From owner-freebsd-hackers Thu Dec 14 3:28:55 2000 From owner-freebsd-hackers@FreeBSD.ORG Thu Dec 14 03:28:52 2000 Return-Path: Delivered-To: freebsd-hackers@freebsd.org Received: from flood.ping.uio.no (flood.ping.uio.no [129.240.78.31]) by hub.freebsd.org (Postfix) with ESMTP id 7533F37B400 for ; Thu, 14 Dec 2000 03:28:46 -0800 (PST) Received: (from des@localhost) by flood.ping.uio.no (8.9.3/8.9.3) id MAA71399; Thu, 14 Dec 2000 12:28:40 +0100 (CET) (envelope-from des@ofug.org) Sender: des@ofug.org X-URL: http://www.ofug.org/~des/ X-Disclaimer: The views expressed in this message do not necessarily coincide with those of any organisation or company with which I am or have been affiliated. To: Tony Finch Cc: Gustavo Vieira Goncalves Coelho Rios , hackers@FreeBSD.ORG Subject: Re: very big mail spool directory References: <3A368F8C.1918684F@ifour.com.br> <20001213214404.P71002@hand.dotat.at> From: Dag-Erling Smorgrav Date: 14 Dec 2000 12:28:40 +0100 In-Reply-To: Tony Finch's message of "Wed, 13 Dec 2000 21:44:04 +0000" Message-ID: Lines: 12 User-Agent: Gnus/5.0802 (Gnus v5.8.2) Emacs/20.4 MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Sender: owner-freebsd-hackers@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG Tony Finch writes: > Why a prime number? All you need is an even spread, and given that > user IDs are usually allocated sequentially any modulus will do. Because a prime number is less likely to cause an imbalance in where files are actually stored on disk - just like you want an odd (and preferably prime) stripe size on RAIDs to (amongst other reasons) avoid having all the superblock backups end up on the same disk. DES -- Dag-Erling Smorgrav - des@ofug.org To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hackers" in the body of the message