Added a barrier to the DHT performance test for reliability.

Improved buffered exchange performance slightly by ensuring more consistent flushing.

demoapps/rpc/dht_performance_test.cpp

@@ -49,7 +49,7 @@ int main(int argc, char ** argv) {
   std::cout << "I am machine id " << dc.procid() 
             << " in " << dc.numprocs() << " machines"<<std::endl;
   dht<std::string, std::string> testdht(dc);
-
+  dc.barrier();  
   std::vector<std::pair<std::string, std::string> > data;
   const size_t NUMSTRINGS = 10000;
   const size_t strlen[4] = {16, 128, 1024, 10240};

src/graphlab/rpc/buffered_exchange.hpp

@@ -136,6 +136,7 @@ namespace graphlab {
           send_locks[index].unlock();
           // complete the send
           rpc.split_call_end(proc, prevarc);
+          rpc.dc().flush_soon(proc);
         }
       }
     }
@@ -152,6 +153,7 @@ namespace graphlab {
         }
         send_locks[i].unlock();
       }
+      rpc.dc().flush_soon();
       rpc.full_barrier();
     } // end of flush