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From: John Yates <john@yates-sheets.org>
Date: Mon, 6 Jan 2020 10:47:50 -0500
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Cc: Johannes Berg <johannes@sipsolutions.net>, 
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Subject: Re: [Make-wifi-fast] [PATCH v5] mac80211: Switch to a virtual
 time-based airtime scheduler
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On Mon, Jan 6, 2020 at 10:20 AM Toke H=C3=B8iland-J=C3=B8rgensen <toke@redh=
at.com> wrote:
> Or do a middle ground thing where we use 32-bit arithmetic
> for the per-station weights, but go to 64-bit for the weight sum? I
> don't really have a good grip on how much of a performance impact we're
> talking about here, so I'm not sure which I prefer...

Double width accumulation is very common in many applications.
Double width addition and comparison are _much_ cheaper than
double width multiplication and division.

/john