Re: libata in 2.4.24?

Jeff Garzik
2003-12-02T18:08:31Z

On Tue, Dec 02, 2003 at 09:40:48AM -0800, Mike Fedyk wrote:
> There are PATA drives that do TCQ too, but you have to look for that feature
> specifically. IDE TCQ is in 2.6, but is still experemental. I think Jens
> Axboe was the one working on it IIRC. He would have more details.

Let us distinguish three types of TCQ:
1) PATA drive-side TCQ (now called "legacy TCQ")
2) Controller-side TCQ
3) SATA drive/controller-side TCQ ("first party DMA")

libata will never support #1, which is what 2.6 supports in experimental
option.

libata will support #2 very soon, and will support #3 when hardware is
available.

> > Do the new SATA drives and controllers provide a solution to this?
>
> It's not SATA specific, and I'm not sure if any ide controller can support
> TCQ or if only a specific list are compatible.

The TCQ you are thinking of has been deprecated by the people who make
IDE drives ;-)

Jeff