Re: iowait boost is broken

[Peter Zijlstra]

On Mon, Jun 07, 2021 at 08:10:32PM +0100, Beata Michalska wrote:
> So back to the expectations.
> The main problem, as I see it, is what do we actually want to achieve with
> the I/O boosting? Is it supposed to compensate the time lost while waiting
> for the I/O request to be completed or is is supposed to optimize the rate
> at which I/O requests are being made. 

The latter, you want to increase the race of submission.

> Do we want to boost I/O bound tasks by
> default, no limits applied  or should we care about balancing performance
> vs power ? And unless those expectations are clearly stated, we might not
> get too far with any changes, really.

You want to not increase power beyond what is needed to match the rate
of processing I suppose.