shorten the waiting time on txgen

Signed-off-by: Leo Chen <leo@harmony.one>

cmd/client/txgen/main.go

@@ -123,11 +123,7 @@ func main() {
 	clientNode.Client = client.NewClient(clientNode.GetHost(), shardIDLeaderMap)
 
 	readySignal := make(chan uint32)
-	go func() {
-		for i := range shardIDLeaderMap {
-			readySignal <- i
-		}
-	}()
+
 	// This func is used to update the client's blockchain when new blocks are received from the leaders
 	updateBlocksFunc := func(blocks []*types.Block) {
 		utils.GetLogInstance().Info("[Txgen] Received new block", "block", blocks)
@@ -158,12 +154,18 @@ func main() {
 
 	// Start the client server to listen to leader's message
 	go clientNode.StartServer()
-	// wait for 1 seconds for client to send ping message to leader
-	time.Sleep(time.Second)
 	clientNode.State = node.NodeReadyForConsensus
 
+	go func() {
+		// wait for 3 seconds for client to send ping message to leader
+		// FIXME (leo) the readySignal should be set once we really sent ping message to leader
+		time.Sleep(3 * time.Second) // wait for nodes to be ready
+		for i := range shardIDLeaderMap {
+			readySignal <- i
+		}
+	}()
+
 	// Transaction generation process
-	time.Sleep(5 * time.Second) // wait for nodes to be ready
 	start := time.Now()
 	totalTime := float64(*duration)