From owner-freebsd-current Tue Dec 21 13:18:43 1999 Delivered-To: freebsd-current@freebsd.org Received: from khavrinen.lcs.mit.edu (khavrinen.lcs.mit.edu [18.24.4.193]) by hub.freebsd.org (Postfix) with ESMTP id A221C150AF; Tue, 21 Dec 1999 13:18:40 -0800 (PST) (envelope-from wollman@khavrinen.lcs.mit.edu) Received: (from wollman@localhost) by khavrinen.lcs.mit.edu (8.9.3/8.9.3) id QAA94098; Tue, 21 Dec 1999 16:18:30 -0500 (EST) (envelope-from wollman) Date: Tue, 21 Dec 1999 16:18:30 -0500 (EST) From: Garrett Wollman Message-Id: <199912212118.QAA94098@khavrinen.lcs.mit.edu> To: Poul-Henning Kamp Cc: Garrett Wollman , Matthew Dillon , jlemon@FreeBSD.ORG, freebsd-current@FreeBSD.ORG Subject: Re: Odd TCP glitches in new currents In-Reply-To: <16589.945810831@critter.freebsd.dk> References: <199912212100.QAA93975@khavrinen.lcs.mit.edu> <16589.945810831@critter.freebsd.dk> Sender: owner-freebsd-current@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG < said: >> Hmmm. I thought we agreed that 200 msec was the minimum reasonable >> RTO. That code doesn't seem to have made it in. > I assume you mean 20 msec (= 2 tick @ 100 Hz ) ? 200 msec is enough > to get halfway around the globe... No, I mean 200 msec. If you make the RTO be any shorter than that, you'll slow-start every packet you send to a machine which is running delayed-ACK (i.e., almost everyone). The official standard RTO is I think 500 msec, but this might be too high. We have ``bad retransmit recovery'' which is supposed to detect some instances of this and disable slow-start in that case. -GAWollman -- Garrett A. Wollman | O Siem / We are all family / O Siem / We're all the same wollman@lcs.mit.edu | O Siem / The fires of freedom Opinions not those of| Dance in the burning flame MIT, LCS, CRS, or NSA| - Susan Aglukark and Chad Irschick To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-current" in the body of the message