How do I use NCQ of Intel X25-E(SSD) on ahci(4)?

Wes Peters barnaclewes at
Tue Dec 15 09:36:28 UTC 2009

On Wed, Nov 18, 2009 at 7:46 AM, Norikatsu Shigemura <nork at> wrote:
> Hi Alexander!
>        I have a Intel 64GB SSD(X25-E) and a Western Digital Caviar Green
>        1TB HDD (WD10EADS), and use them on ahci(4).  ahci(4) can use NCQ
>        of WD10EADS, but doesn't use NCQ of X25-E.

How useful is NCQ on an SSD?  Isn't the primary thrust of NCQ to allow
the disk to reorder writes to optimize the seek pattern?

Against stupidity the very gods Themselves contend in vain.
                                         Friedrich Schiller

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