From owner-freebsd-net Thu Jun 10 7:42:14 1999 Delivered-To: freebsd-net@freebsd.org Received: from sugar.pharlap.com (sugar.pharlap.com [192.107.36.1]) by hub.freebsd.org (Postfix) with ESMTP id 73FC414CA1 for ; Thu, 10 Jun 1999 07:42:11 -0700 (PDT) (envelope-from clark@pharlap.com) Received: from clark ([192.107.36.171]) by sugar.pharlap.com (Post.Office MTA v3.5.2 release 221 ID# 0-56365U200L2S100V35) with SMTP id com for ; Thu, 10 Jun 1999 10:42:09 -0400 From: clark@pharlap.com (Clark Jarvis) Date: Thu, 10 Jun 1999 09:44:32 -0400 To: freebsd-net@FreeBSD.ORG In-Reply-To: Subject: Re: Poor TCP performance between 2.2.5 and 2.2.8 X-Mailer: MR/2 Internet Cruiser Edition for OS/2 v1.60 b60 Message-ID: <19990610144209302.AAA410@sugar.pharlap.com@clark> Sender: owner-freebsd-net@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.org In , on 06/09/99 at 04:49 PM, Bill said: >I continually experience poor TCP performance when sending large files >from my FreeBSD 2.2.5 box (Linksys ISA NIC) to my Windows 95 box (Linksys >PCI NIC). I have an Ethernet hub and I can see the "Collision" light >illuminate nearly steadily ON when transfering a large file from the >FreeBSD box to the Windows box (but not the other way around). >I did post a PR a couple of FreeBSD versions ago, when I first noticed >the problem, and got one of those blanket "must be your hardware" >answers. Since the poor performance is not a big deal in my environment, >I have not pursued a resolution more insistently. But, most definitely, >since about FreeBSD 2.2.3 (give or take a few) I have observed this poor >TCP performance along with the high volume of network collisions when >transfering large files out of the FreeBSD box. This problem was not >evident in the early 2.x releases. Check to see if the Linksys W95/PCI driver (DEC chip? I think) has settings to adjust the early transmit threshold. I fixed a similar problem with Win95 talking to our embedded RTOS by bumping the xmit threshold up from 512 bytes to 1024 bytes. Throughput went up by a factor of 10, almost. Only found the problem by the constant collision lights on the hub. This was over a 100Mb link, but there was a 10Mb setting for this also. I realize this may be way off track, but what-the-hey, it was worth a shot... -- Clark To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-net" in the body of the message