channel bonding rtl8139 works??

Eric Kuhnke eric at
Wed Sep 5 04:34:38 PDT 2001

In my experience, the Realtek 8139 is the worst modern network controller
on the planet.  It's the cheapest available, and commonly found on $65
generic (ie: PC Chips) celeron motherboards.  Sometimes it completely
refuses to autodetect speed and duplex of a connection.  You really do get
what you pay for...

I second Robert's comment on the 3C905C-TX NIC, which is an excellent
card.  They can be had for under $30 if you look around.  The Intel 82559
is also good, as evidenced by its use in high end Supermicro Serverworks
III-HE chipset motherboards.

Eric Kuhnke
Lead Engineer / Operations Manager
Fnord Datacenter Systems Inc.
eric at
voice: +1-360-527-3301 fax: +1-360-647-0752

-----Original Message-----
From: beowulf-admin at [mailto:beowulf-admin at]On
Behalf Of Robert G. Brown
Sent: Wednesday, September 05, 2001 3:39 AM
To: << Dragon >>
Cc: beowulf at
Subject: Re: channel bonding rtl8139 works??

On Mon, 3 Sep 2001, <<   Dragon  >> wrote:

>   Hi, does any body know if the RTL-8139 kernel module for the KNE120TX
> works with channel bonding??
>  I channel bonded 3 KNE120tx cards on 2 computers (3 cards per system)
> the comunication between them is very slow, I don't know if the problem
> in the rtl8139 kernel module (Red Hat 6.2)

I don't know about channel bonding per se, but the RTL8139 NIC is Dark
Evil.  In my opinion, of course: YMMV, caveat emptor, I may be crazy
(some would say there is little doubt:-), standard disclaimers etc.

Still, my own experience:  It is one of the few cards with which I can
still consistently crash a linux box currently in my possesion when I
whack it with a very heavy packet stream.  I should note in saying this
that this is with the current RH 7.1 kernel with its "stolen" 8139too
driver, not Don's, although many kernel revisions ago I managed to crash
boxes with two RTL8139's with Don's driver as well.

You should connect to the scyld website and visit the rtl8139 page and
read the notes there.  I'd have to say that even if your particular
implementation of the 8139 is more stable than my own (maybe Kingston
did a better job of engineering the NICs than my no-name mfr, or maybe
you're using Don's driver already and it actually works stably where the
8139too dies) it is a relatively poor choice for a beowulf NIC.  Even
when I run just one card at a time (and cannot crash the system) the
card seems to choke up under a heavy packet load and actually slow down
to a crawl.

Crush.  Kill.  Destroy.  Choose another card.

They are more expensive, but 3c905's do PXE and WOL and can save you the
cost of a floppy or CD-ROM (per node) for the original install.  They
have MUCH better latency and bw numbers in my tests -- better than even
midrange cards that DON'T really suck (e.g. PNIC based cards).


>  Does any body know which kernel module can I use for the KNE120TX that
> will support channel bonding??
>  I have a cluster bonded with KNE100TX cards using the Tulip kernel
> and they work fine.
>  Any help is appreciated.
>  Thanks.
>    Raul A. Gonzalez Olimon
>    al303917 at
>    Universidad Autonoma de Baja California
>    Mexico.
> _______________________________________________
> Beowulf mailing list, Beowulf at
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Robert G. Brown	             
Duke University Dept. of Physics, Box 90305
Durham, N.C. 27708-0305
Phone: 1-919-660-2567  Fax: 919-660-2525     email:rgb at

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