From owner-freebsd-questions@FreeBSD.ORG Fri Sep 5 15:03:49 2003 Return-Path: Delivered-To: freebsd-questions@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 9627C16A4BF; Fri, 5 Sep 2003 15:03:49 -0700 (PDT) Received: from HAL9000.homeunix.com (12-233-57-131.client.attbi.com [12.233.57.131]) by mx1.FreeBSD.org (Postfix) with ESMTP id 804BD44013; Fri, 5 Sep 2003 15:03:48 -0700 (PDT) (envelope-from das@FreeBSD.ORG) Received: from HAL9000.homeunix.com (localhost [127.0.0.1]) by HAL9000.homeunix.com (8.12.9/8.12.9) with ESMTP id h85M3dG7020167; Fri, 5 Sep 2003 15:03:39 -0700 (PDT) (envelope-from das@FreeBSD.ORG) Received: (from das@localhost) by HAL9000.homeunix.com (8.12.9/8.12.9/Submit) id h85M3bxF020166; Fri, 5 Sep 2003 15:03:37 -0700 (PDT) (envelope-from das@FreeBSD.ORG) Date: Fri, 5 Sep 2003 15:03:37 -0700 From: David Schultz To: David Gilbert Message-ID: <20030905220337.GA20142@HAL9000.homeunix.com> Mail-Followup-To: David Gilbert , Poul-Henning Kamp , Petri Helenius , Max Clark , freebsd-hackers@freebsd.org, freebsd-performance@freebsd.org, Dan Nelson , freebsd-questions@freebsd.org References: <3F5647F3.5080502@he.iki.fi> <64330.1062619621@critter.freebsd.dk> <16216.36410.889440.499438@canoe.velocet.net> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <16216.36410.889440.499438@canoe.velocet.net> cc: Poul-Henning Kamp cc: Petri Helenius cc: Max Clark cc: freebsd-hackers@FreeBSD.ORG cc: freebsd-performance@FreeBSD.ORG cc: Dan Nelson cc: freebsd-questions@FreeBSD.ORG Subject: Re: 20TB Storage System X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.1 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 05 Sep 2003 22:03:49 -0000 On Fri, Sep 05, 2003, David Gilbert wrote: > >>>>> "Poul-Henning" == Poul-Henning Kamp writes: > > Poul-Henning> In message <3F5647F3.5080502@he.iki.fi>, Petri Helenius > Poul-Henning> writes: > >> fsck problem should be gone with less inodes and less blocks since > >> if I read the code correctly, memory is consumed according to used > >> inodes and blocks so having like 20000 inodes and 64k blocks should > >> allow you to build 5-20T filesystem and actually fsck them. > > Poul-Henning> I am not sure I would advocate 64k blocks yet. > > Poul-Henning> I tend to stick with 32k block, 4k fragment myself. > > Poul-Henning> This is a problem which is in the cross-hairs for 6.x > > That reminds me... has anyone thought of designing the system to have > more than 8 frags per block? Increasingly, for large file > performance, we're pushing up the block size dramatically. This is > with the assumption that large disks will contain large files. > > ... but I havn't seem that, myself. Large arrays that we run tend to > have multiple system images (for diskless or semi-diskless operation) > and many more thousands of users ... all with their usual complement > of small files. > > It strikes me that driving the block size up (as far as 1M) and having > a 256 (or so) fragments might become appropriate. > > We probably also need to address disks with larger block sizes soon, > but that's another issue alltogether. To that end, UFS2 is supposed to be able to support ``jumbo blocks''. The code for that isn't in the tree, but I presume Kirk is working on it.