From owner-freebsd-arch Tue Jun 11 15: 8:46 2002 Delivered-To: freebsd-arch@freebsd.org Received: from fledge.watson.org (fledge.watson.org [204.156.12.50]) by hub.freebsd.org (Postfix) with ESMTP id B7FFC37B400; Tue, 11 Jun 2002 15:08:34 -0700 (PDT) Received: from fledge.watson.org (fledge.pr.watson.org [192.0.2.3]) by fledge.watson.org (8.12.3/8.12.3) with SMTP id g5BM88b5016253; Tue, 11 Jun 2002 18:08:09 -0400 (EDT) (envelope-from robert@fledge.watson.org) Date: Tue, 11 Jun 2002 18:08:08 -0400 (EDT) From: Robert Watson X-Sender: robert@fledge.watson.org To: Poul-Henning Kamp Cc: arch@freebsd.org Subject: Re: Statement of architectural direction: disklabel64 / GPT. In-Reply-To: <98152.1023733690@critter.freebsd.dk> Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-freebsd-arch@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.ORG Sounds like a good idea to me. Imagine, everyone using the same partition scheme -- there must be some snag :-) Robert N M Watson FreeBSD Core Team, TrustedBSD Projects robert@fledge.watson.org Network Associates Laboratories On Mon, 10 Jun 2002, Poul-Henning Kamp wrote: > > The issue of 32->64 bit migration of struct disklabel has come up > now that daddr_t is 64 bit wide. > > I have pondered the issue and researched what material I could find > and come to the conclusion that we should not make a 64bit version > of struct disklabel, but instead use the industry standard GPT format. > > A 64bit BSD style disklabel would in best case be a {Free,Net,Open}BSD > thing, worst case just a FreeBSD thing. Either way I will argue > that it would be a private format. > > Unless it can provide functionality otherwise not possible there > is no point in adding a new private format. > > The GPT handles 16k partitions, 64 bit addressing, has decently > checksummed and redundant meta-data and space for per partition > meta-data. > > I can't think of anything else we might need, so I have decided > not to make a 64bit disklabel format and instead use the GPT format. > > This may result in us using the GPT format in ways not anticipated > by the standard (ie: embedded in a native partition on some odd-ball > platform) but that should not give any more or less trouble than > embedding a disklabel64 there. > > We will need to support GPT for at least ia64 anyway, and I predict > that it will sneak into ia32 RSN as well, so this is actually less > work for us than doing a disklabel64. > > Any objections ? > > -- > Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 > phk@FreeBSD.ORG | TCP/IP since RFC 956 > FreeBSD committer | BSD since 4.3-tahoe > Never attribute to malice what can adequately be explained by incompetence. > > To Unsubscribe: send mail to majordomo@FreeBSD.org > with "unsubscribe freebsd-arch" in the body of the message > To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-arch" in the body of the message