From owner-freebsd-net Sun Nov 5 17:36:20 2000 Delivered-To: freebsd-net@freebsd.org Received: from overlord.e-gerbil.net (e-gerbil.net [207.91.110.247]) by hub.freebsd.org (Postfix) with ESMTP id A602E37B4CF; Sun, 5 Nov 2000 17:36:17 -0800 (PST) Received: by overlord.e-gerbil.net (Postfix, from userid 1001) id 2CB9DE4EB9; Sun, 5 Nov 2000 20:36:14 -0500 (EST) Received: from localhost (localhost [127.0.0.1]) by overlord.e-gerbil.net (Postfix) with ESMTP id 18689E4EB8; Sun, 5 Nov 2000 20:36:14 -0500 (EST) Date: Sun, 5 Nov 2000 20:36:14 -0500 (EST) From: "Richard A. Steenbergen" To: Kris Kennaway Cc: David Greenman , freebsd-net@FreeBSD.ORG Subject: Re: tcp sendspace/recvspace In-Reply-To: <20001105172400.A8778@citusc17.usc.edu> Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-freebsd-net@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.org On Sun, 5 Nov 2000, Kris Kennaway wrote: > On Sun, Nov 05, 2000 at 02:02:44PM -0800, David Greenman wrote: > > I've been messing around with the net.inet.tcp.sendspace and > > net.inet.tcp.recvspace parameters on ftp.freesoftware.com and have found > > that there is a significant performance improvement when increasing these > > to 32768 bytes. Apparantly there are enough systems out there with higher > > window maxes that it really does make a difference. By significant > > improvement, I mean about a average of a 20% increase in Mbps per user, > > and this was just the change over a 30 minute period with lots of connections > > still using the old 16K values. > > Any objections to increasing the defaults in FreeBSD to 32K? > > Won't this impact the latency of multiple connections over a slow PPP link? Thats what the congestion window is for. Any limitation of transmits based on the advertised memory limitation window is totally improper. -- Richard A Steenbergen http://www.e-gerbil.net/humble PGP Key ID: 0x138EA177 (67 29 D7 BC E8 18 3E DA B2 46 B3 D8 14 36 FE B6) To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-net" in the body of the message