cockroach: github.com/cockroachdb/cockroach/pkg/util/metric Index | Files

package metric

import "github.com/cockroachdb/cockroach/pkg/util/metric"

Package metric provides server metrics (a.k.a. transient stats) for a CockroachDB server. These metrics are persisted to the time-series database and are viewable through the web interface and the /_status/metrics/<NODEID> HTTP endpoint.

Adding a new metric

First, add the metric to a Registry.

Next, call methods such as Counter() and Rate() on the Registry to register the metric. For example:

exec := &Executor{
	...
	selectCount: sqlRegistry.Counter("sql.select.count"),
	...
}

This code block registers the metric "sql.select.count" in sql.Registry. The metric can then be accessed through the "selectCount" variable, which can be updated as follows:

func (e *Executor) doSelect() {
	// do the SELECT
	e.selectCount.Inc(1)
}

To add the metric to the web UI, modify the appropriate file in "ui/ts/pages/*.ts". Someone more qualified than me can elaborate, like @maxlang.

Sub-registries

It's common for a Registry to become part of another Registry through the "Add" and "MustAdd" methods.

func NewNodeStatusMonitor(serverRegistry *registry) {
	nodeRegistry := metric.NewRegistry()

	// Add the registry for this node to the root-level server Registry. When
	// accessed from through the serverRegistry, all metrics from the
	// nodeRegistry will have the prefix "cr.node.".
	serverRegistry.MustAdd("cr.node.%s", nodeRegistry)
}

Node-level sub-registries are added by calling:

(*metric.MetricRecorder).AddNodeRegistry(YOUR_NODE_SUBREGISTRY)

Testing

After your test does something to trigger your new metric update, you'll probably want to call methods in TestServer such as MustGetSQLCounter() to verify that the metric was updated correctly. See "sql/metric_test.go" for an example.

Additionally, you can manually verify that your metric is updating by using the metrics endpoint. For example, if you're running the Cockroach DB server with the "--insecure" flag, you can use access the endpoint as follows:

$ curl http://localhost:8080/_status/nodes/1

(some other output)
"cr.node.sql.select.count.1": 5,
(some other output)

Note that a prefix and suffix have been added. The prefix "cr.node." denotes that this metric is node-level. The suffix ".1" specifies that this metric is for node 1.

Index

Package Files

doc.go graphite_exporter.go metric.go metric.pb.go prometheus_exporter.go registry.go sliding_histogram.go

Constants

const (
    // MaxLatency is the maximum value tracked in latency histograms. Higher
    // values will be recorded as this value instead.
    MaxLatency = 10 * time.Second

    // TestSampleInterval is passed to histograms during tests which don't
    // want to concern themselves with supplying a "correct" interval.
    TestSampleInterval = time.Duration(math.MaxInt64)
)

Variables

var (
    ErrInvalidLengthMetric = fmt.Errorf("proto: negative length found during unmarshaling")
    ErrIntOverflowMetric   = fmt.Errorf("proto: integer overflow")
)
var Unit_name = map[int32]string{
    0:  "UNSET",
    1:  "BYTES",
    2:  "CONST",
    3:  "COUNT",
    4:  "NANOSECONDS",
    5:  "PERCENT",
    6:  "SECONDS",
    7:  "TIMESTAMP_NS",
    8:  "TIMESTAMP_SEC",
}
var Unit_value = map[string]int32{
    "UNSET":         0,
    "BYTES":         1,
    "CONST":         2,
    "COUNT":         3,
    "NANOSECONDS":   4,
    "PERCENT":       5,
    "SECONDS":       6,
    "TIMESTAMP_NS":  7,
    "TIMESTAMP_SEC": 8,
}

func TestingSetNow Uses

func TestingSetNow(f func() time.Time) func()

TestingSetNow changes the clock used by the metric system. For use by testing to precisely control the clock.

type Counter Uses

type Counter struct {
    Metadata
    metrics.Counter
}

A Counter holds a single mutable atomic value.

func NewCounter Uses

func NewCounter(metadata Metadata) *Counter

NewCounter creates a counter.

func (*Counter) Dec Uses

func (c *Counter) Dec(int64)

Dec overrides the metric.Counter method. This method should NOT be used and serves only to prevent misuse of the metric type.

func (*Counter) GetMetadata Uses

func (c *Counter) GetMetadata() Metadata

GetMetadata returns the metric's metadata including the Prometheus MetricType.

func (*Counter) GetType Uses

func (c *Counter) GetType() *prometheusgo.MetricType

GetType returns the prometheus type enum for this metric.

func (*Counter) Inspect Uses

func (c *Counter) Inspect(f func(interface{}))

Inspect calls the given closure with the empty string and itself.

func (*Counter) MarshalJSON Uses

func (c *Counter) MarshalJSON() ([]byte, error)

MarshalJSON marshals to JSON.

func (*Counter) ToPrometheusMetric Uses

func (c *Counter) ToPrometheusMetric() *prometheusgo.Metric

ToPrometheusMetric returns a filled-in prometheus metric of the right type.

type Gauge Uses

type Gauge struct {
    Metadata
    // contains filtered or unexported fields
}

A Gauge atomically stores a single integer value.

func NewFunctionalGauge Uses

func NewFunctionalGauge(metadata Metadata, f func() int64) *Gauge

NewFunctionalGauge creates a Gauge metric whose value is determined when asked for by calling the provided function. Note that Update, Inc, and Dec should NOT be called on a Gauge returned from NewFunctionalGauge.

func NewGauge Uses

func NewGauge(metadata Metadata) *Gauge

NewGauge creates a Gauge.

func (*Gauge) Dec Uses

func (g *Gauge) Dec(i int64)

Dec decrements the gauge's value.

func (*Gauge) GetMetadata Uses

func (g *Gauge) GetMetadata() Metadata

GetMetadata returns the metric's metadata including the Prometheus MetricType.

func (*Gauge) GetType Uses

func (g *Gauge) GetType() *prometheusgo.MetricType

GetType returns the prometheus type enum for this metric.

func (*Gauge) Inc Uses

func (g *Gauge) Inc(i int64)

Inc increments the gauge's value.

func (*Gauge) Inspect Uses

func (g *Gauge) Inspect(f func(interface{}))

Inspect calls the given closure with the empty string and itself.

func (*Gauge) MarshalJSON Uses

func (g *Gauge) MarshalJSON() ([]byte, error)

MarshalJSON marshals to JSON.

func (*Gauge) Snapshot Uses

func (g *Gauge) Snapshot() metrics.Gauge

Snapshot returns a read-only copy of the gauge.

func (*Gauge) ToPrometheusMetric Uses

func (g *Gauge) ToPrometheusMetric() *prometheusgo.Metric

ToPrometheusMetric returns a filled-in prometheus metric of the right type.

func (*Gauge) Update Uses

func (g *Gauge) Update(v int64)

Update updates the gauge's value.

func (*Gauge) Value Uses

func (g *Gauge) Value() int64

Value returns the gauge's current value.

type GaugeFloat64 Uses

type GaugeFloat64 struct {
    Metadata
    metrics.GaugeFloat64
}

A GaugeFloat64 atomically stores a single float64 value.

func NewGaugeFloat64 Uses

func NewGaugeFloat64(metadata Metadata) *GaugeFloat64

NewGaugeFloat64 creates a GaugeFloat64.

func (*GaugeFloat64) GetMetadata Uses

func (g *GaugeFloat64) GetMetadata() Metadata

GetMetadata returns the metric's metadata including the Prometheus MetricType.

func (*GaugeFloat64) GetType Uses

func (g *GaugeFloat64) GetType() *prometheusgo.MetricType

GetType returns the prometheus type enum for this metric.

func (*GaugeFloat64) Inspect Uses

func (g *GaugeFloat64) Inspect(f func(interface{}))

Inspect calls the given closure with itself.

func (*GaugeFloat64) MarshalJSON Uses

func (g *GaugeFloat64) MarshalJSON() ([]byte, error)

MarshalJSON marshals to JSON.

func (*GaugeFloat64) ToPrometheusMetric Uses

func (g *GaugeFloat64) ToPrometheusMetric() *prometheusgo.Metric

ToPrometheusMetric returns a filled-in prometheus metric of the right type.

type GraphiteExporter Uses

type GraphiteExporter struct {
    // contains filtered or unexported fields
}

GraphiteExporter scrapes PrometheusExporter for metrics and pushes them to a Graphite or Carbon server.

func MakeGraphiteExporter Uses

func MakeGraphiteExporter(pm *PrometheusExporter) GraphiteExporter

MakeGraphiteExporter returns an initialized graphite exporter.

func (*GraphiteExporter) Push Uses

func (ge *GraphiteExporter) Push(ctx context.Context, endpoint string) error

Push metrics scraped from registry to Graphite or Carbon server. It converts the same metrics that are pulled by Prometheus into Graphite-format.

type Histogram Uses

type Histogram struct {
    Metadata
    // contains filtered or unexported fields
}

A Histogram collects observed values by keeping bucketed counts. For convenience, internally two sets of buckets are kept: A cumulative set (i.e. data is never evicted) and a windowed set (which keeps only recently collected samples).

Top-level methods generally apply to the cumulative buckets; the windowed variant is exposed through the Windowed method.

func NewHistogram Uses

func NewHistogram(metadata Metadata, duration time.Duration, maxVal int64, sigFigs int) *Histogram

NewHistogram initializes a given Histogram. The contained windowed histogram rotates every 'duration'; both the windowed and the cumulative histogram track nonnegative values up to 'maxVal' with 'sigFigs' decimal points of precision.

func NewLatency Uses

func NewLatency(metadata Metadata, histogramWindow time.Duration) *Histogram

NewLatency is a convenience function which returns a histogram with suitable defaults for latency tracking. Values are expressed in ns, are truncated into the interval [0, MaxLatency] and are recorded with one digit of precision (i.e. errors of <10ms at 100ms, <6s at 60s).

The windowed portion of the Histogram retains values for approximately histogramWindow.

func (*Histogram) GetMetadata Uses

func (h *Histogram) GetMetadata() Metadata

GetMetadata returns the metric's metadata including the Prometheus MetricType.

func (*Histogram) GetType Uses

func (h *Histogram) GetType() *prometheusgo.MetricType

GetType returns the prometheus type enum for this metric.

func (*Histogram) Inspect Uses

func (h *Histogram) Inspect(f func(interface{}))

Inspect calls the closure with the empty string and the receiver.

func (*Histogram) Min Uses

func (h *Histogram) Min() int64

Min returns the minimum.

func (*Histogram) RecordValue Uses

func (h *Histogram) RecordValue(v int64)

RecordValue adds the given value to the histogram. Recording a value in excess of the configured maximum value for that histogram results in recording the maximum value instead.

func (*Histogram) Snapshot Uses

func (h *Histogram) Snapshot() *hdrhistogram.Histogram

Snapshot returns a copy of the cumulative (i.e. all-time samples) histogram data.

func (*Histogram) ToPrometheusMetric Uses

func (h *Histogram) ToPrometheusMetric() *prometheusgo.Metric

ToPrometheusMetric returns a filled-in prometheus metric of the right type.

func (*Histogram) TotalCount Uses

func (h *Histogram) TotalCount() int64

TotalCount returns the (cumulative) number of samples.

func (*Histogram) Windowed Uses

func (h *Histogram) Windowed() (*hdrhistogram.Histogram, time.Duration)

Windowed returns a copy of the current windowed histogram data and its rotation interval.

type Iterable Uses

type Iterable interface {
    // GetName returns the fully-qualified name of the metric.
    GetName() string
    // GetHelp returns the help text for the metric.
    GetHelp() string
    // GetMeasurement returns the label for the metric, which describes the entity
    // it measures.
    GetMeasurement() string
    // GetUnit returns the unit that should be used to display the metric
    // (e.g. in bytes).
    GetUnit() Unit
    // GetMetadata returns the metric's metadata, which can be used in charts.
    GetMetadata() Metadata
    // Inspect calls the given closure with each contained item.
    Inspect(func(interface{}))
}

Iterable provides a method for synchronized access to interior objects.

type LabelPair Uses

type LabelPair struct {
    Name  *string `protobuf:"bytes,1,opt,name=name" json:"name,omitempty"`
    Value *string `protobuf:"bytes,2,opt,name=value" json:"value,omitempty"`
}

metric.LabelPair is a proxy for io.prometheus.client.LabelPair. io.prometheus.client.LabelPair doesn't support gogoproto.marshaler and gogoproto.unmarshaler which are required by gRPC. metric.LabelPair stores information that is similarly structured, supports the requisite gogoproto options, and is convertible to io.prometheus.client.LabelPair to satisfy PrometheusExportable's GetLabels method.

func (*LabelPair) Descriptor Uses

func (*LabelPair) Descriptor() ([]byte, []int)

func (*LabelPair) Marshal Uses

func (m *LabelPair) Marshal() (dAtA []byte, err error)

func (*LabelPair) MarshalTo Uses

func (m *LabelPair) MarshalTo(dAtA []byte) (int, error)

func (*LabelPair) ProtoMessage Uses

func (*LabelPair) ProtoMessage()

func (*LabelPair) Reset Uses

func (m *LabelPair) Reset()

func (*LabelPair) Size Uses

func (m *LabelPair) Size() (n int)

func (*LabelPair) String Uses

func (m *LabelPair) String() string

func (*LabelPair) Unmarshal Uses

func (m *LabelPair) Unmarshal(dAtA []byte) error

func (*LabelPair) XXX_DiscardUnknown Uses

func (m *LabelPair) XXX_DiscardUnknown()

func (*LabelPair) XXX_Marshal Uses

func (m *LabelPair) XXX_Marshal(b []byte, deterministic bool) ([]byte, error)

func (*LabelPair) XXX_Merge Uses

func (dst *LabelPair) XXX_Merge(src proto.Message)

func (*LabelPair) XXX_Size Uses

func (m *LabelPair) XXX_Size() int

func (*LabelPair) XXX_Unmarshal Uses

func (m *LabelPair) XXX_Unmarshal(b []byte) error

type Metadata Uses

type Metadata struct {
    Name        string         `protobuf:"bytes,1,req,name=name" json:"name"`
    Help        string         `protobuf:"bytes,2,req,name=help" json:"help"`
    Measurement string         `protobuf:"bytes,3,req,name=measurement" json:"measurement"`
    Unit        Unit           `protobuf:"varint,4,req,name=unit,enum=cockroach.util.metric.Unit" json:"unit"`
    MetricType  _go.MetricType `protobuf:"varint,5,opt,name=metricType,enum=io.prometheus.client.MetricType" json:"metricType"`
    Labels      []*LabelPair   `protobuf:"bytes,6,rep,name=labels" json:"labels,omitempty"`
}

Metadata holds metadata about a metric. It must be embedded in each metric object. It's used to export information about the metric to Prometheus and for Admin UI charts.

func (*Metadata) AddLabel Uses

func (m *Metadata) AddLabel(name, value string)

AddLabel adds a label/value pair for this metric.

func (*Metadata) Descriptor Uses

func (*Metadata) Descriptor() ([]byte, []int)

func (*Metadata) GetHelp Uses

func (m *Metadata) GetHelp() string

GetHelp returns the metric's help string.

func (*Metadata) GetLabels Uses

func (m *Metadata) GetLabels() []*prometheusgo.LabelPair

GetLabels returns the metric's labels. For rationale behind the conversion from metric.LabelPair to prometheusgo.LabelPair, see the LabelPair comment in pkg/util/metric/metric.proto.

func (*Metadata) GetMeasurement Uses

func (m *Metadata) GetMeasurement() string

GetMeasurement returns the entity measured by the metric.

func (*Metadata) GetName Uses

func (m *Metadata) GetName() string

GetName returns the metric's name.

func (*Metadata) GetUnit Uses

func (m *Metadata) GetUnit() Unit

GetUnit returns the metric's unit of measurement.

func (*Metadata) Marshal Uses

func (m *Metadata) Marshal() (dAtA []byte, err error)

func (*Metadata) MarshalTo Uses

func (m *Metadata) MarshalTo(dAtA []byte) (int, error)

func (*Metadata) ProtoMessage Uses

func (*Metadata) ProtoMessage()

func (*Metadata) Reset Uses

func (m *Metadata) Reset()

func (*Metadata) Size Uses

func (m *Metadata) Size() (n int)

func (*Metadata) String Uses

func (m *Metadata) String() string

func (*Metadata) Unmarshal Uses

func (m *Metadata) Unmarshal(dAtA []byte) error

func (*Metadata) XXX_DiscardUnknown Uses

func (m *Metadata) XXX_DiscardUnknown()

func (*Metadata) XXX_Marshal Uses

func (m *Metadata) XXX_Marshal(b []byte, deterministic bool) ([]byte, error)

func (*Metadata) XXX_Merge Uses

func (dst *Metadata) XXX_Merge(src proto.Message)

func (*Metadata) XXX_Size Uses

func (m *Metadata) XXX_Size() int

func (*Metadata) XXX_Unmarshal Uses

func (m *Metadata) XXX_Unmarshal(b []byte) error

type PrometheusExportable Uses

type PrometheusExportable interface {
    // GetName is a method on Metadata
    GetName() string
    // GetHelp is a method on Metadata
    GetHelp() string
    // GetType returns the prometheus type enum for this metric.
    GetType() *prometheusgo.MetricType
    // GetLabels is a method on Metadata
    GetLabels() []*prometheusgo.LabelPair
    // ToPrometheusMetric returns a filled-in prometheus metric of the right type
    // for the given metric. It does not fill in labels.
    // The implementation must return thread-safe data to the caller, i.e.
    // usually a copy of internal state.
    ToPrometheusMetric() *prometheusgo.Metric
}

PrometheusExportable is the standard interface for an individual metric that can be exported to prometheus.

type PrometheusExporter Uses

type PrometheusExporter struct {
    // contains filtered or unexported fields
}

PrometheusExporter contains a map of metric families (a metric with multiple labels). It initializes each metric family once and reuses it for each prometheus scrape. It is NOT thread-safe. TODO(marc): we should really keep our metric objects here so we can avoid creating new prometheus.Metric every time we are scraped. see: https://github.com/cockroachdb/cockroach/issues/9326

pe := MakePrometheusExporter()
pe.AddMetricsFromRegistry(nodeRegistry)
pe.AddMetricsFromRegistry(storeOneRegistry)
...
pe.AddMetricsFromRegistry(storeNRegistry)
pe.Export(w)

func MakePrometheusExporter Uses

func MakePrometheusExporter() PrometheusExporter

MakePrometheusExporter returns an initialized prometheus exporter.

func (*PrometheusExporter) Gather Uses

func (pm *PrometheusExporter) Gather() ([]*prometheusgo.MetricFamily, error)

Gather implements prometheus.Gatherer

func (*PrometheusExporter) PrintAsText Uses

func (pm *PrometheusExporter) PrintAsText(w io.Writer) error

PrintAsText writes all metrics in the families map to the io.Writer in prometheus' text format. It removes individual metrics from the families as it goes, readying the families for another found of registry additions.

func (*PrometheusExporter) ScrapeRegistry Uses

func (pm *PrometheusExporter) ScrapeRegistry(registry *Registry)

ScrapeRegistry scrapes all metrics contained in the registry to the metric family map, holding on only to the scraped data (which is no longer connected to the registry and metrics within) when returning from the the call. It creates new families as needed.

type Rate Uses

type Rate struct {
    Metadata
    // contains filtered or unexported fields
}

A Rate is a exponential weighted moving average.

func NewRate Uses

func NewRate(metadata Metadata, timescale time.Duration) *Rate

NewRate creates an EWMA rate on the given timescale. Timescales at or below 2s are illegal and will cause a panic.

func (*Rate) Add Uses

func (e *Rate) Add(v float64)

Add adds the given measurement to the Rate.

func (*Rate) GetMetadata Uses

func (e *Rate) GetMetadata() Metadata

GetMetadata returns the metric's metadata including the Prometheus MetricType.

func (*Rate) GetType Uses

func (e *Rate) GetType() *prometheusgo.MetricType

GetType returns the prometheus type enum for this metric.

func (*Rate) Inspect Uses

func (e *Rate) Inspect(f func(interface{}))

Inspect calls the given closure with itself.

func (*Rate) MarshalJSON Uses

func (e *Rate) MarshalJSON() ([]byte, error)

MarshalJSON marshals to JSON.

func (*Rate) ToPrometheusMetric Uses

func (e *Rate) ToPrometheusMetric() *prometheusgo.Metric

ToPrometheusMetric returns a filled-in prometheus metric of the right type.

func (*Rate) Value Uses

func (e *Rate) Value() float64

Value returns the current value of the Rate.

type Registry Uses

type Registry struct {
    syncutil.Mutex
    // contains filtered or unexported fields
}

A Registry is a list of metrics. It provides a simple way of iterating over them, can marshal into JSON, and generate a prometheus format.

A registry can have label pairs that will be applied to all its metrics when exported to prometheus.

func NewRegistry Uses

func NewRegistry() *Registry

NewRegistry creates a new Registry.

func (*Registry) AddLabel Uses

func (r *Registry) AddLabel(name, value string)

AddLabel adds a label/value pair for this registry.

func (*Registry) AddMetric Uses

func (r *Registry) AddMetric(metric Iterable)

AddMetric adds the passed-in metric to the registry.

func (*Registry) AddMetricStruct Uses

func (r *Registry) AddMetricStruct(metricStruct interface{})

AddMetricStruct examines all fields of metricStruct and adds all Iterable or metric.Struct objects to the registry.

func (*Registry) Each Uses

func (r *Registry) Each(f func(name string, val interface{}))

Each calls the given closure for all metrics.

func (*Registry) MarshalJSON Uses

func (r *Registry) MarshalJSON() ([]byte, error)

MarshalJSON marshals to JSON.

func (*Registry) WriteMetricsMetadata Uses

func (r *Registry) WriteMetricsMetadata(dest map[string]Metadata)

WriteMetricsMetadata writes metadata from all tracked metrics to the parameter map.

type Struct Uses

type Struct interface {
    MetricStruct()
}

Struct can be implemented by the types of members of a metric container so that the members get automatically registered.

type Unit Uses

type Unit int32

DisplayUnit describes how the metric's units should be displayed in charts.

const (
    // UNSET expresses that the metric's DisplayUnit wasn't explicitly set.
    Unit_UNSET Unit = 0
    // BYTES expresses that the metric's measurement is in bytes.
    Unit_BYTES Unit = 1
    // CONST expresses that the metric's measurement is a constant value.
    Unit_CONST Unit = 2
    // COUNT expresses that the metric's measurement is a count.
    Unit_COUNT Unit = 3
    // NANOSECONDS expresses that the metric's measurement is in nanoseconds.
    Unit_NANOSECONDS Unit = 4
    // PERCENT expresses that the metric's measurement is a percentage value.
    Unit_PERCENT Unit = 5
    // SECONDS expresses that the metric's measurement is in seconds.
    Unit_SECONDS Unit = 6
    // TIMESTAMP_NS expresses that the metric's measurement is a time since the
    // Unix epoch in nanoseconds.
    Unit_TIMESTAMP_NS Unit = 7
    // TIMESTAMP_SEC expresses that the metric's measurement is a time since the
    // Unix epoch in seconds.
    Unit_TIMESTAMP_SEC Unit = 8
)

func (Unit) Enum Uses

func (x Unit) Enum() *Unit

func (Unit) EnumDescriptor Uses

func (Unit) EnumDescriptor() ([]byte, []int)

func (Unit) String Uses

func (x Unit) String() string

func (*Unit) UnmarshalJSON Uses

func (x *Unit) UnmarshalJSON(data []byte) error

Package metric imports 22 packages (graph) and is imported by 196 packages. Updated 2019-06-27. Refresh now. Tools for package owners.