NRT - Fix issue with 1 node jobs. It turns out the network does need to
be setup for 1 node jobs. Here are some of the reasons from IBM... 1. PE expects it. 2. For failover, if there was some challenge or difficulty with the shared-memory method of data transfer, the protocol stack might want to go through the adapter instead. 3. For flexibility, the protocol stack might want to be able to transfer data using some variable combination of shared memory and adapter-based communication, and 4. Possibly most important, for overall performance, it might be that bandwidth or efficiency (BW per CPU cycles) might be better using the adapter resources. (An obvious case is for large messages, it might require a lot fewer CPU cycles to program the DMA engines on the adapter to move data between tasks, rather than depend on the CPU to move the data with loads and stores, or page re-mapping -- and a DMA engine might actually move the data more quickly, if it's well integrated with the memory system, as it is in the P775 case.)
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