From owner-freebsd-performance@FreeBSD.ORG  Mon Aug 28 00:11:47 2006
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Date: Sun, 27 Aug 2006 19:11:43 -0500
From: "Rick C. Petty" <rick-freebsd@kiwi-computer.com>
To: "Jin Guojun \[VFFS\]" <j_guojun@lbl.gov>
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Cc: freebsd-performance@freebsd.org, hardware@freebsd.org
Subject: Re: reduce interrupt rate for CD/DVD drive(r)
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On Sun, Aug 27, 2006 at 04:37:29PM -0700, Jin Guojun [VFFS] wrote:
> I have difficulty to get CD/DVD write speed above 1.6MB/s  (10x for CD, 
> or 1.1x for DVD).
> The problem seems to be the interrupt rate is high (70-80% of CPU) for 
> CD/DVD drive(r).

What's the value of the "hw.ata.atapi_dma" sysctl?

-- Rick C. Petty