Panzer: convert stk-adapter use of CommAll to CommSparse
Created by: rppawlo
Email from Alan is below. STK is replacing CommAll object with CommSparse object. In the next month or two we will have to switch panzer our use over to the new object.
@trilinos/panzer @eric-c-cyr @jmgate
Roger and/or Eric,
I notice that in Panzer_STK_Interface.cpp you are using the stk CommAll class. The CommAll class has some confusing implementation which may use MPI_Alltoall under certain circumstances, and we’ve concluded that doesn’t scale as well as point-to-point communication. The stk CommSparse class will be replacing the CommAll class. It has an almost-identical API and should perform a little better. In your usage of CommAll, the only change you would need to make is to no longer pass any argument to the allocate_buffers call. With that change you can simply replace the declaration of CommAll with CommSparse, and #include <stk_util/parallel/CommSparse.hpp>
Alan