@Override
  public Execution onMembers(DistributedSystem system, Set<DistributedMember> distributedMembers) {
    if (system == null) {
      throw new FunctionException(String.format("%s passed is null",
          "DistributedSystem instance "));
    }
    if (distributedMembers == null) {
      throw new FunctionException(String.format("%s passed is null",
          "distributedMembers set "));
    }
    return new MemberFunctionExecutor(system, distributedMembers);
  }
use when the optimization to execute onMember locally is not desired.
geode-core/src/main/java/org/apache/geode/internal/cache/execute/InternalFunctionExecutionServiceImpl.java