From owner-freebsd-hackers Wed Nov 27 6:51:59 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 11BFC37B401 for ; Wed, 27 Nov 2002 06:51:57 -0800 (PST) Received: from van-laarhoven.org (ap-z-5ab8.adsl.wanadoo.nl [212.129.218.184]) by mx1.FreeBSD.org (Postfix) with SMTP id B278F43E9C for ; Wed, 27 Nov 2002 06:51:55 -0800 (PST) (envelope-from n_hibma@van-laarhoven.org) Received: (qmail 529 invoked from network); 27 Nov 2002 14:51:54 -0000 Received: from uitsmijter.van-laarhoven.org (n?hibma@10.66.0.1) by uitsmijter.van-laarhoven.org with SMTP; 27 Nov 2002 14:51:54 -0000 Date: Wed, 27 Nov 2002 15:51:54 +0100 (CET) From: Nick Hibma To: Tomas Pluskal Cc: "freebsd-hackers@freebsd.org" Subject: Re: umass driver speed In-Reply-To: <20021127141637.A343-100000@localhost.localdomain> Message-ID: <20021127155133.W99600-100000@uitsmijter.van-laarhoven.org> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII 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 The ZIP Drive is USB as well? Are you using a UHCI controller (dmesg)? Nick > > Hello, > > It seems to me that the slowness of umass driver is not caused by msdosfs. > I know about the msdosfs problems, for example when I run dd from my ZIP > drive (with FAT) with request size of 2048, it's extremely slow. When I > change request size to 64K, it gains normal speed (about 1MB/s). > > But with my camera (umass), I get: > > # dd if=/dev/da0s1 of=/tmp/nikon bs=2048 count=10 > 10+0 records in > 10+0 records out > 20480 bytes transferred in 0.379587 secs (53953 bytes/sec) > > # dd if=/dev/da0s1 of=/tmp/nikon bs=4096 count=10 > 10+0 records in > 10+0 records out > 40960 bytes transferred in 0.719477 secs (56930 bytes/sec) > > # dd if=/dev/da0s1 of=/tmp/nikon bs=8192 count=10 > 10+0 records in > 10+0 records out > 81920 bytes transferred in 1.389069 secs (58975 bytes/sec) > > # dd if=/dev/da0s1 of=/tmp/nikon bs=65536 count=10 > 10+0 records in > 10+0 records out > 655360 bytes transferred in 10.832928 secs (60497 bytes/sec) > > # dd if=/dev/da0s1 of=/tmp/nikon bs=524288 count=1 > 1+0 records in > 1+0 records out > 524288 bytes transferred in 8.668605 secs (60481 bytes/sec) > > The speed is nearly the same, no matter about the request size. > > What do you think about it ? > > Tomas > > On Sat, 24 Aug 2002, Nick Hibma wrote: > > > > > Yes, unfortunately it is a known issue in the msdos file system. The > > requests it makes are too small for the driver to take advantage of the > > speed of USB. > > > > Nick > > -- n_hibma@van-laarhoven.org http://www.van-laarhoven.org/ n_hibma@FreeBSD.org http://www.etla.net/~n_hibma/ To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hackers" in the body of the message