From owner-freebsd-hackers Sat Nov 6 12: 2:21 1999 Delivered-To: freebsd-hackers@freebsd.org Received: from funkthat.com (adsl-63-195-54-213.dsl.snfc21.pacbell.net [63.195.54.213]) by hub.freebsd.org (Postfix) with ESMTP id 13D3314F8F for ; Sat, 6 Nov 1999 12:02:16 -0800 (PST) (envelope-from gurney_j@efn.org) Received: (from jmg@localhost) by funkthat.com (8.9.1/8.8.7) id MAA14368; Sat, 6 Nov 1999 12:01:58 -0800 (PST) Message-ID: <19991106120158.26688@hydrogen.fircrest.net> Date: Sat, 6 Nov 1999 12:01:58 -0800 From: John-Mark Gurney To: Jonathan Lemon Cc: hackers@freebsd.org Subject: Re: writing much slower than reading... References: <199911061708.LAA25924@free.pcs> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-Mailer: Mutt 0.69 In-Reply-To: <199911061708.LAA25924@free.pcs>; from Jonathan Lemon on Sat, Nov 06, 1999 at 11:08:58AM -0600 Reply-To: John-Mark Gurney Organization: Cu Networking X-Operating-System: FreeBSD 3.0-RELEASE i386 X-PGP-Fingerprint: B7 EC EF F8 AE ED A7 31 96 7A 22 B3 D8 56 36 F4 X-Files: The truth is out there X-URL: http://resnet.uoregon.edu/~gurney_j/ Sender: owner-freebsd-hackers@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG Jonathan Lemon scribbled this message on Nov 6: > Try doing `iostat 1' while doing the transfers. This is what I see here: > > tty da0 da1 da2 cpu > tin tout KB/t tps MB/s KB/t tps MB/s KB/t tps MB/s us ni sy in id > TEST A: 0.00 0 0.00 64.00 119 7.47 0.00 0 0.00 0 0 3 0 97 > TEST B: 0.00 0 0.00 64.00 419 26.18 0.00 0 0.00 0 0 1 0 99 > TEST C: 0.00 0 0.00 64.00 95 5.94 64.00 95 5.94 0 0 1 0 99 > TEST D: 63.84 338 21.05 64.00 343 21.41 0.00 0 0.00 0 0 26 2 72 > > TEST A: (writing) dd if=/dev/zero of=/dev/rda1 bs=1m count=400 > TEST B: (reading) dd if=/dev/rda1 of=/dev/zero bs=1m count=400 > TEST C: (read & write) dd if=/dev/rda1 of=/dev/rda2 bs=1m count=400 > TEST D: (read raw & write fs) dd if=/dev/rda1 of=trash bs=1m count=400 tty wd0 cpu tin tout KB/t tps MB/s us ni sy in id TEST A: 113.50 182 20.19 0 0 27 1 72 TEST B: 113.63 202 22.41 0 0 2 2 96 TEST C: 114.07 174 19.40 0 0 2 1 97 TEST D: 81.92 224 17.89 0 0 48 3 48 since I only have on drive, TEST C was dd of=/dev/rwd0s1g if=/dev/rwd0s1g bs=1m count=400, and TEST D was writing to the same drive that I was reading from, no softupdates enabled... and I was doing all testing on /dev/rwd0s1g so I could write... > System is a Dell Poweredge 4300 PIII/600, all disks are Seagate ST39103LC. k6-2/250 (100mhz system bus), IBM-DPTA-372730 > Disk da0 (where the trash file is written) has softupdates enabled. This > is on a week old -current. > > I'm suprised by the last line. Writing to the filesystem is faster > than writing to the raw device? I must be missing something here. I'm surprised at the last two lines... I didn't think that I would be able to push/pull that much data at once, but considering that it didn't have to seek far it isn't that surprising... hmmmm... could this be a deficency in the IDE driver?? sounds like I need to test the new ata driver and see if it performs better... -- John-Mark Gurney Voice: +1 408 975 9651 Cu Networking "The soul contains in itself the event that shall presently befall it. The event is only the actualizing of its thought." -- Ralph Waldo Emerson To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hackers" in the body of the message