Messages in this thread | | | Date | Tue, 24 Apr 2007 09:31:03 +0200 | From | Ingo Molnar <> | Subject | Re: [REPORT] cfs-v4 vs sd-0.44 |
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* Rogan Dawes <lists@dawes.za.net> wrote:
> > if (p_to && p->wait_runtime > 0) { > > p->wait_runtime >>= 1; > > p_to->wait_runtime += p->wait_runtime; > > } > > > >the above is the basic expression of: "charge a positive bank balance". > > > > [..] > > > [note, due to the nanoseconds unit there's no rounding loss to worry > > about.] > > Surely if you divide 5 nanoseconds by 2, you'll get a rounding loss?
yes. But not that we'll only truly have to worry about that when we'll have context-switching performance in that range - currently it's at least 2-3 orders of magnitude above that. Microseconds seemed to me to be too coarse already, that's why i picked nanoseconds and 64-bit arithmetics for CFS.
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