Hello,
I am configuring one Linux Cluster - 16xP4HT 2.8 + 1x2Xeon HT 2.8 with
Suse 8.2 and Lam 656. Lam testsuite is running OK. When i am testing
some lam c programs, then the cpu usage an all nodes is about 60% and
when i am doing some LSDyna tests, than it is much worse - cpu usage is
only 3-7%. The same programm is running faster on one host ...
All nodes have Intel Boards D875PBZ with e1000 onboard are connected
with GB Eth using a very good Cisco 24xGB Eth . I am thinking that this
low cpu usage is caused by low network performance, but i was already
playing with different MTU, RxIntDelay,TxIntDelay,wmem_max and rmem_max,
there is no significant change, and average answer time between nodes
(ping -f -s 64000 host) is ~1.5ms, so it about 80 MB/sec, probably the
possible maximum.
Any ideas are welcome. You can mail me directly
:) Tomek
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