From owner-freebsd-net Sun Nov 28 15: 6:30 1999 Delivered-To: freebsd-net@freebsd.org Received: from implode.root.com (root.com [209.102.106.178]) by hub.freebsd.org (Postfix) with ESMTP id 8826114A2A for ; Sun, 28 Nov 1999 15:06:25 -0800 (PST) (envelope-from dg@implode.root.com) Received: from implode.root.com (localhost [127.0.0.1]) by implode.root.com (8.8.8/8.8.5) with ESMTP id PAA24795; Sun, 28 Nov 1999 15:06:08 -0800 (PST) Message-Id: <199911282306.PAA24795@implode.root.com> To: Mohit Aron Cc: freebsd-net@FreeBSD.ORG Subject: Re: interaction between Nagle's algorithm and TCP delayed ACKs In-reply-to: Your message of "Sun, 28 Nov 1999 14:27:08 CST." <199911282027.OAA04627@cs.rice.edu> From: David Greenman Reply-To: dg@root.com Date: Sun, 28 Nov 1999 15:06:08 -0800 Sender: owner-freebsd-net@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.org > FreeBSD-2.2.6 had a macro called ACK_HACK in /sys/netinet/tcp_input.c >that was effective in avoiding the undesirable interactions between the >TCP Nagle's algorithm and the delayed ACKs. Basically, if the PUSH flag >on a packet was set, this macro forced TCP to send an acknowledgment >immediately. Since the PUSH flag is usually set on small packets that trigger >Nagle's algorithm, this macro was effective. > >I checked the code for FreeBSD-3.3 and this macro is no longer there in >/sys/netinet/tcp_input.c. Can this feature be re-added in later releases. >In fact, I'd even like it to be turned on by default (it wasn't enabled in >FreeBSD-2.2.6 by default). I was the one who originally added it and then later removed it. I don't recall the reason I removed, except perhaps that I thought it wasn't being used by anyone and was also not something that should be optional. Probably not a bad idea to just make it the standard behavior. -DG David Greenman Co-founder/Principal Architect, The FreeBSD Project - http://www.freebsd.org Creator of high-performance Internet servers - http://www.terasolutions.com Pave the road of life with opportunities. To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-net" in the body of the message