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Date: Fri, 27 Oct 2006 19:53:58 -0600
From: Scott Long <scottl@samsco.org>
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To: AT Matik <asstec@matik.com.br>
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Cc: freebsd-scsi@freebsd.org, "Kenneth D. Merry" <ken@kdm.org>
Subject: Re: Why is SCSI so much faster with the write cache off (than ATA)?
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AT Matik wrote:
> On Friday 27 October 2006 19:04, Kenneth D. Merry wrote:
>> work well.  Is tagged queueing enabled on the ATA disks you're testing?  Is
>> it the old-style queueing or NCQ?
> 
> 
> hi
> 
> since it seems you're into this can you give further info how NCQ is related 
> to the OS? how we can manage NCQ on OS level?
> 
> Joćo
> 
> 

FreeBSD doesn't support either form of ATA/SATA tagged queueing, yet.

Scott