Re: [LSF/MM TOPIC][LSF/MM ATTEND] NAPI polling for block drivers

Johannes Thumshirn
2017-01-18T13:51:56Z

On Tue, Jan 17, 2017 at 06:38:43PM +0200, Sagi Grimberg wrote:
>
> >Just for the record, all tests you've run are with the upper irq_poll_budget of
> >256 [1]?
>
> Yes, but that's the point, I never ever reach this budget because
> I'm only processing 1-2 completions per interrupt.
>
> >We (Hannes and me) recently stumbed accross this when trying to poll for more
> >than 256 queue entries in the drivers we've been testing.

s/stumbed/stumbled/

>
> What do you mean by stumbed? irq-poll should be agnostic to the fact
> that drivers can poll more than their given budget?

So what you say is you saw a consomed == 1 [1] most of the time?

[1] from http://git.infradead.org/nvme.git/commitdiff/eed5a9d925c59e43980047059fde29e3aa0b7836

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