diff --git a/blockbook.go b/blockbook.go
index 7f70cbe4..4eecef01 100644
--- a/blockbook.go
+++ b/blockbook.go
@@ -51,7 +51,7 @@ var (
 	prof        = flag.String("prof", "", "http server binding [address]:port of the interface to profiling data /debug/pprof/ (default no profiling)")
 
 	syncChunk   = flag.Int("chunk", 100, "block chunk size for processing")
-	syncWorkers = flag.Int("workers", 8, "number of workers to process blocks")
+	syncWorkers = flag.Int("workers", 8, "number of workers to process blocks (default 8)")
 	dryRun      = flag.Bool("dryrun", false, "do not index blocks, only download")
 
 	httpServerBinding = flag.String("httpserver", "", "http server binding [address]:port, (default no http server)")
diff --git a/db/sync.go b/db/sync.go
index fb681bd4..7f25a56a 100644
--- a/db/sync.go
+++ b/db/sync.go
@@ -187,6 +187,7 @@ func (w *SyncWorker) connectBlocks(onNewBlock func(hash string)) error {
 	return nil
 }
 
+// ConnectBlocksParallel uses parallel goroutines to get data from blockchain daemon
 func (w *SyncWorker) ConnectBlocksParallel(lower, higher uint32) error {
 	type hashHeight struct {
 		hash   string
@@ -200,21 +201,24 @@ func (w *SyncWorker) ConnectBlocksParallel(lower, higher uint32) error {
 	hchClosed.Store(false)
 	var getBlockMux sync.Mutex
 	getBlockCond := sync.NewCond(&getBlockMux)
-	totalWaitDuration := time.Duration(0)
-	lastConnectedBlock := int(lower) - 1
+	lastConnectedBlock := lower - 1
 	writeBlockDone := make(chan struct{})
-	writeBlock := func() {
+	writeBlockWorker := func() {
 		defer close(writeBlockDone)
+		lastBlock := lower - 1
 		for b := range bch {
-			// glog.Info("WriteBlock ", b.Height)
-			err = w.db.ConnectBlock(b)
-			if err != nil {
-				glog.Error("WriteBlock worker ", b.Height, " ", b.Hash, " error ", err)
+			if lastBlock+1 != b.Height {
+				glog.Error("writeBlockWorker skipped block, last connected block", lastBlock, ", new block ", b.Height)
 			}
+			err := w.db.ConnectBlock(b)
+			if err != nil {
+				glog.Error("writeBlockWorker ", b.Height, " ", b.Hash, " error ", err)
+			}
+			lastBlock = b.Height
 		}
 		glog.Info("WriteBlock exiting...")
 	}
-	getBlock := func(i int) {
+	getBlockWorker := func(i int) {
 		defer wg.Done()
 		var err error
 		var block *bchain.Block
@@ -224,10 +228,10 @@ func (w *SyncWorker) ConnectBlocksParallel(lower, higher uint32) error {
 				if err != nil {
 					// signal came while looping in the error loop
 					if hchClosed.Load() == true {
-						glog.Error("Worker ", i, " connect block error ", err, ". Exiting...")
+						glog.Error("getBlockWorker ", i, " connect block error ", err, ". Exiting...")
 						return
 					}
-					glog.Error("Worker ", i, " connect block error ", err, ". Retrying...")
+					glog.Error("getBlockWorker ", i, " connect block error ", err, ". Retrying...")
 					w.metrics.IndexResyncErrors.With(common.Labels{"error": err.Error()}).Inc()
 					time.Sleep(time.Millisecond * 500)
 				} else {
@@ -237,34 +241,32 @@ func (w *SyncWorker) ConnectBlocksParallel(lower, higher uint32) error {
 			if w.dryRun {
 				continue
 			}
-			start := time.Now()
 			getBlockMux.Lock()
 			for {
-				if uint32(lastConnectedBlock+1) == hh.height {
-					lastConnectedBlock = int(hh.height)
-					// get data to writeBlock routine
-					// glog.Info("Worker ", i, " have block ", hh.height, ". Sending.")
+				// we must make sure that the blocks are written to db in the correct order
+				if lastConnectedBlock+1 == hh.height {
+					// we have the right block, pass it to the writeBlockWorker
+					lastConnectedBlock = hh.height
 					bch <- block
-					totalWaitDuration += time.Since(start)
 					getBlockCond.Broadcast()
-					getBlockMux.Unlock()
 					break
 				}
-				// glog.Info("Worker ", i, " have block ", hh.height, ". Waiting.")
-				getBlockCond.Wait()
+				// break the endless loop on OS signal
 				if hchClosed.Load() == true {
 					break
 				}
+				// wait for the time this block is top be passed to the writeBlockWorker
+				getBlockCond.Wait()
 			}
+			getBlockMux.Unlock()
 		}
-		glog.Info("Worker ", i, " exiting...")
+		glog.Info("getBlockWorker ", i, " exiting...")
 	}
 	for i := 0; i < w.syncWorkers; i++ {
 		wg.Add(1)
-		go getBlock(i)
+		go getBlockWorker(i)
 	}
-	go writeBlock()
-
+	go writeBlockWorker()
 	var hash string
 ConnectLoop:
 	for h := lower; h <= higher; {
@@ -282,16 +284,20 @@ ConnectLoop:
 			}
 			hch <- hashHeight{hash, h}
 			if h > 0 && h%1000 == 0 {
-				glog.Info("connecting block ", h, " ", hash, " wait for writeBlock ", totalWaitDuration)
+				glog.Info("connecting block ", h, " ", hash)
 			}
 			h++
 		}
 	}
 	close(hch)
-	// signal stop to workers that are in w.chain.GetBlockWithoutHeader error loop
+	// signal stop to workers that are in a loop
 	hchClosed.Store(true)
-	// first wait for the getBlock routines to finish and then close bch channel
-	getBlockCond.Broadcast()
+	// broadcast syncWorkers times to unstuck all waiting getBlockWorkers
+	for i := 0; i < w.syncWorkers; i++ {
+		getBlockCond.Broadcast()
+	}
+	// first wait for the getBlockWorkers to finish and then close bch channel
+	// so that the getBlockWorkers do not write to the closed channel
 	wg.Wait()
 	close(bch)
 	<-writeBlockDone