From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Miller Subject: Re: RDMA will be reverted Date: Mon, 24 Jul 2006 23:48:53 -0700 (PDT) Message-ID: <20060724.234853.112197982.davem@davemloft.net> References: <20060724.150613.54186472.davem@davemloft.net> <20060725055127.GA5103@2ka.mipt.ru> Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit Cc: rdreier@cisco.com, ak@suse.de, tom@opengridcomputing.com, netdev@vger.kernel.org, akpm@osdl.org Return-path: Received: from dsl027-180-168.sfo1.dsl.speakeasy.net ([216.27.180.168]:22465 "EHLO sunset.davemloft.net") by vger.kernel.org with ESMTP id S1751466AbWGYGsv (ORCPT ); Tue, 25 Jul 2006 02:48:51 -0400 To: johnpol@2ka.mipt.ru In-Reply-To: <20060725055127.GA5103@2ka.mipt.ru> Sender: netdev-owner@vger.kernel.org List-Id: netdev.vger.kernel.org From: Evgeniy Polyakov Date: Tue, 25 Jul 2006 09:51:28 +0400 > On Mon, Jul 24, 2006 at 03:06:13PM -0700, David Miller (davem@davemloft.net) wrote: > > Furthermore, the VJ netchannel gains can be partially obtained from > > generic stateless facilities that we are going to get anyways. > > Networking chips supporting multiple MSI-X vectors, choosen by hashing > > the flow ID, can move TCP processing to "end nodes" which are cpu > > threads in this case, by having each such MSI-X vector target a > > different cpu thread. > > And if that CPU is very busy? > Linux should somehow tell NIC that some CPUs are valid and some are not > right now, but not in a second, so scheduler must be tightly bound with > network internals. Yes, it is research problem. Most of the time, even stateless version will improve things. >>From another viewpoint, even in worst case, it can be no worse than current situation. :) BTW, such dynamic remapping is provided for in the NDIS interfaces. There is an indexing table that is gone through using computed hash to get "cpu number".