From owner-freebsd-net Sun Nov 5 18: 8: 7 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 2691237B4C5; Sun, 5 Nov 2000 18:08:04 -0800 (PST) Received: by overlord.e-gerbil.net (Postfix, from userid 1001) id 67241E4EB9; Sun, 5 Nov 2000 21:08:00 -0500 (EST) Received: from localhost (localhost [127.0.0.1]) by overlord.e-gerbil.net (Postfix) with ESMTP id 52EAEE4EB8; Sun, 5 Nov 2000 21:08:00 -0500 (EST) Date: Sun, 5 Nov 2000 21:08:00 -0500 (EST) From: "Richard A. Steenbergen" To: Kris Kennaway Cc: David Greenman , freebsd-net@FreeBSD.ORG Subject: Re: tcp sendspace/recvspace In-Reply-To: <20001105175722.A8886@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: > Perhaps it was a bug, but I used to see e.g. FTP transfers which were > running at full speed totally monopolizing my modem bandwidth (then a > 14.4k), and other sessions not being able to receive their "fair > share". Tweaking net.inet.tcp.recvspace to give only a second or two > worth of data transfer reduced the latency to acceptable levels. > > Maybe this has been fixed by now - I haven't noticed it since I > upgraded to a 56k modem. I'll try increasing my system to 32768 > and see if it has any effect. Interesting... Most likely thats just the effect of having a slow speed link which takes a long time to serialize data. Especially if you have large packets, they will monopolize the time on the link and make interactive sessions painfully sluggish. This is where WFQ comes in handy. Sounds like what you were doing was intentionally tuning down the performance to sub-optimal so that it wouldn't be lagged. Intelligent queueing seems like a better solution, but turning the socket buffer to 32768 should have no negative impact. -- 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