From owner-freebsd-hackers@FreeBSD.ORG Tue Feb 21 16:55:00 2006 Return-Path: X-Original-To: hackers@freebsd.org Delivered-To: freebsd-hackers@FreeBSD.ORG Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 55EE716A420 for ; Tue, 21 Feb 2006 16:55:00 +0000 (GMT) (envelope-from rea@rea.mbslab.kiae.ru) Received: from rea.mbslab.kiae.ru (rea.mbslab.kiae.ru [144.206.177.25]) by mx1.FreeBSD.org (Postfix) with ESMTP id DC3F343D46 for ; Tue, 21 Feb 2006 16:54:59 +0000 (GMT) (envelope-from rea@rea.mbslab.kiae.ru) Received: from rea.mbslab.kiae.ru (localhost [127.0.0.1]) by rea.mbslab.kiae.ru (Postfix) with ESMTP id DDAB3BE5F for ; Tue, 21 Feb 2006 19:54:56 +0300 (MSK) Received: by rea.mbslab.kiae.ru (Postfix, from userid 1000) id BB5E9BDC6; Tue, 21 Feb 2006 19:54:56 +0300 (MSK) Date: Tue, 21 Feb 2006 19:54:56 +0300 From: FreeLSD To: hackers@freebsd.org Message-ID: <20060221165456.GZ44603@rea.mbslab.kiae.ru> MIME-Version: 1.0 Content-Type: text/plain; charset=koi8-r Content-Disposition: inline User-Agent: mutt-ng/devel-r581 (FreeBSD) X-AV-Checked: Yes! Cc: Subject: FreeBSD-6 and em interface speed X-BeenThere: freebsd-hackers@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Technical Discussions relating to FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 21 Feb 2006 16:55:00 -0000 Good day! I've obtained the following strang results with the em Ethernet interface speeds on a 6.1-PRERELEASE: Polling on: UDP stream to FreeBSD: 327843.84 Kbit/sec, TCP stream to FreeBSD: 524550.12 Kbit/sec. Polling off: UDP stream to FreeBSD: 740409.38 Kbit/sec, TCP stream to FreeBSD: 794348.44 Kbit/sec. It is funny that TCP speed is greater than UDP. It can be related to the hardware, not to the OS, because I've seen such behaviour on a linux-2.6. But on linux-2.4 with the same hardware as for FreeBSD and with the same source host I've got UDP stream to Linux: 927891.44 Kbit/sec, TCP stream to Linux: 850202.50 Kbit/sec. The figures are higher and UDP rate > TCP rate. The questions: can anyone explain the relation 'TCP rate > UDP rate'? Why polling slows down the interface? And can FreeBSD stack can be tuned to get the Linux performance? Kernel config deviations from GENERIC: options SCHED_ULE options ADAPTIVE_GIANT device pf device pflog device pfsync System is running at hz = 1000. Thanks! -- rea I often think it's a pity that Noah and his party didn't miss the boat. -Mark Twain