[PATCH] nvme: Add weighted-round-robin arbitration support

[Kanchan Joshi]

Different hctx sounds good, and can be used for both polled IO and WRR 
(somewhat more resource-heavy for WRR though). May I know if that work 
is in progress already.
It seems NVMe driver does not have to do much in that scheme-of-things, 
while block layer takes most of the load.

On Tuesday 09 January 2018 10:35 PM, Keith Busch wrote:
> On Tue, Jan 09, 2018 at 07:20:58PM +0530, Kanchan Joshi wrote:
>> It seems to me that some sort of differentiation (among tasks of various
>> classes) during tag allocation is required to handle this. Perhaps, static
>> division of available tags into 4 priority classes needs to be done in block
>> layer.
> 
> Yes, I was thinking either some kind priorty based tag reservation, or
> possibly entirely different hctx's for each priority. The block layer
> currently doesn't provide this kind of separation, but it was mentioned
> the latter might be appropriate for hipri/polled IO, so maybe that idea
> can extend to WRR.
> 
> 
>