IDE TCQ

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Dear Jens,

I would like to ask a few simple question: what does it take to make use of this nifty feature?

My example:
I have a box with an ABIT BH6 mainboard (Intel chipset, 2xUATA33 channels), A Leadtek WinFast CMD648 with 2xUATA66 channels, and a Promise Ultra100 TX2 2xUATA100.
I have 3x IBM GXP120 120GB UATA100 IDE HDDs (have read you write these to be capable of TCQ).

First set of questions:
On which of the three different IDE controllers are the disks supposed to be doing TCQ?

Is it limited to UATA100 and up?
Is it limited to specific chipsets?
Maybe a combination of these two?

Is there any list of the disks that support TCQ?
Or does that come compulsory with eg. UATA100?

Second set of questions:
Does it do any good to one-channel-one-disk setups?
Is it supposed to do good to access time, operations/sec, throughput, random reqs rearrangement or what?
Do you have any figures how much TCQ helps performace (e.g. in file serving case)?

Now I see I piled up quite a few questions. Maybe it is more polite to ask you if you can recommend any reading on the topic on the web first?

Maybe I should rather be asking Andre Hedrick about the internals of TCQ?

I have CCd LKML, since others might also like some clarification around IDE TCQ. If you reply, please keep me CCd as well, since I am not subscribed to LKML currently.

Thank you very much!

Peter