From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Miller Subject: Re: [PATCH 20/31]: pkt_sched: Perform bulk of qdisc destruction in RCU. Date: Mon, 21 Jul 2008 10:08:21 -0700 (PDT) Message-ID: <20080721.100821.38432201.davem@davemloft.net> References: <20080721164306.GA13131@gondor.apana.org.au> <20080721.095124.89249903.davem@davemloft.net> <20080721170233.GA13417@gondor.apana.org.au> Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit Cc: hadi-fAAogVwAN2Kw5LPnMra/2Q@public.gmane.org, kaber-dcUjhNyLwpNeoWH0uzbU5w@public.gmane.org, netdev-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, johannes-cdvu00un1VgdHxzADdlk8Q@public.gmane.org, linux-wireless-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: herbert-lOAM2aK0SrRLBo1qDEOMRrpzq4S04n8Q@public.gmane.org Return-path: In-Reply-To: <20080721170233.GA13417-lOAM2aK0SrRLBo1qDEOMRrpzq4S04n8Q@public.gmane.org> Sender: linux-wireless-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-Id: netdev.vger.kernel.org From: Herbert Xu Date: Tue, 22 Jul 2008 01:02:33 +0800 > On Mon, Jul 21, 2008 at 09:51:24AM -0700, David Miller wrote: > > > > How so? If the TX hash is well distributed, which it should be, > > it is at least going to approximate the distribution provided by > > the RX hash. > > This is a matter of probabilities :) In general, if the TX hash > and the RX hash are completely unrelated, then the end result of > the hash distribution should be independent of each other (independent > in the probablistic sense). That is, for the flows which have > been RX hashed into one queue, they should be hashed on average > across all queues by the TX hash. Conversely, those that have > been hashed into one TX queue would be distributed across all > RX queues. Theoretically perhaps you are right. Can I at least get some commitment that someone will test that this really is necessary before we add the CPU ID hash option? -- To unsubscribe from this list: send the line "unsubscribe linux-wireless" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html