Scheduler question

Daniel O'Connor doconnor at
Mon Feb 7 12:38:26 UTC 2011

On 07/02/2011, at 21:07, Ivan Voras wrote:
>>> I'm also interested in raw device vs file system access!
>> Oops, sorry.. I just tried that now but it doesn't improve things :(
> 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)
> 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 -
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