From owner-freebsd-questions  Tue Nov 26 14:38:46 2002
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From: Matthias Trevarthan <trevarthan@wingnet.net>
Reply-To: trevarthan@wingnet.net
Organization: Urokosodoji, Inc.
To: Dan Nelson <dnelson@allantgroup.com>
Subject: Re: Sony AIT tape position question
Date: Tue, 26 Nov 2002 17:38:37 -0500
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References: <200210301441.55643.trevarthan@wingnet.net> <200211261700.46508.trevarthan@wingnet.net> <20021126223047.GB32468@dan.emsphone.com>
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I'll try that. Any idea where I can get 1G of=20
random data? That's a truckload man. :)

Thanks.


On Tuesday 26 November 2002 17:30, Dan Nelson=20
wrote:
>
> Try generating 1gb of random data, run a "dd
> if=3Drandomdata of=3D/dev/nrsa0 bs=3D1m ; mt rdhpos"
> loop until the tape fills up, and then graph
> the results.  If it's a straight line, you can
> safely use the results of rdhpos as a rough
> tape capacity indicator.  If you were not
> writing completely random data, chances are
> your tape drive's compresion algorithm was
> screwing up your calculations.


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