From owner-freebsd-fs Wed Oct 4 15:14:31 2000 Delivered-To: freebsd-fs@freebsd.org Received: from mail.webmonster.de (datasink.webmonster.de [194.162.162.209]) by hub.freebsd.org (Postfix) with SMTP id 0512E37B66D for ; Wed, 4 Oct 2000 15:14:28 -0700 (PDT) Received: (qmail 88448 invoked by uid 1000); 4 Oct 2000 22:14:26 -0000 Date: Thu, 5 Oct 2000 00:14:26 +0200 From: "Karsten W. Rohrbach" To: Robert Watson Cc: Alex Povolotsky , freebsd-fs@freebsd.org Subject: Re: Specialised storage system? Message-ID: <20001005001426.D88159@rohrbach.de> Reply-To: karsten@rohrbach.de References: <20001004150052.E32009@mail.over.ru> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-Mailer: Mutt 1.0i In-Reply-To: ; from rwatson@freebsd.org on Wed, Oct 04, 2000 at 08:28:43AM -0400 X-Arbitrary-Number-Of-The-Day: 42 X-Sender: karsten@rohrbach.de Sender: owner-freebsd-fs@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.org Robert Watson(rwatson@freebsd.org)@Wed, Oct 04, 2000 at 08:28:43AM -0400: > > On Wed, 4 Oct 2000, Alex Povolotsky wrote: > > > I'm looking to try writing high-performance storage system for mail, > > intended to boost large free mail system. > > > > It seems to me that such a system will give enough performance gains while > > requiring less effor that a full-featured file system, and may provide good > > basis for writing a file-system later. > > > > Maybe someone will point me at existing attempts and/or join effort? > > It might be interesting to adapt the Cyrus mail server to use IFS, Adrian > Chadd's FFS-lite for backend storage. IFS only supports inode numbers as > filenames, meaning constant lookup time for a vnode, eliminating the cost > of directory and namespace management. He developed it for use with so, this would be the lower layer of the namesys approach as far as i get it, right? i think reiserfs tries to do this in a hierarchical manner, mapping the tree with meta information onto a flat namespace with the files containing payload data. and hell, a lot more, but anyway ;-) > Squid, but you could imagine using it as a backing store for other > services that provide their own meta-data management (AFS/Coda caches, > news server backends, Cyrus mail server stuff, etc). Most of these would > require improved service-layer database management, as both news servers > and cyrus rely on the directory layout to indicate that a message belongs > to a particular folder; putting that in a central database would realize > real performance benefits however. Coda and AFS could probably be > trivially modified to use IFS. if your 'application' has some nice strategy for mapping files into a flat namespace (say: numbered files, 1-d) this might be a nice idea. implementing some storage on that for rdbms purpose would be a good point to start. for mail, i think, you need the abstraction layer in-between to have hierarchical constructs in directory and metadata and of course permissions. > > Robert N M Watson > > robert@fledge.watson.org http://www.watson.org/~robert/ > PGP key fingerprint: AF B5 5F FF A6 4A 79 37 ED 5F 55 E9 58 04 6A B1 > TIS Labs at Network Associates, Safeport Network Services > > > > > To Unsubscribe: send mail to majordomo@FreeBSD.org > with "unsubscribe freebsd-fs" in the body of the message -- > May the source be with you! KR433/KR11-RIPE -- http://www.webmonster.de -- ftp://ftp.webmonster.de To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-fs" in the body of the message