1. A method of determining adapter affinity in a high performance computing (HPC) environment of the type including a plurality of distributed computing components defining a plurality of locations and a plurality of input/output (IO) adapters, with each distributed computing component including at least one processing element, and with each IO adapter coupled to a distributed computing component among the plurality of distributed computing components, the method comprising: for each of a plurality of candidate mappings that speculatively map at least one IO adapter to at least one location among the plurality of locations, running a performance test for a task executed by a processing element in a distributed computing component at a first location among the plurality of locations, wherein the plurality of candidate mappings includes first and second candidate mappings, wherein the first candidate mapping maps a first IO adapter among the plurality of IO adapters to the first location, and the second candidate mapping maps a second IO adapter among the plurality of IO adapters to the first location, and wherein running the performance test respectively generates first and second test results for the first and second candidate mappings; and generating speculative adapter affinity information that assigns at least one IO adapter to at least one location among the plurality of locations based upon the performance test run for each of the plurality of candidate mappings, including assigning the first IO adapter to the first location based upon a comparison of the first and second test results for the first and second candidate mappings.