On Tue, Apr 27, 2010 at 10:36:37AM +0200, Roy Sigurd Karlsbakk wrote: > ----- "Daniel Carosone" <d...@geek.com.au> skrev: > > SAS: Full SCSI TCQ > > SATA: Lame ATA NCQ > > What's so lame about NCQ?
Primarily, the meager number of outstanding requests; write cache is needed to pretend the writes are done straight away and free up the slots for reads. If you want throughput, you want to hand the disk controller as many requests as possible, so it can optimise seek order. If you have especially latency-sensitive requests, you need to manage the queue carefully with either system. -- Dan.
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