Wait until all rpcs are done instead of a hard stop.

stress/client/main.go

@@ -225,8 +225,6 @@ func performRPCs(gauge *gauge, conn *grpc.ClientConn, selector *weightedRandomTe
 	var numCalls int64
 	startTime := time.Now()
 	for {
-		done := make(chan bool, 1)
-		go func() {
 		test := selector.getNextTest()
 		switch test {
 		case "empty_unary":
@@ -252,14 +250,13 @@ func performRPCs(gauge *gauge, conn *grpc.ClientConn, selector *weightedRandomTe
 		case "custom_metadata":
 			interop.DoCustomMetadata(client, grpc.FailFast(false))
 		}
-			done <- true
-		}()
+		numCalls++
+		gauge.set(int64(float64(numCalls) / time.Since(startTime).Seconds()))
+
 		select {
 		case <-stop:
 			return
-		case <-done:
-			numCalls++
-			gauge.set(int64(float64(numCalls) / time.Since(startTime).Seconds()))
+		default:
 		}
 	}
 }