From owner-freebsd-hackers  Wed Dec 13 13:44:53 2000
From owner-freebsd-hackers@FreeBSD.ORG  Wed Dec 13 13:44:46 2000
Return-Path: <owner-freebsd-hackers@FreeBSD.ORG>
Delivered-To: freebsd-hackers@freebsd.org
Received: from hand.dotat.at (sfo-gw.covalent.net [207.44.198.62])
	by hub.freebsd.org (Postfix) with ESMTP id 091A337B6CA
	for <hackers@freebsd.org>; Wed, 13 Dec 2000 13:44:43 -0800 (PST)
Received: from fanf by hand.dotat.at with local (Exim 3.15 #3)
	id 146Jgy-0006aF-00; Wed, 13 Dec 2000 21:44:04 +0000
Date: Wed, 13 Dec 2000 21:44:04 +0000
From: Tony Finch <dot@dotat.at>
To: Dag-Erling Smorgrav <des@ofug.org>
Cc: Gustavo Vieira Goncalves Coelho Rios <gustavo@ifour.com.br>,
	hackers@FreeBSD.ORG
Subject: Re: very big mail spool directory
Message-ID: <20001213214404.P71002@hand.dotat.at>
References: <3A368F8C.1918684F@ifour.com.br> <xzpsnns4jvx.fsf@flood.ping.uio.no>
Mime-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
User-Agent: Mutt/1.2i
In-Reply-To: <xzpsnns4jvx.fsf@flood.ping.uio.no>
Organization: Covalent Technologies, Inc
Sender: fanf@dotat.at
Sender: owner-freebsd-hackers@FreeBSD.ORG
Precedence: bulk
X-Loop: FreeBSD.ORG

Dag-Erling Smorgrav <des@ofug.org> wrote:
>
>If you only have half a million users, pick a prime number K close to
>the square root of the expected number of users (724 in your case -
>closest primes are 719 and 727), create that many bucket directories,
>and place each user in bucket ID mod K.

Why a prime number? All you need is an even spread, and given that
user IDs are usually allocated sequentially any modulus will do.

Tony.
-- 
f.a.n.finch    fanf@covalent.net    dot@dotat.at
"Plan 9 deals with the resurrection of the dead."


To Unsubscribe: send mail to majordomo@FreeBSD.org
with "unsubscribe freebsd-hackers" in the body of the message