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Date: Fri, 18 Feb 2011 19:44:30 -0800
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Subject: Re: [RFC v2] mac80211: implement eBDP algorithm to fight bufferbloat
From: Nathaniel Smith <njs@pobox.com>
To: "John W. Linville" <linville@tuxdriver.com>
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Cc: bloat-devel@lists.bufferbloat.net, johannes@sipsolutions.net,
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On Fri, Feb 18, 2011 at 1:21 PM, John W. Linville
<linville@tuxdriver.com> wrote:
> + =C2=A0 =C2=A0 =C2=A0 /* grab timestamp info for buffer control estimate=
s */
> + =C2=A0 =C2=A0 =C2=A0 tserv =3D ktime_sub(ktime_get(), skb->tstamp);
[...]
> + =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 ewma_add(&sta->sdata->=
qdata[q].tserv_ns_avg,
> + =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =
=C2=A0 =C2=A0ktime_to_ns(tserv));

I think you're still measuring how long it takes one packet to get
from the end of the queue to the beginning, rather than measuring how
long it takes each packet to go out?

-- Nathaniel