From nobody  Mon Mar  3 06:43:06 1997
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Date: Mon, 3 Mar 1997 06:43:06 -0800 (PST)
From: rtm@eecs.harvard.edu
To: freebsd-gnats-submit@freebsd.org
Subject: DE500 board exhibits capture effect
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>Number:         2857
>Category:       kern
>Synopsis:       DE500 board exhibits capture effect
>Confidential:   no
>Severity:       non-critical
>Priority:       low
>Responsible:    freebsd-bugs
>State:          closed
>Quarter:        
>Keywords:       
>Date-Required:  
>Class:          sw-bug
>Submitter-Id:   current-users
>Arrival-Date:   Mon Mar  3 06:50:01 PST 1997
>Closed-Date:    Tue May 9 13:37:07 PDT 2000
>Last-Modified:  Tue May 09 13:38:12 PDT 2000
>Originator:     Robert Morris
>Release:        2.1.5
>Organization:
Harvard University
>Environment:
FreeBSD punish.uun.org 2.1.5-RELEASE FreeBSD 2.1.5-RELEASE #0: Tue Feb  4 16:42:28 EST 1997     rtm@punish.uun.org:/usr/src/sys/compile/PUNISH  i386

>Description:
I have some DE500 boards running at 10 megabits with FreeBSD 2.1.5.  I
believe I've run into the problem that the 21x40 capture effect
resolution was meant to solve: if one host is doing a long file
transfer, other hosts drop outgoing packets due to excessive
re-transmits. When I turn on CAPTREFFCT and ENHCAPTEFFCT in if_de.c,
the problem goes away (for one greedy host, anyway; multiple greedy
hosts still cause problems).

FreeBSD says this about my cards:
de0 <Digital DC21140 Fast Ethernet> rev 18 int a irq 10 on pci0:12
de0: Digital DE500 DC21140 [10-100Mb/s] pass 1.2 Ethernet address 00:00:f8:02:36
:c5

>How-To-Repeat:
Transfer a file between two DE500 hosts at 10 megabits.
Ping between two other hosts on the same net.
Observe ping times of tens or hundreds of milliseconds
rather than the expected 1 or 2.
>Fix:
Turn on TULIP_CMD_CAPTREFFCT and TULIP_CMD_ENHCAPTEFFCT in
tulip_dc21140_de500_media_select in if_de.c. I have done this
and observed no ill effects. I have not tried this with
other boards or at 100 megabits.
>Release-Note:
>Audit-Trail:
State-Changed-From-To: open->feedback 
State-Changed-By: wilko 
State-Changed-When: Thu Apr 20 12:44:02 PDT 2000 
State-Changed-Why:  
Have you ever tried using the 'dc' driver that is part of 4.0R and later 
on the DE500s you have (well, maybe had, considering the time the PR 
has been open)? 

Wilko 
State-Changed-From-To: feedback->closed 
State-Changed-By: wilko 
State-Changed-When: Tue May 9 13:37:07 PDT 2000 
State-Changed-Why:  
Assuming problem fixed in a recent release. If not assume  
a new PR will be filed. No response since April 20, 2000 
>Unformatted:
