From owner-freebsd-hackers Fri Dec 6 8:50:37 2002 Delivered-To: freebsd-hackers@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 3816D37B406 for ; Fri, 6 Dec 2002 08:50:32 -0800 (PST) Received: from genius.tao.org.uk (genius.tao.org.uk [212.135.162.51]) by mx1.FreeBSD.org (Postfix) with ESMTP id D72C843EC2 for ; Fri, 6 Dec 2002 08:50:30 -0800 (PST) (envelope-from joe@genius.tao.org.uk) Received: by genius.tao.org.uk (Postfix, from userid 100) id 38B424654; Thu, 5 Dec 2002 23:03:47 +0000 (GMT) Date: Thu, 5 Dec 2002 23:03:47 +0000 From: Josef Karthauser To: Nick Hibma Cc: Tomas Pluskal , "freebsd-hackers@freebsd.org" Subject: Re: umass driver speed Message-ID: <20021205230347.GA11476@genius.tao.org.uk> Mail-Followup-To: Josef Karthauser , Nick Hibma , Tomas Pluskal , "freebsd-hackers@freebsd.org" References: <20021127151016.V315-100000@localhost.localdomain> <20021127154231.T99600-100000@uitsmijter.van-laarhoven.org> Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="k1lZvvs/B4yU6o8G" Content-Disposition: inline In-Reply-To: <20021127154231.T99600-100000@uitsmijter.van-laarhoven.org> User-Agent: Mutt/1.5.1i Sender: owner-freebsd-hackers@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.ORG --k1lZvvs/B4yU6o8G Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Wed, Nov 27, 2002 at 03:49:59PM +0100, Nick Hibma wrote: > > This is the debug output of > > #dd if=3D/dev/da0s1c of=3D/tmp/data bs=3D65536 count=3D3 > > > > umass0:0:0:0:XPT_SCSI_IO: cmd: 0x1e, flags: 0xc0, 6b cmd/0b data/32b se= nse > > umass0:0:0:0:XPT_SCSI_IO: cmd: 0x28, flags: 0x40, 10b cmd/512b data/32b= sense > > umass0:0:0:0:XPT_SCSI_IO: cmd: 0x28, flags: 0x40, 10b cmd/512b data/32b= sense >=20 > The 3 64k blocks you asked for are below. >=20 > > umass0:0:0:0:XPT_SCSI_IO: cmd: 0x28, flags: 0x40, 10b cmd/65536b data/3= 2b sense > > umass0:0:0:0:XPT_SCSI_IO: cmd: 0x28, flags: 0x40, 10b cmd/65536b data/3= 2b sense > > umass0:0:0:0:XPT_SCSI_IO: cmd: 0x28, flags: 0x40, 10b cmd/65536b data/3= 2b sense >=20 > > umass0:0:0:0:XPT_SCSI_IO: cmd: 0x35, flags: 0xc0, 10b cmd/0b data/32b s= ense > > umass0:0:0:0:XPT_SCSI_IO: cmd: 0x1e, flags: 0xc0, 6b cmd/0b data/32b se= nse >=20 > So, the blocks are fetched in 64k blocks. Two options: Either the USB > stack does not chain the transfers in such a way that the device can run > at full performance or otherwise the device chokes on the transfers and > forces the chain of transfers to be delayed till the next frame. There > is a 'bandwidth reclamation' feature in the NetBSD stack in the UHCI > driver of which I do not know whether they made it into the USB stack. >=20 It did make it into -current, but it's not in -stable yet I believe. Joe --=20 Josef Karthauser (joe@tao.org.uk) http://www.josef-k.net/ FreeBSD (cvs meister, admin and hacker) http://www.uk.FreeBSD.org/ Physics Particle Theory (student) http://www.pact.cpes.sussex.ac.uk/ =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D An eclectic mix of fact an= d theory. =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D --k1lZvvs/B4yU6o8G Content-Type: application/pgp-signature Content-Disposition: inline -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.2.1 (FreeBSD) iEYEARECAAYFAj3v21IACgkQXVIcjOaxUBbcvACePQqOavkalXmGyExwN60d06Yw 9AYAnRm1+lzBCl/f72CfQEy2keia+N1K =6D2f -----END PGP SIGNATURE----- --k1lZvvs/B4yU6o8G-- To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hackers" in the body of the message