Why is SCSI so much faster with the write cache off (than ATA)?

Scott Long scottl at samsco.org
Sat Oct 28 01:54:06 UTC 2006


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?
> 
> João
> 
> 

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

Scott


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