go-redis/redis · error

failed to create connection wait time histogram: %w

Error message

failed to create connection wait time histogram: %w

What it means

Returned by createRecorder (redisotel.go:282) when dbconv.NewClientConnectionWaitTime fails to create the 'db.client.connection.wait_time' Float64Histogram. Only checked when MetricGroupConnectionAdvanced is enabled.

Source

Thrown at extra/redisotel-native/redisotel.go:282

			return nil, fmt.Errorf("failed to create maintenance notifications metric: %w", err)
		}
	}

	var connectionWaitTime metric.Float64Histogram
	var connectionClosed metric.Int64Counter
	var connectionPendingReqs metric.Int64UpDownCounter // OTel semconv: UpDownCounter

	if cfg.isMetricGroupEnabled(MetricGroupConnectionAdvanced) {
		var connectionWaitTimeOpts []metric.Float64HistogramOption
		if cfg.histAggregation == HistogramAggregationExplicitBucket {
			connectionWaitTimeOpts = append(connectionWaitTimeOpts,
				metric.WithExplicitBucketBoundaries(cfg.bucketsConnectionWaitTime...),
			)
		}
		var connectionWaitTimeConv dbconv.ClientConnectionWaitTime
		connectionWaitTimeConv, err = dbconv.NewClientConnectionWaitTime(meter, connectionWaitTimeOpts...)
		if err != nil {
			return nil, fmt.Errorf("failed to create connection wait time histogram: %w", err)
		}
		connectionWaitTime = connectionWaitTimeConv.Inst()

		connectionClosed, err = meter.Int64Counter(
			MetricConnectionClosed,
			metric.WithDescription("The number of connections that have been closed"),
			metric.WithUnit("{connection}"),
		)
		if err != nil {
			return nil, fmt.Errorf("failed to create connection closed metric: %w", err)
		}

		connectionPendingReqs, err = meter.Int64UpDownCounter(
			dbconv.ClientConnectionPendingRequests{}.Name(),
			metric.WithDescription(dbconv.ClientConnectionPendingRequests{}.Description()),
			metric.WithUnit(dbconv.ClientConnectionPendingRequests{}.Unit()),
		)
		if err != nil {

View on GitHub (pinned to 36d97525cd)

Solutions

1. Search for other registrations of 'db.client.connection.wait_time' and reconcile metadata
2. Validate cfg.BucketsConnectionWaitTime contains monotonically increasing positive floats
3. Verify OTel SDK compatibility

Example fix

// before - bucket boundaries invalid
cfg.BucketsConnectionWaitTime = []float64{0}

// after - valid positive monotonically increasing bounds
cfg.BucketsConnectionWaitTime = []float64{0.001, 0.01, 0.1, 1.0}

// Validate connection wait time bucket boundaries
for i := 1; i < len(cfg.BucketsConnectionWaitTime); i++ {
    if cfg.BucketsConnectionWaitTime[i] <= cfg.BucketsConnectionWaitTime[i-1] {
        return fmt.Errorf("invalid bucket boundaries")
    }
}

if err := obs.Init(cfg); err != nil {
    if strings.Contains(err.Error(), "connection wait time histogram") {
        log.Error("conflict on 'db.client.connection.wait_time' or invalid bucket boundaries")
    }
}

When it happens

Trigger: Calling Init with MetricGroupFlagConnectionAdvanced enabled, and the OTel SDK rejects the histogram creation.

Common situations: Another library registered 'db.client.connection.wait_time' with conflicting unit or description; malformed cfg.BucketsConnectionWaitTime boundary values.

Related errors

• failed to create connection create time histogram: %w
• failed to create operation duration histogram: %w
• failed to create connection count metric: %w
• failed to create connection relaxed timeout metric: %w
• failed to create connection handoff metric: %w

AI-assisted analysis of go-redis/redis@36d97525cd (2026-08-06). Data as JSON: /data/errors/50edce3fddbc3236.json. Report an issue: GitHub.