From mboxrd@z Thu Jan  1 00:00:00 1970
From: Christoph Lameter <cl@linux-foundation.org>
Subject: Re: UDP multicast packet loss not reported if TX ring overrun?
Date: Tue, 25 Aug 2009 09:48:24 -0400 (EDT)
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Cc: Eric Dumazet <eric.dumazet@gmail.com>,
	Nivedita Singhvi <niv@us.ibm.com>, netdev@vger.kernel.org,
	"David S. Miller" <davem@davemloft.net>
To: Sridhar Samudrala <sri@us.ibm.com>
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On Mon, 24 Aug 2009, Sridhar Samudrala wrote:

> So are you hitting this case with your workload and does this account for all the
> packet losses you are seeing?

Yes.

> If we are dropping the packet and returing NET_XMIT_DROP, should
> we also increment qdisc drop stats (sch->qstats.drops)?

I think so but I am no expert. I was surprised to not even see counter
increments at that level. But I was content to fix up the higher level
tracking to have at least one counter that showed the packet loss.

> If we count these drops as qdisc drops, should we also count them as IP OUTDISCARDS?

Yes.