how to enable NCQ on Intel ESB2 AHCI SATA?controller/ST31000340NS

Anton Yuzhaninov citrin at
Thu Mar 24 14:38:16 UTC 2011

On Wed, 23 Mar 2011 16:37:11 -0500, Dan Nelson wrote:
DN> If you do a verbose boot, you should get a couple more lines printed:
DN> ahci0: Caps: 64bit NCQ SNTF AL CLO 3Gbps PM PMD SSC PSC 32cmd CCC EM 6ports
DN> ahci0: Caps2:
DN> ahci0: EM Caps: ALHD XMT SMB LED
DN> If you see NCQ in your Caps line, then queueing should be supported by the
DN> controller.  Looking at the ahci.c source, there is a quirk "AHCI_Q_NONCQ"
DN> that disables NCQ, but it it only used for VIA VT8251 chips.

It seems to be NCQ not supported by this controller:
ahci0: AHCI v1.10 with 6 3Gbps ports, Port Multiplier supported
ahci0: Caps: 64bit ALP AL 3Gbps PM SSC PSC 32cmd 6ports
ahci0: Caps2:

 Anton Yuzhaninov

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