Dell 1600SC + 82540EM poor performance..HELP NEEDED

Jeff Layton jeffrey.b.layton at
Thu Jul 24 08:04:20 EDT 2003


   What kind of switch (100 or 1000)? Have you looked
at the switch ports? Are they connecting at full or half
duplex? How about the NICs? You'll see bad performance
with a duplex mismatch between the NICs and switch.
Are you forcing the NICs or are they auto-negiotiating?

Good Luck!


> Hello,
> We have recently received 48 Bi-xeon Dell 1600SC and we are performing 
> some benchmarks to tests the cluster.
> Unfortunately we have very bad perfomance with the internal gigabit 
> card (82540EM chipset). We have passed linux netperf test and we have 
> only 33 Mo
> between 2 machines. We have changed the drivers for the last ones, 
> installed procfgd and so on... Finally we had Win2000 installed and 
> the last driver
> from intel installed : the results are identical... To go further we 
> have installed a PCI-X 82540EM card and re-run the tests : in that way the
> results are much better : 66 Mo full duplex...
> So the question is : is there a well known problem with this DELL 
> 1600SC concernig the 82540EM integration on the motherboard ????
> As anyone already have (heard about) this problem ?
> Is there any solution ?
> thx for your help

Dr. Jeff Layton
Chart Monkey - Aerodynamics and CFD
Lockheed-Martin Aeronautical Company - Marietta

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