:47:08 CEST 2002 chris@milan.hitnet.rwth-aachen.de:/usr/obj/usr/src/sys/LORIEN i386 >Description: There are two patches attached: The first one contains actual fixes, the second one contains three whitespace fixes. - Add missing tags - Fix an enumeration - Fix a typo - 15000rpm disks have been around for some time, so change some numbers accordingly ;-) >How-To-Repeat: >Fix: --- vinum.fixes.diff begins here --- --- chapter.sgml Thu Aug 22 13:36:27 2002 +++ chapter.sgml.fixes Fri Aug 23 13:07:28 2002 @@ -55,7 +55,7 @@ Disks are getting bigger, but so are data storage requirements. - Often you ill find you want a file system that is bigger than the disks + Often you will find you want a file system that is bigger than the disks you have available. Admittedly, this problem is not as acute as it was ten years ago, but it still exists. Some systems have solved this by creating an abstract device which stores its data on a number of disks. @@ -70,7 +70,7 @@ disks. Current disk drives can transfer data sequentially at up to - 30 MB/s, but this value is of little importance in an environment + 70 MB/s, but this value is of little importance in an environment where many independent processes access a drive, where they may achieve only a fraction of these values. In such cases it is more interesting to view the problem from the viewpoint of the disk @@ -85,10 +85,10 @@ Consider a typical transfer of about 10 kB: the current generation of - high-performance disks can position the heads in an average of 6 ms. The - fastest drives spin at 10,000 rpm, so the average rotational latency - (half a revolution) is 3 ms. At 30 MB/s, the transfer itself takes about - 350 μs, almost nothing compared to the positioning time. In such a + high-performance disks can position the heads in an average of 3.5 ms. The + fastest drives spin at 15,000 rpm, so the average rotational latency + (half a revolution) is 1.75 ms. At 30 MB/s, the transfer itself takes about + 150 μs, almost nothing compared to the positioning time. In such a case, the effective transfer rate drops to a little over 1 MB/s and is clearly highly dependent on the transfer size. @@ -151,7 +151,7 @@ For example, the first 256 sectors may be stored on the first disk, the next 256 sectors on the next disk and so on. After filling the last disk, the process repeats until the disks are full. This mapping is called - striping or RAID-0. + striping or RAID-0. @@ -250,7 +250,7 @@ - Compared to mirroring, RAID-5 has the advantage of requiring + Compared to mirroring, RAID-5 has the advantage of requiring significantly less storage space. Read access is similar to that of striped organizations, but write access is significantly slower, approximately 25% of the read performance. If one drive fails, the array @@ -470,7 +470,7 @@ the system automatically assigns names derived from the plex name by adding the suffix .sx, where x is the number of the subdisk in the plex. Thus - Vinum gives this subdisk the name myvol.p0.s0 + Vinum gives this subdisk the name myvol.p0.s0. @@ -736,8 +736,8 @@ - The directories /dev/vinum/plex and - /dev/vinum/sd, + The directories /dev/vinum/plex, + /dev/vinum/sd, and /dev/vinum/rsd, which contain block device nodes for each plex and block and character device nodes respectively for each subdisk. --- vinum.fixes.diff ends here --- --- vinum.whitespace.diff begins here --- --- chapter.sgml.fixes Fri Aug 23 13:07:28 2002 +++ chapter.sgml.whitespace Fri Aug 23 13:19:26 2002 @@ -53,7 +53,6 @@ addresses these three problems. Let us look at them in more detail. Various solutions to these problems have been proposed and implemented: - Disks are getting bigger, but so are data storage requirements. Often you will find you want a file system that is bigger than the disks you have available. Admittedly, this problem is not as acute as it was @@ -89,7 +88,7 @@ fastest drives spin at 15,000 rpm, so the average rotational latency (half a revolution) is 1.75 ms. At 30 MB/s, the transfer itself takes about 150 μs, almost nothing compared to the positioning time. In such a - case, the effective transfer rate drops to a little over 1 MB/s and is + case, the effective transfer rate drops to a little over 1 MB/s and is clearly highly dependent on the transfer size. The traditional and obvious solution to this bottleneck is @@ -233,7 +232,7 @@ RAID-5An alternative solution is parity, implemented in the RAID levels 2, 3, 4 and 5. Of these, - RAID-5 is the most interesting. As implemented + RAID-5 is the most interesting. As implemented in Vinum, it is a variant on a striped organization which dedicates one block of each stripe to parity of the other blocks: As implemented by Vinum, a RAID-5 plex is similar to a --- vinum.whitespace.diff ends here --- >Release-Note: >Audit-Trail: >Unformatted: To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-doc" in the body of the message