From owner-freebsd-performance@FreeBSD.ORG Thu Apr 10 15:32:22 2003 Return-Path: Delivered-To: freebsd-performance@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id DF09B37B401; Thu, 10 Apr 2003 15:32:22 -0700 (PDT) Received: from stork.mail.pas.earthlink.net (stork.mail.pas.earthlink.net [207.217.120.188]) by mx1.FreeBSD.org (Postfix) with ESMTP id 2732643F93; Thu, 10 Apr 2003 15:32:22 -0700 (PDT) (envelope-from tlambert2@mindspring.com) Received: from pool0274.cvx40-bradley.dialup.earthlink.net ([216.244.43.19] helo=mindspring.com) by stork.mail.pas.earthlink.net with asmtp (SSLv3:RC4-MD5:128) (Exim 3.33 #1) id 193kaf-0007Qy-00; Thu, 10 Apr 2003 15:32:18 -0700 Message-ID: <3E95F03C.2A01561D@mindspring.com> Date: Thu, 10 Apr 2003 15:29:16 -0700 From: Terry Lambert X-Mailer: Mozilla 4.79 [en] (Win98; U) X-Accept-Language: en MIME-Version: 1.0 To: Mattias Pantzare References: <20030410171640.C44793B2@porter.dc.luth.se> <3E95E446.73B7E510@mindspring.com> <3E95E8E9.3080102@ludd.luth.se> Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit X-ELNK-Trace: b1a02af9316fbb217a47c185c03b154d40683398e744b8a4c964df480dfbc21ce9d14358040a3b86a8438e0f32a48e08350badd9bab72f9c350badd9bab72f9c cc: bj@dc.luth.se cc: freebsd-hackers@freebsd.org cc: freebsd-performance@freebsd.org cc: Eric Anderson cc: David Gilbert Subject: Re: tcp_output starving -- is due to mbuf get delay? X-BeenThere: freebsd-performance@freebsd.org X-Mailman-Version: 2.1.1 Precedence: list List-Id: Performance/tuning List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 10 Apr 2003 22:32:23 -0000 Mattias Pantzare wrote: > > The products that Jeffrey Hsu and I and Alfred and Jon Mini > > worked on at a previous company had no problems at all on a > > 1Gbit/S saturating the link, even through a VLAN trunk through > > Cisco and one other less intelligent switch (i.e. two switches > > and a VLAN trunk). > > A key factor here is that the testst where on a link with a 20ms > round-tip time, and using a singel TCP connection. So the switches > where in addition to a few routers on a 10Gbit/s network. Sorry, but tis is not a factor. If you think it is, then you are running with badly tuned send and receive maximum window sizes. Latency = pool retention time = queue size -- Terry