From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jarek Poplawski <jarkao2@gmail.com>
Subject: Re: [RFC PATCH] sched: Fix resource limiting in pfifo_fast
Date: Sun, 30 Aug 2009 09:47:05 +0200
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Cc: Krishna Kumar <krkumar2@in.ibm.com>, davem@davemloft.net,
	netdev@vger.kernel.org
To: Eric Dumazet <eric.dumazet@gmail.com>
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Eric Dumazet wrote, On 08/30/2009 08:54 AM:

> Krishna Kumar a =E9crit :
>> From: Krishna Kumar <krkumar2@in.ibm.com>
>>
>> pfifo_fast_enqueue has this check:
>>         if (skb_queue_len(list) < qdisc_dev(qdisc)->tx_queue_len) {
>>
>> which allows each band to enqueue upto tx_queue_len skbs for a
>> total of 3*tx_queue_len skbs. I am not sure if this was the
>> intention of limiting in qdisc.
>=20
> Yes I noticed that and said to myself :
> This was to let high priority packets have their own limit,
> independent on fact that low priority packets filled their queue.


Good point, but then logically it could be something like:
  if (skb_queue_len(list) < qdisc_dev(qdisc)->tx_queue_len / 3)

Of course, there is a backward compatibility question, plus
an sch_prio consistency question.

Jarek P.