Re: Why is NCQ enabled by default by libata? (2.6.20)

Alan Cox
2007-03-29T20:32:19Z

O> writes, and sending down multiple untagged cached writes that complete
> immediately and actually hit the disk later? Either way the host keeps
> sending writes to the disk until it's buffers are full, and the disk is
> constantly trying to commit those buffers to the media in the most
> optimal order.

On the controller side primarily you get to queue commands which means
you don't have a dead time period between the completion interrupt and
the next command being issued. Those times add up even when there is a
disk cache buffering the output