From mboxrd@z Thu Jan 1 00:00:00 1970 From: Joe Perches Subject: Re: UDP multicast packet loss not reported if TX ring overrun? Date: Tue, 25 Aug 2009 12:56:01 -0700 Message-ID: <1251230161.24767.57.camel@Joe-Laptop.home> References: Mime-Version: 1.0 Content-Type: text/plain Content-Transfer-Encoding: 7bit Cc: David Stevens , "David S. Miller" , Eric Dumazet , netdev@vger.kernel.org, netdev-owner@vger.kernel.org, niv@linux.vnet.ibm.com, sri@linux.vnet.ibm.com To: Christoph Lameter Return-path: Received: from mail.perches.com ([173.55.12.10]:1370 "EHLO mail.perches.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754836AbZHYT4B (ORCPT ); Tue, 25 Aug 2009 15:56:01 -0400 In-Reply-To: Sender: netdev-owner@vger.kernel.org List-ID: On Tue, 2009-08-25 at 15:15 -0400, Christoph Lameter wrote: > On Tue, 25 Aug 2009, David Stevens wrote: > > Christoph Lameter wrote on 08/25/2009 06:48:24 > > AM: > > > On Mon, 24 Aug 2009, Sridhar Samudrala wrote: > > > > If we count these drops as qdisc drops, should we also count them as > > IP OUTDISCARDS? > > > Yes. > > Actually, no. (!) > > IP_OUTDISCARDS should count the packets IP dropped, not > > anything dropped at a lower layer (which, in general, it > > is not aware of). If you count these in multiple layers, > > then you don't really know who dropped it. > They need to be accounted at the qdisc level though. It's probably useful to be able to know when packets and payloads are dropped. It may not be necessary though. It's probably not a fundamental. Chariot, LANforge and apps like it might care, but most all other apps might not care at all. Maybe these should be allowed with a CONFIG.