Re: [PATCH 04/17] sched/fair: Add avg_vruntime

[Peter Zijlstra]

On Tue, Mar 28, 2023 at 04:57:49PM -0700, Josh Don wrote:
> On Tue, Mar 28, 2023 at 4:06 AM Peter Zijlstra <peterz@xxxxxxxxxxxxx> wrote:
> [...]
> > +/*
> > + * Compute virtual time from the per-task service numbers:
> > + *
> > + * Fair schedulers conserve lag: \Sum lag_i = 0
> > + *
> > + * lag_i = S - s_i = w_i * (V - v_i)
> > + *
> > + * \Sum lag_i = 0 -> \Sum w_i * (V - v_i) = V * \Sum w_i - \Sum w_i * v_i = 0
> 
> Small note: I think it would be helpful to label these symbols
> somewhere :) Weight  and vruntime are fairly obvious, but I don't
> think 'S' and 'V' are as clear. Are these non-virtual ideal service
> time, and average vruntime, respectively?

Yep, they are. I'll see what I can do with the comments.