Re: [Make-wifi-fast] [RFC] mac80211: Add airtime fairness accounting

From: David Lang <david@lang.hm>
To: Johannes Berg <johannes@sipsolutions.net>
Cc: "Toke Høiland-Jørgensen" <toke@toke.dk>,
	make-wifi-fast@lists.bufferbloat.net,
	linux-wireless@vger.kernel.org
Subject: Re: [Make-wifi-fast] [RFC] mac80211: Add airtime fairness accounting
Date: Mon, 9 Oct 2017 00:50:20 -0700 (PDT)	[thread overview]
Message-ID: <alpine.DEB.2.02.1710090047220.7677@nftneq.ynat.uz> (raw)
In-Reply-To: <1507533328.26041.12.camel@sipsolutions.net>

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On Mon, 9 Oct 2017, Johannes Berg wrote:

> On Sat, 2017-10-07 at 13:22 +0200, Toke Høiland-Jørgensen wrote:
>
>> Guess you are right that it will be difficult to get a completely
>> accurate number. But as David Lang notes, as long as we are off by
>> the same amount for all stations, that is fine - we're just
>> interested in relative numbers.
>
> That's not quite true though, you'd overestimate most on stations that
> are using aggregation, assuming you take into account the whole frame
> exchange sequence time. But maybe giving less than their fair share to
> fast stations isn't really that much of a problem.

how much error does this introduce?
Compared to the stations using 802.11b, this is a trivial difference.

That's why I said perfect is the enemy of good enough. Yes, it would be ideal to 
get the airtime from the driver, but if the driver doesn't provide it, I think 
ignoring aggregation in the name of simplicity is 'good enough'

David Lang