Frank van der Linden writes:
> On Thu, Jul 30, 1998 at 12:42:11PM +0200, Manuel Bouyer wrote:
> > On Thu, Jul 30, 1998 at 11:36:43AM +0200, Geir.I.Jensen@Runit.Sintef.No wrote:
> > > of handling that speed. However, the network performance I observe is
> > > ridiculous. ftp transfer rates to another directly connected 100Mb
> > > machine gives me just around 40KB/s throughput. This number is
> > > consistent with other tests I have done (like scp, etc).
> > > 
> > 
> > The 3com boards are known to not work well under NetBSD, because
> > the driver doesn't use DMA.
> 
> ..however, 40KB/s is very slow, and it is unlikely to be be caused by that.
> I have seen the maximum performance go from ~10MB/s down to ~6MB/s because
> of a suboptimal driver, but 40KB/s..
> 
> - Frank

This is a problem with the stupid 3c905.  It doesn't properly do NWAY
autonegotiation.  What ends up happening is the Cisco switch thinks you're
running at 100Mb full-duplex, when the 3c905 is actually talking at 10Mb.
If you force the Cisco port to 10Mb half-duplex, your performance should 
jump to ~1MB/sec.  Do not let the output of 'ifconfig -m ep0' confuse you,
the ep driver is not selecting 100Base-TX media, it is using the card how
it is.  Or possibly even setting the card to 10Mb, *after* it has 
successfully done NWAY.  We see this problem frequently with older drivers.
It happens on Netware 4.11, and Win95 clients for sure, possibly on NT.

In general, I would avoid the 3com cards, and go with something based on
the DEC 21140 (and newer) family.  The Bay Networks "NetGear" cards are
quite cheap, and should work fine with your switch.  I force all of my
'de' cards to 100Mb full-duplex, and configure the switch port.  I don't
like the idea of my machine "quietly" falling back to 10Mb.  I might
add a second card for redundancy though.. :-)

-Andrew
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Andrew Gillham                            | This space left blank
gillham@whirlpool.com                     | inadvertently.
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