[openib-general] Question about the IPoIB bandwidth performance ?

[Talpey, Thomas]

Thanks Parks, this is a very interesting perspective.
I will avoid going into my rant about edge devices for
now, however. :-)

I am not sure what you mean about using SDP "end to end".
I assume you would perhaps use SDP to these edge nodes,
but this would require terminating the SDP connection and
re-issuing the stream over TCP to the Panasas box, wouldn't it?

Would this bridging be done in-kernel, like your IPoIB/Ethernet
solution today, or would you implement a daemon? It will be
a difficult challenge, I predict.

Tom.

At 02:16 PM 6/5/2006, Parks Fields wrote:
>
>>
>>I consider IPoIB to be Ethernet emulation.
>>
>>As for apples and oranges, my point exactly.
>
>
>It is not really about comparisons. Here at LANL we have an 
>environment where all our new Clusters have to mount our global 
>parallel file system Panasas. It is ethernet and will be for a while.
>
>Cluster interconnect is IB and the compute nodes do NOT have 
>ethernet, so we created i-o nodes to "bridge " IB to ethernet.
>
>Compute node----IB---i/o node---10gig---ethernet switch ----  panasas
>
>We like to match / balance the network to bandwidth to storage 
>bandwidth plus try to achieve 1GB/sec per TF of the machine.  EX: 
>50TF machine  = 50 GB/sec of storage bandwidth needed.
>
>So if IPoIB would give us ~700 MB/sec and came out the other side 
>with 10gigE at ~800 that would be nice.
>Hope this helps.   We are now trying to find out is SDP will work end-to-end.
>
>thanks
>parks
>
>
>
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