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From: "Daniel O'Connor" <doconnor@gsoft.com.au>
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To: Ivan Voras <ivoras@freebsd.org>
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On 07/02/2011, at 21:07, Ivan Voras wrote:
>>> I'm also interested in raw device vs file system access!
>>=20
>> Oops, sorry.. I just tried that now but it doesn't improve things :(
>=20
> Meaning: you still get jitter?

Yes, well I didn't measure the read frequency but it dropped out =
(stopped streaming due to a full FIFO) no less often.

>> I am writing directly to /dev/ad10 but stressing /dev/ad14 (sudo tar =
-cf /dev/null /local0)
>=20
> Can you do only one of those things? I.e. leave all the file systems
> alone and just do something like 'diskinfo -vt /dev/ad14'?

OK, I wrote the data to /dev/null from USB and ran diskutil in a loop =
and it doesn't drop out.

--
Daniel O'Connor software and network engineer
for Genesis Software - http://www.gsoft.com.au
"The nice thing about standards is that there
are so many of them to choose from."
  -- Andrew Tanenbaum
GPG Fingerprint - 5596 B766 97C0 0E94 4347 295E E593 DC20 7B3F CE8C