From mboxrd@z Thu Jan  1 00:00:00 1970
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Date: Wed,  6 Feb 2008 11:43:47 +0100
From: Kernel Panic <cinap_lenrek@gmx.de>
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To: Fans of the OS Plan 9 from Bell Labs <9fans@cse.psu.edu>
Subject: Re: [9fans] VIA VT8237 SATA/RAID i/o errors, dma doesnt work
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erik quanstrom wrote:

>you may want to try a block size of 64k in your tests.
>this may make a difference.
>
>
thats exactly what the dd based testscript does:

fn rotest {
...
dd -if $1 -of /dev/null -bs $3 &
...
}

...
b=65536

rotest $d $t $b
...


i choose that blocksize because the I/O erros printed by venti
while i first tried to copy arenas showed that blocksize.

i conclude for now that doing paralel io on both drives results
in I/O errors in short time. reading/writing a single drive, the
system hangs/freezes after many hours without a trace.


>- erik
>
>
cinap