Very high latency....

[Anirudh Modi]

Hi,

	I have recently set up a 25 node dual PII-400 cluster for our
research group here in our University. I am having a few problems with my
MPI codes. After testing some MPI codes, I found out that my network
latency was too high (4.5 ms) for message sizes under 128 bytes, although
I am getting transfer rates upto 11.24 MB/sec for large message sizes
between every nodes (I am running at 100 Mb w/Full duplex on)! I am using
v0.99G of the 3c59x driver and have a 3com 3c905B Cyclone card on every
node. Could this be a possible driver problem ? Please help. I am running
RedHat 5.1 with 2.0.35 #10 kernel (the newer 2.1.128 and 2.0.36 kernels
refuse to detect both my ethernet cards on the server properly and hence
I have been unable to use them).

Also, I am having problems with 2 ethernet cards (both of them 3c905B
Cyclone) on my server with 0.99G driver, so I had to resort to the older
0.99E driver which works fine. The 0.99G driver wasn't autodetecting both
cards at full duplex and I do not know how to force it (as I am using all
these drivers built into the kernel and not as modules). Any help will
be highly appreciated. Thanx in advance.

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     |              A N I R U D H    M O D I                 |     
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