From owner-freebsd-hackers Mon Dec 31 11:27: 3 2001 Delivered-To: freebsd-hackers@freebsd.org Received: from apollo.backplane.com (apollo.backplane.com [216.240.41.2]) by hub.freebsd.org (Postfix) with ESMTP id A94F837B437 for ; Mon, 31 Dec 2001 11:27:01 -0800 (PST) Received: (from dillon@localhost) by apollo.backplane.com (8.11.6/8.9.1) id fBVJR0K21683; Mon, 31 Dec 2001 11:27:00 -0800 (PST) (envelope-from dillon) Date: Mon, 31 Dec 2001 11:27:00 -0800 (PST) From: Matthew Dillon Message-Id: <200112311927.fBVJR0K21683@apollo.backplane.com> To: Terry Lambert Cc: Mike Silbersack , Josef Karthauser , Tomas Svensson , freebsd-hackers@FreeBSD.ORG Subject: Re: FreeBSD performing worse than Linux? References: <200112310704.fBV74Wb18947@apollo.backplane.com> <3C30B31C.FFD2363B@mindspring.com> <200112311902.fBVJ2kk21403@apollo.backplane.com> <3C30BB0C.7061DCCD@mindspring.com> Sender: owner-freebsd-hackers@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.ORG :I'm talking about capping the maximum negotiable window size :over the USB adapter... : :How can this cause problems, since (1) the only thing we are talking :about is window size, not packet size (MTU), and (2) the only thing :it will effect is the TCP stream post negotiation, so it should not :result in a slowdown for any virtual circuit other than those that :*NEED* a slowdown? : :-- Terry If you look at the tcp dump Josef sent, the server was sending 32-byte (data) packets over TCP. It only took 8 packets or so to blow up the USB adapter. 8x32 = 256 bytes. So unless you intend to cap the window size at, say, 128 bytes, this will solve the ssh issue but destroy performance for everything else going over the USB ethernet. -Matt Matthew Dillon To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hackers" in the body of the message