From owner-freebsd-current@FreeBSD.ORG Mon Oct 27 18:27:29 2003 Return-Path: Delivered-To: freebsd-current@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 0767816A4CE for ; Mon, 27 Oct 2003 18:27:29 -0800 (PST) Received: from fledge.watson.org (fledge.watson.org [204.156.12.50]) by mx1.FreeBSD.org (Postfix) with ESMTP id 2212A43FBD for ; Mon, 27 Oct 2003 18:27:28 -0800 (PST) (envelope-from robert@fledge.watson.org) Received: from fledge.watson.org (localhost [127.0.0.1]) by fledge.watson.org (8.12.9p2/8.12.9) with ESMTP id h9S2QKMg007118; Mon, 27 Oct 2003 21:26:21 -0500 (EST) (envelope-from robert@fledge.watson.org) Received: from localhost (robert@localhost)h9S2QKO0007115; Mon, 27 Oct 2003 21:26:20 -0500 (EST) (envelope-from robert@fledge.watson.org) Date: Mon, 27 Oct 2003 21:26:20 -0500 (EST) From: Robert Watson X-Sender: robert@fledge.watson.org To: Stefan Walter In-Reply-To: <20031027125318.GB1582@kyuzo.dunkelkammer.void> Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII cc: current@FreeBSD.org Subject: Re: GBDE performance on ZIP disks X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.1 Precedence: list List-Id: Discussions about the use of FreeBSD-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 28 Oct 2003 02:27:29 -0000 On Mon, 27 Oct 2003, Stefan Walter wrote: > is there a way to speed up writing to a gbde encrypted ZIP disk? > Copying 37 MB of data to an encrypted disk (in a SCSI drive) that has > been initialized with "newfs -O 2 -U /dev/da1a.bde" takes ~180 seconds, > which is ~200KB/s. Copying the same amount of data to the disk without > using gbde takes ~50 seconds, which is ~740KB/s. > > I guess this problem is similar to the one you have when using msdosfs > on a SCSI ZIP drive, which is also very slow. > > Using a different sector size than the default 512, which is also the > sector size of the media, doesn't seem to be possible and always results > in a "gbde: write sector 0: Operation not permitted". Playing around > with newfs's options didn't help so far, either. How do things look performance-wise if you do a raw sector read comparison with dd at various blocksizes? My recollection is that our msdos code would benefit hugely from the addition of clustering support, but UFS2 with a fragment size matching GBDE's notion shouldn't present the same problem... Robert N M Watson FreeBSD Core Team, TrustedBSD Projects robert@fledge.watson.org Network Associates Laboratories