const (
    // NetworkPluginOperationsKey is the key for operation count metrics.
    NetworkPluginOperationsKey = "network_plugin_operations"
    // NetworkPluginOperationsLatencyKey is the key for the operation latency metrics.
    NetworkPluginOperationsLatencyKey = "network_plugin_operations_duration_seconds"
)

var (
    // NetworkPluginOperationsLatency collects operation latency numbers by operation
    // type.
    NetworkPluginOperationsLatency = metrics.NewHistogramVec(
        &metrics.HistogramOpts{
            Subsystem:      kubeletSubsystem,
            Name:           NetworkPluginOperationsLatencyKey,
            Help:           "Latency in seconds of network plugin operations. Broken down by operation type.",
            Buckets:        metrics.DefBuckets,
            StabilityLevel: metrics.ALPHA,
        },
        []string{"operation_type"},
    )
)