click perform effects with respect to RAM

[Adam D'Amico]

The cards are Intel Pro/1000T model, 32bit 33/66MHz PCI.  The only
machine we had lying around to play with this on was a Dell Optiplex
workstation.  Certainly not ideal, but......

Adam

On Thu, 2003-02-20 at 05:08, Gordon Lee wrote:
> > A little more info abut the setup, all three NICs are on the same PCI bus,
> > which I believe is of the 33mhz variety.
> 
> 33Mhz slots are typically only 32 bits wide.
> I believe that most if not all e1000 cards are 64 bits wide.
> Do you have a 64 bit wide card sitting in a 32 bit slot ?  
> It would be pretty obvious because the back half of the card 
> edge connector would be suspended outside of the PCI slot.  
> Some makers say they support that, but it can produce undefined 
> behaviour.  Frequent Tx hang/restarts might explain the low rate.
> 
> The system chipset can also make a big difference in performance,
> although these numbers seem too slow to be explained by that alone.
> ServerWorks in particular make a fast chipset.
> 
> > The two outgoing interfaces are
> > connected by a crossover cable because they wouldn't actually transmit
> > packets otherwise.  I don't know if that is relevant at all, but just in
> > case.  I have no other equipment to which I can currently connect those
> > interfaces for the same effect.
> 
> Do you mean that the two ports are simply connected to each other ?
> If not, what exactly are they connected to ?
> 
> Another thing that can slow down rates (again not to this extent alone)
> is the speed/duplex negotiated on the link.  To get more raw information
> on what is happening at the hardware level, try this:
> 
> bash$ cat /proc/net/PRO_LAN_Adapters/eth2.info
>   ...
> bash$ cat /proc/net/PRO_LAN_Adapters/eth3.info
>   ...
> 
> This will print the link speed and duplex, and the PCI bus speed/width,
> among many other things.
> 
> It may be that there is a combination of issues that contribute 
> to the slowdown.
> 
>     - GL