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Date: Mon, 1 Dec 2003 11:04:37 +0100
From: Hanspeter Roth <hampi@rootshell.be>
To: freebsd-realtime@freebsd.org
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Subject: cdda2wav/cdrecord at highest priority?
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Hello,

cdda2wav and cdrecord from the cdrtools package are trying to run at
highest priority -20. When reading or burning tracks a massive
amount of data is transfered.
Is it a good idea to run them at highest priority?
Does it also make sense on a ATAPI drive with DMA enabled?
Wouldn't a lesser priority, say -12 to -18, suffice?

I have an ATAPI drive which has DMA enabled. When cdda2wav runs on
this drive without the cdda2wav speed limitation the CPU has an
excessive amount of IRQs. While cdda2wav is running the whole screen
freezes. As the speed limitation is decreased (24) the amount of
IRQs also decreases and the screen won't freeze. Also running
cdda2wav at a lower priority (-4) inhibits the screen from freezing.

Wouldn't it make sense to patch cdda2wav and cdrecord from the
cdrtools port in order to run at a lesser priority?

-Hanspeter