From mboxrd@z Thu Jan 1 00:00:00 1970 From: jamal Subject: Re: Network card IRQ balancing with Intel 5000 series chipsets Date: Tue, 26 Dec 2006 17:11:29 -0500 Message-ID: <1167171089.3746.23.camel@localhost> References: <7e63f56c0612240134s452f6510h8483fb31e5efe799@mail.gmail.com> <1167039303.3281.1574.camel@laptopd505.fenrus.org> <7e63f56c0612250326td172f28n532435b23d18b69f@mail.gmail.com> <1167046499.3281.1623.camel@laptopd505.fenrus.org> <7e63f56c0612250454g5520bd6aja0fb9ab2656ff74e@mail.gmail.com> <1167158658.3746.12.camel@localhost> <7e63f56c0612261151y7aa95954hb2a1d47ce130c38d@mail.gmail.com> Reply-To: hadi@cyberus.ca Mime-Version: 1.0 Content-Type: text/plain Content-Transfer-Encoding: 7bit Cc: Arjan van de Ven , netdev@vger.kernel.org Return-path: Received: from wx-out-0506.google.com ([66.249.82.230]:3573 "EHLO wx-out-0506.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932823AbWLZWLd (ORCPT ); Tue, 26 Dec 2006 17:11:33 -0500 Received: by wx-out-0506.google.com with SMTP id h27so3992986wxd for ; Tue, 26 Dec 2006 14:11:32 -0800 (PST) To: Robert Iakobashvili In-Reply-To: <7e63f56c0612261151y7aa95954hb2a1d47ce130c38d@mail.gmail.com> Sender: netdev-owner@vger.kernel.org List-Id: netdev.vger.kernel.org On Tue, 2006-26-12 at 21:51 +0200, Robert Iakobashvili wrote: BTW, turn on PCI-E on in the kernel build and do cat /proc/interupts to see what i mean. > In meanwhile I have removed all userland processes from CPU0, > that handles network card interrupts and all packet-processing (kernel-space). > > Still, it should be some way of CPU-scaling; even for the case of the > only network card. The best way to achieve such balancing is to have the network card help and essentially be able to select the CPU to notify while at the same time considering: a) avoiding any packet reordering - which restricts a flow to be processed to a single CPU at least within a timeframe b) be per-CPU-load-aware - which means to busy out only CPUs which are less utilized Various such schemes have been discussed here but no vendor is making such nics today (search Daves Blog - he did discuss this at one point or other). cheers, jamal