From owner-freebsd-fs Mon May 24 2:18:38 1999 Delivered-To: freebsd-fs@freebsd.org Received: from haldjas.folklore.ee (Haldjas.folklore.ee [193.40.6.121]) by hub.freebsd.org (Postfix) with ESMTP id AAC28151C9 for ; Mon, 24 May 1999 02:18:33 -0700 (PDT) (envelope-from narvi@haldjas.folklore.ee) Received: from haldjas.folklore.ee (haldjas.folklore.ee [172.17.2.1] (may be forged)) by haldjas.folklore.ee (8.8.8/8.8.4) with SMTP id MAA13744; Mon, 24 May 1999 12:18:29 +0300 (EEST) Date: Mon, 24 May 1999 12:18:29 +0300 (EEST) From: Narvi To: Alfred Perlstein Cc: fs@FreeBSD.ORG Subject: Re: reference for filesystem with btree layout? In-Reply-To: Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-freebsd-fs@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.org On Mon, 24 May 1999, Alfred Perlstein wrote: > On Mon, 24 May 1999, Narvi wrote: > > > > > Presently ffs uses ufs code for directory related operations. It should be > > possible (and not too hard at my reading of it back when I had a similar > > idea) to replace them. > > It would change the on disk structure otherwise there would be a lot > of extra IO involved no? > The way I thought of it, it would have been a btree inside an "ordinary" directory file. The on disk directory structure would have two additional fields, right & left which point to the offsets of respective lower brances in the tree. The tree is kept Balanced. But I guess that is just one way. There will be slightly more I/O. > > > also, specifically in FreeBSD, I don't see a reason why a filesystem can't > > > take ownership of multiple block devices, is there a reason? > > > > > > > What's the need? You can stripe the block devices with ccd (or concat > > with vinum) and get the same result. > > the point would be to at runtime add more backing block devices > to expand or migrate the filesystem. > That would require more extensive re-engineering of the FS. > -Alfred > Sander There is no love, no good, no happiness and no future - all these are just illusions. To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-fs" in the body of the message