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Dennis Moore wrote:
As I recall when overlap/queuing was proposed for ATA devices (X3T10-95-258) that the handling of command reordering was left to the drive with no restrictions. It was the equivalent of SCSI task attribute SIMPLE and mode UNRESTRICTED. I can't find anything in current documentation that confirms or denies that. Are drives that support queuing today doing unrestricted reordering? Are SATA NCQ devices going to do unrestricted reordering? Any help is most appreciated.
In the lack of further information, one must -assume- that the devices are doing unrestricted reordering.
And I think it's likely, given that unrestricted ordering gives the ATA device the most flexibility in optimizing the outstanding ATA commands.
Jeff
