snapshot of https://github.com/livekit/livekit.git @ 08c5433449c106943231037d0b892895f6e92d3b (2026-09-15)

pkg/routing/nodestats.go

@@ -0,0 +1,91 @@
+// Copyright 2023 LiveKit, Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package routing
+
+import (
+	"sync"
+	"time"
+
+	"github.com/livekit/protocol/livekit"
+	"github.com/livekit/protocol/logger"
+	"github.com/livekit/protocol/utils"
+
+	"github.com/livekit/livekit-server/pkg/config"
+	"github.com/livekit/livekit-server/pkg/telemetry/prometheus"
+)
+
+type NodeStats struct {
+	config    config.NodeStatsConfig
+	startedAt int64
+
+	lock                 sync.RWMutex
+	statsHistory         []*livekit.NodeStats
+	statsHistoryWritePtr int
+}
+
+func NewNodeStats(conf *config.NodeStatsConfig, startedAt int64) *NodeStats {
+	n := &NodeStats{
+		startedAt: startedAt,
+	}
+	n.UpdateConfig(conf)
+	return n
+}
+
+func (n *NodeStats) UpdateConfig(conf *config.NodeStatsConfig) {
+	n.lock.Lock()
+	defer n.lock.Unlock()
+
+	if conf == nil {
+		conf = &config.DefaultNodeStatsConfig
+	}
+	n.config = *conf
+
+	// set up stats history to be able to measure different rate windows
+	var maxInterval time.Duration
+	for _, rateInterval := range conf.StatsRateMeasurementIntervals {
+		if rateInterval > maxInterval {
+			maxInterval = rateInterval
+		}
+	}
+	n.statsHistory = make([]*livekit.NodeStats, (maxInterval+conf.StatsUpdateInterval-1)/conf.StatsUpdateInterval)
+	n.statsHistoryWritePtr = 0
+}
+
+func (n *NodeStats) UpdateAndGetNodeStats() (*livekit.NodeStats, error) {
+	n.lock.Lock()
+	defer n.lock.Unlock()
+
+	stats, err := prometheus.GetNodeStats(
+		n.startedAt,
+		append(n.statsHistory[n.statsHistoryWritePtr:], n.statsHistory[0:n.statsHistoryWritePtr]...),
+		n.config.StatsRateMeasurementIntervals,
+	)
+	if err != nil {
+		logger.Errorw("could not update node stats", err)
+		return nil, err
+	}
+
+	n.statsHistory[n.statsHistoryWritePtr] = stats
+	n.statsHistoryWritePtr = (n.statsHistoryWritePtr + 1) % len(n.statsHistory)
+	return stats, nil
+}
+
+func (n *NodeStats) GetLatestNodeStats() *livekit.NodeStats {
+	n.lock.RLock()
+	defer n.lock.RUnlock()
+
+	latestPtr := (n.statsHistoryWritePtr - 1 + len(n.statsHistory)) % len(n.statsHistory)
+	return utils.CloneProto(n.statsHistory[latestPtr])
+}