From owner-freebsd-stable Fri May 3 10:21:49 2002 Delivered-To: freebsd-stable@freebsd.org Received: from unagi.cybernothing.org (unagi.cybernothing.org [205.158.174.211]) by hub.freebsd.org (Postfix) with ESMTP id 3322037B422 for ; Fri, 3 May 2002 10:21:27 -0700 (PDT) Received: from twinlark.arctic.org ([208.44.199.239]) by unagi.cybernothing.org (8.11.3/8.10.1/JDF) with ESMTP id g43HLRK69785 for ; Fri, 3 May 2002 10:21:27 -0700 (PDT) Received: (qmail 21602 invoked by uid 1347); 2 May 2002 14:25:49 -0000 Date: 2 May 2002 14:25:49 -0000 Message-ID: <20020502142549.21601.qmail@twinlark.arctic.org> From: atk2@arctic.org To: freebsd-stable@FreeBSD.ORG Subject: dd of=/dev/eide_drive bs=8192 if=/dev/mem kills system Sender: owner-freebsd-stable@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.ORG I have 4.5-stable (updated it last night to get the ata 133 support for my disk drive). I was doing a bit of crude benchmark and used dd if=/dev/ad0s2e bs=8192 of=/dev/null to test read speed (iostat -c 100 indicates about 40MB/sec sustained (i.e., not cache) - if it is accurate) Anyways I then tried to test write speed with dd of=/dev/dev/ad0s2e bs=8192 if=/dev/mem and the system hanged. This was an unmounted slice - yea I know if it worked it would have killed the slice - but the slice is unused so I didn't care). I'm not overly concern that the above killed the system as it isn't needed for daily use -- just noting it in case it is a kernel bug... (note kernel didn't panic - it hanged - I waited about 5 minutes then did a reset -- nothing responded during that time including mouse (was running X) and hdd light on case was off) Alan To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-stable" in the body of the message