From owner-freebsd-hackers Sun Dec 30 23: 5:19 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 7FEDA37B41F for ; Sun, 30 Dec 2001 23:05:17 -0800 (PST) Received: (from dillon@localhost) by apollo.backplane.com (8.11.6/8.9.1) id fBV74Wb18947; Sun, 30 Dec 2001 23:04:32 -0800 (PST) (envelope-from dillon) Date: Sun, 30 Dec 2001 23:04:32 -0800 (PST) From: Matthew Dillon Message-Id: <200112310704.fBV74Wb18947@apollo.backplane.com> To: Mike Silbersack Cc: Josef Karthauser , Tomas Svensson , Subject: Re: FreeBSD performing worse than Linux? References: 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 going to blame the USB ethernet driver for dropping packets; Thomas :Zenker has been reporting similar problems on -net. He says that he did :not have problems with packet loss with 4.3, but has not been able to :track down what changed. Maybe you could compare notes with him and see :what you can come up with. : :Mike "Silby" Silbersack new-reno was artifically limiting the max number of in-transit packets to 4. This is probably why the USB ethernet worked with 4.3, but it destroyed TCP performance for everything else and was removed. I don't think there is kernel solution to the USB problems, short of fixing the driver (if that's even possible). The packets are being sent from the server and the only thing the client has control over is the receive window advertisement. You could artifically reduce the window advertisement on the client to deal with lots of small packets but it would destroy performance for larger packets / data streams. -Matt Matthew Dillon To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hackers" in the body of the message