[ofa-general] Re: IPoIB CM mode throughput

[Michael S. Tsirkin]

> Quoting Shirley Ma <xma at us.ibm.com>:
> Subject: IPoIB CM mode throughput
> 
> Hello Michael,
> 
> In one of your email, you mentioned that IPoIB-CM 800MB/s or more throughput
> you got is on a Mellanox 4x back-to-back DDR system. I assume that you get the
> high performance for PCIe bus not PCI_X? Is that right?

I haven't tested PCI-X for performance yet.
But I do expect it to give performance similiar to PCI-Ex:
the system is CPU-bound, not bus-BW bound.

One thing to note: since PCI-X has higher latency than PCI-E, you might need
to tweak TCP window sizes to get good performance with TCP.
Same applies to DDR/SDR.

-- 
MST