[eepro100] Re: Problem on Intel Pro/100 751767-004 adapter

Donald Becker becker@scyld.com
Thu, 25 Oct 2001 09:38:20 -0400 (EDT)


On Thu, 25 Oct 2001 thhsieh@linux.org.tw wrote:

> : > However, we suddently found
> : > that its performance behaves very strange. For example, if we use
> : > ftp to transfer a file with size 50MB in the full duplex mode, we found
> : > that to get such a file the transfering rate is only around 36-40 KB/s,
> : > and to send such a file the transfering rate is around 8300 KB/s.
> : 
> : Typical duplex mismatch.
> : 
> : > If we tune off the full duplex mode, both to get and send the file have
> : 
> : Why were you forcing full duplex?
> 
> Because we are setting up a cluster to do the parallel computing.

Forcing full duplex is only reasonable on fiber links.
You should always use autonegotiation with modern equipment.

> : Check for errors in /proc/net/dev.
> 
> Seems no error here. In forced full duplex mode, after getting and
> sending a 50MB file, the result is
> 
> Inter-|   Receive                                                
>  face |bytes    packets errs drop fifo frame compressed multicast
>     lo:     420       6    0    0    0     0          0         0
>   eth0:53900558   53746    0    0    0 13905          0         0

This is the typical error pattern when you have incorrectly forced full
duplex on this end of the link.

You your link partner has forced full duplex, you will get out-of-window
errors on transmit.

> : Why are you forcing the speed and duplex?  The driver works best with
> : the default setting -- autonegotation.
> 
> OK, I tested with the default mode (without applying any options):
> 
> eepro100.c:v1.09j-t 9/29/99 Donald Becker http://cesdis.gsfc.nasa.gov/linux/drivers/eepro100.html
> eepro100.c: $Revision: 1.36 $ 2000/11/17 Modified by Andrey V. Savochkin <saw@saw.sw.com.sg> and others

Note that this driver has split from the driver I support.

> The result is the same: getting files with speed only 33.7 KB/s, and sending
> files with speed 8318.0 KB/s. The /proc/net/dev is:

I see that there are no errors reported on this end of the link.
What about the link partner?

> Although I could just use this driver without boring you. But I think
> that it is cool if we could improve the native driver in Linux kernel
> to work as good as the driver provided by the vander. :-)))

Please try my driver
   http://www.scyld.com/network/eepro100.html
      ftp://www.scyld.com/pub/network/eepro100.c

Donald Becker				becker@scyld.com
Scyld Computing Corporation		http://www.scyld.com
410 Severn Ave. Suite 210		Second Generation Beowulf Clusters
Annapolis MD 21403			410-990-9993