app/vminsert: moves replication at datapointWrite level

* It allows to tolerate slow storage node for replicationFactor > 1 and disableRerouting=false
* It allows to have partial replication with replicationFactor > and dropSamplesOnOverload=true
* It increases cpu and memory usage by 30-50% per replica

Signed-off-by: f41gh7 <nik@victoriametrics.com>

app/vminsert/netstorage/insert_ctx.go

@@ -122,11 +122,48 @@ func (ctx *InsertCtx) ApplyRelabeling() {
 func (ctx *InsertCtx) WriteDataPoint(at *auth.Token, labels []prompb.Label, timestamp int64, value float64) error {
 	ctx.MetricNameBuf = storage.MarshalMetricNameRaw(ctx.MetricNameBuf[:0], at.AccountID, at.ProjectID, labels)
 	storageNodeIdx := ctx.GetStorageNodeIdx(at, labels)
-	return ctx.WriteDataPointExt(storageNodeIdx, ctx.MetricNameBuf, timestamp, value)
+	return ctx.writeDataPointToReplicas(storageNodeIdx, ctx.MetricNameBuf, timestamp, value)
 }
 
 // WriteDataPointExt writes the given metricNameRaw with (timestmap, value) to ctx buffer with the given storageNodeIdx.
 func (ctx *InsertCtx) WriteDataPointExt(storageNodeIdx int, metricNameRaw []byte, timestamp int64, value float64) error {
+	return ctx.writeDataPointToReplicas(storageNodeIdx, metricNameRaw, timestamp, value)
+}
+
+func (ctx *InsertCtx) writeDataPointToReplicas(storageNodeIdx int, metricNameRaw []byte, timestamp int64, value float64) error {
+	var firstErr error
+	var failsCount int
+	for i := 0; i < replicas; i++ {
+		snIdx := storageNodeIdx + i
+		if snIdx >= len(ctx.snb.sns) {
+			snIdx %= len(ctx.snb.sns)
+		}
+
+		if err := ctx.writeDataPointExt(snIdx, metricNameRaw, timestamp, value); err != nil {
+			if replicas == 1 {
+				return fmt.Errorf("cannot write datapoint: %w", err)
+			}
+			if firstErr == nil {
+				firstErr = err
+			}
+			failsCount++
+			// The data is partially replicated, so just emit a warning and return true.
+			// We could retry sending the data again, but this may result in uncontrolled duplicate data.
+			// So it is better returning true.
+			br := &ctx.bufRowss[snIdx]
+			rowsIncompletelyReplicatedTotal.Add(br.rows)
+			incompleteReplicationLogger.Warnf("cannot make a copy #%d out of %d copies according to -replicationFactor=%d, used_nodes=%d for %d bytes with %d rows, "+
+				"since a part of storage nodes is temporarily unavailable", i+1, replicas, *replicationFactor, len(br.buf), br.rows)
+			continue
+		}
+	}
+	if failsCount == replicas {
+		return fmt.Errorf("cannot write datapoint to any replicas: %w", firstErr)
+	}
+	return nil
+}
+
+func (ctx *InsertCtx) writeDataPointExt(storageNodeIdx int, metricNameRaw []byte, timestamp int64, value float64) error {
 	br := &ctx.bufRowss[storageNodeIdx]
 	snb := ctx.snb
 	sn := snb.sns[storageNodeIdx]

app/vminsert/netstorage/netstorage.go

@@ -45,6 +45,8 @@ var (
 		"See also -disableRerouting")
 )
 
+var replicas int
+
 var errStorageReadOnly = errors.New("storage node is read only")
 
 func (sn *storageNode) isReady() bool {
@@ -140,15 +142,6 @@ again:
 }
 
 func (sn *storageNode) run(snb *storageNodesBucket, snIdx int) {
-	replicas := *replicationFactor
-	if replicas <= 0 {
-		replicas = 1
-	}
-	sns := snb.sns
-	if replicas > len(sns) {
-		replicas = len(sns)
-	}
-
 	sn.readOnlyCheckerWG.Add(1)
 	go func() {
 		defer sn.readOnlyCheckerWG.Done()
@@ -193,7 +186,7 @@ func (sn *storageNode) run(snb *storageNodesBucket, snIdx int) {
 			continue
 		}
 		// Send br to replicas storage nodes starting from snIdx.
-		for !sendBufToReplicasNonblocking(snb, &br, snIdx, replicas) {
+		for !sendBufToSnNonblocking(snb, &br, snIdx) {
 			d := timeutil.AddJitterToDuration(time.Millisecond * 200)
 			t := timerpool.Get(d)
 			select {
@@ -206,50 +199,38 @@ func (sn *storageNode) run(snb *storageNodesBucket, snIdx int) {
 				sn.checkHealth()
 			}
 		}
+		if sn.isBufferFull.CompareAndSwap(true, false) {
+			logger.Infof("transited node=%s to non-full", sn.dialer.Addr())
+		}
+
 		br.reset()
 	}
 }
 
-func sendBufToReplicasNonblocking(snb *storageNodesBucket, br *bufRows, snIdx, replicas int) bool {
-	usedStorageNodes := make(map[*storageNode]struct{}, replicas)
+func sendBufToSnNonblocking(snb *storageNodesBucket, br *bufRows, snIdx int) bool {
 	sns := snb.sns
-	for i := 0; i < replicas; i++ {
-		idx := snIdx + i
-		attempts := 0
-		for {
-			attempts++
-			if attempts > len(sns) {
-				if i == 0 {
-					// The data wasn't replicated at all.
-					cannotReplicateLogger.Warnf("cannot push %d bytes with %d rows to storage nodes, since all the nodes are temporarily unavailable; "+
-						"re-trying to send the data soon", len(br.buf), br.rows)
-					return false
-				}
-				// The data is partially replicated, so just emit a warning and return true.
-				// We could retry sending the data again, but this may result in uncontrolled duplicate data.
-				// So it is better returning true.
-				rowsIncompletelyReplicatedTotal.Add(br.rows)
-				incompleteReplicationLogger.Warnf("cannot make a copy #%d out of %d copies according to -replicationFactor=%d for %d bytes with %d rows, "+
-					"since a part of storage nodes is temporarily unavailable", i+1, replicas, *replicationFactor, len(br.buf), br.rows)
-				return true
-			}
-			if idx >= len(sns) {
-				idx %= len(sns)
-			}
-			sn := sns[idx]
-			idx++
-			if _, ok := usedStorageNodes[sn]; ok {
-				// The br has been already replicated to sn. Skip it.
-				continue
-			}
-			if !sn.sendBufRowsNonblocking(br) {
-				// Cannot send data to sn. Go to the next sn.
-				continue
-			}
-			// Successfully sent data to sn.
-			usedStorageNodes[sn] = struct{}{}
-			break
+	idx := snIdx
+	attempts := 0
+	for {
+		attempts++
+		if attempts > len(sns) {
+			// The data wasn't replicated at all.
+			cannotReplicateLogger.Warnf("cannot push %d bytes with %d rows to storage nodes, since all the nodes are temporarily unavailable; "+
+				"re-trying to send the data soon", len(br.buf), br.rows)
+			return false
 		}
+		if idx >= len(sns) {
+			idx %= len(sns)
+		}
+		sn := sns[idx]
+		idx++
+
+		if !sn.sendBufRowsNonblocking(br) {
+			// Cannot send data to sn. Go to the next sn.
+			continue
+		}
+		// Successfully sent data to sn.
+		break
 	}
 	return true
 }
@@ -413,6 +394,8 @@ type storageNode struct {
 	// In this case the data is re-routed to the remaining healthy vmstorage nodes.
 	isBroken atomic.Bool
 
+	isBufferFull atomic.Bool
+
 	// isReadOnly is set to true if the given vmstorage node is read only
 	// In this case the data is re-routed to the remaining healthy vmstorage nodes.
 	isReadOnly atomic.Bool
@@ -505,6 +488,13 @@ func setStorageNodesBucket(snb *storageNodesBucket) {
 //
 // Call MustStop when the initialized vmstorage connections are no longer needed.
 func Init(addrs []string, hashSeed uint64) {
+	replicas = *replicationFactor
+	if replicas <= 0 {
+		replicas = 1
+	}
+	if replicas > len(addrs) {
+		replicas = len(addrs)
+	}
 	snb := initStorageNodes(addrs, hashSeed)
 	setStorageNodesBucket(snb)
 }
@@ -772,7 +762,7 @@ var noStorageNodesLogger = logger.WithThrottler("storageNodesUnavailable", 5*tim
 func getNotReadyStorageNodeIdxs(snb *storageNodesBucket, dst []int, snExtra *storageNode) []int {
 	dst = dst[:0]
 	for i, sn := range snb.sns {
-		if sn == snExtra || !sn.isReady() {
+		if sn == snExtra || !sn.isReady() || sn.isBufferFull.Load() {
 			dst = append(dst, i)
 		}
 	}
@@ -787,10 +777,17 @@ func (sn *storageNode) trySendBuf(buf []byte, rows int) bool {
 
 	sent := false
 	sn.brLock.Lock()
-	if sn.isReady() && len(sn.br.buf)+len(buf) <= maxBufSizePerStorageNode {
+	if !sn.isReady() {
+		return sent
+	}
+	if len(sn.br.buf)+len(buf) <= maxBufSizePerStorageNode {
 		sn.br.buf = append(sn.br.buf, buf...)
 		sn.br.rows += rows
 		sent = true
+	} else {
+		if sn.isBufferFull.CompareAndSwap(false, true) {
+			logger.Infof("node: %s transited to full", sn.dialer.Addr())
+		}
 	}
 	sn.brLock.Unlock()
 	return sent