From mboxrd@z Thu Jan 1 00:00:00 1970 From: Rick Jones Subject: Re: Network performance degradation from 2.6.11.12 to 2.6.16.20 Date: Fri, 22 Sep 2006 09:51:09 -0700 Message-ID: <4514147D.5040803@hp.com> References: <200609181850.22851.ak@suse.de> <20060919.124751.24100694.davem@davemloft.net> <20060922153517.GB24866@ms2.inr.ac.ru> <200609221743.40053.ak@suse.de> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Cc: Alexey Kuznetsov , David Miller , master@sectorb.msk.ru, hawk@diku.dk, harry@atmos.washington.edu, linux-kernel@vger.kernel.org, netdev@vger.kernel.org Return-path: Received: from palrel12.hp.com ([156.153.255.237]:47266 "EHLO palrel12.hp.com") by vger.kernel.org with ESMTP id S932562AbWIVQvN (ORCPT ); Fri, 22 Sep 2006 12:51:13 -0400 To: Andi Kleen In-Reply-To: <200609221743.40053.ak@suse.de> Sender: netdev-owner@vger.kernel.org List-Id: netdev.vger.kernel.org > That came from named. It opens lots of sockets with SIOCGSTAMP. > No idea what it needs that many for. IIRC ISC BIND named opens a socket for each IP it finds on the system. Presumeably in this way it "knows" implicitly the destination IP without using platform-specific recvfrom/whatever extensions and gets some additional parallelism in the stack on SMP systems. Why it needs/wants the timestamps I've no idea, I don't think it gets them that way on all platforms. I suppose the next time I do some named benchmarking I can try to take a closer look in the source. rick jones