From mboxrd@z Thu Jan 1 00:00:00 1970 From: Thomas Graf Subject: Re: [PATCH openvswitch v3] netlink: Implement & enable memory mapped netlink i/o Date: Thu, 05 Dec 2013 23:08:31 +0100 Message-ID: <52A0F95F.4010402@redhat.com> References: <1d9af26b2798901c68ae9aef704d6313b71d3287.1386069453.git.tgraf@redhat.com> <20131204163328.GE30874@nicira.com> <529F6475.3090903@redhat.com> <20131204180818.GB16940@nicira.com> <529FA334.4050202@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Cc: Ben Pfaff , "dev@openvswitch.org" , netdev , Daniel Borkmann , ffusco@redhat.com, fleitner@redhat.com, Cong Wang To: Jesse Gross Return-path: Received: from mx1.redhat.com ([209.132.183.28]:54501 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751871Ab3LEWqm (ORCPT ); Thu, 5 Dec 2013 17:46:42 -0500 In-Reply-To: Sender: netdev-owner@vger.kernel.org List-ID: On 12/04/2013 11:20 PM, Jesse Gross wrote: > If enabling rings on demand can be done cleanly that might be best > solution. To me, it seems difficult to generalize the upcall > characteristics based on port type. It would require to reopen sockets but I don't see that as a major obstacle. > 16K ports/sockets would seem to be a good upper bound. However, there > are a couple of factors that might affect that number in the future. > The first is that port might not be fine-grained enough - for example, > on an uplink port it would be better to look at MAC or IP address to > enforce fairness, which would tend to expand the number of sockets > necessary (although there obviously won't be a 1:1 mapping, which > means that we might have to come up with a more clever assignment > algorithm). The second is that Alex has been working on a userspace > mechanism for enforcing fairness (you probably have seen his recent > patches on the mailing list), which could reduce the number of unique > queues from the kernel. Let's see where we get to with the on demand idea. Defaulting to on is sitll possible if the number of sockets can be limited again.