Add namespace to container metrics

Signed-off-by: Michael Crosby <crosbymichael@gmail.com>

metrics/cgroups/cgroups.go

@@ -3,7 +3,6 @@
 package cgroups
 
 import (
-	"fmt"
 	"time"
 
 	"github.com/containerd/cgroups"
@@ -44,12 +43,8 @@ type cgroupsMonitor struct {
 	events    chan<- *plugin.Event
 }
 
-func getID(t plugin.Task) string {
-	return fmt.Sprintf("%s-%s", t.Info().Namespace, t.Info().ID)
-}
-
 func (m *cgroupsMonitor) Monitor(c plugin.Task) error {
-	id := getID(c)
+	info := c.Info()
 	state, err := c.State(m.context)
 	if err != nil {
 		return err
@@ -58,14 +53,15 @@ func (m *cgroupsMonitor) Monitor(c plugin.Task) error {
 	if err != nil {
 		return err
 	}
-	if err := m.collector.Add(id, cg); err != nil {
+	if err := m.collector.Add(info.ID, info.Namespace, cg); err != nil {
 		return err
 	}
-	return m.oom.Add(id, cg, m.trigger)
+	return m.oom.Add(info.ID, info.Namespace, cg, m.trigger)
 }
 
 func (m *cgroupsMonitor) Stop(c plugin.Task) error {
-	m.collector.Remove(getID(c))
+	info := c.Info()
+	m.collector.Remove(info.ID, info.Namespace)
 	return nil
 }
 

metrics/cgroups/metric.go

@@ -22,12 +22,13 @@ type metric struct {
 }
 
 func (m *metric) desc(ns *metrics.Namespace) *prometheus.Desc {
-	return ns.NewDesc(m.name, m.help, m.unit, append([]string{"id"}, m.labels...)...)
+	// the namespace label is for containerd namespaces
+	return ns.NewDesc(m.name, m.help, m.unit, append([]string{"id", "namespace"}, m.labels...)...)
 }
 
-func (m *metric) collect(id string, stats *cgroups.Stats, ns *metrics.Namespace, ch chan<- prometheus.Metric) {
+func (m *metric) collect(id, namespace string, stats *cgroups.Stats, ns *metrics.Namespace, ch chan<- prometheus.Metric) {
 	values := m.getValues(stats)
 	for _, v := range values {
-		ch <- prometheus.MustNewConstMetric(m.desc(ns), m.vt, v.v, append([]string{id}, v.l...)...)
+		ch <- prometheus.MustNewConstMetric(m.desc(ns), m.vt, v.v, append([]string{id, namespace}, v.l...)...)
 	}
 }

metrics/cgroups/metrics.go

@@ -26,7 +26,7 @@ func NewCollector(ns *metrics.Namespace) *Collector {
 	// add machine cpus and memory info
 	c := &Collector{
 		ns:      ns,
-		cgroups: make(map[string]cgroups.Cgroup),
+		cgroups: make(map[string]*task),
 	}
 	c.metrics = append(c.metrics, pidMetrics...)
 	c.metrics = append(c.metrics, cpuMetrics...)
@@ -37,12 +37,18 @@ func NewCollector(ns *metrics.Namespace) *Collector {
 	return c
 }
 
+type task struct {
+	id        string
+	namespace string
+	cgroup    cgroups.Cgroup
+}
+
 // Collector provides the ability to collect container stats and export
 // them in the prometheus format
 type Collector struct {
 	mu sync.RWMutex
 
-	cgroups map[string]cgroups.Cgroup
+	cgroups map[string]*task
 	ns      *metrics.Namespace
 	metrics []*metric
 }
@@ -56,15 +62,15 @@ func (c *Collector) Describe(ch chan<- *prometheus.Desc) {
 func (c *Collector) Collect(ch chan<- prometheus.Metric) {
 	c.mu.RLock()
 	wg := &sync.WaitGroup{}
-	for id, cg := range c.cgroups {
+	for _, t := range c.cgroups {
 		wg.Add(1)
-		go c.collect(id, cg, ch, wg)
+		go c.collect(t.id, t.namespace, t.cgroup, ch, wg)
 	}
 	c.mu.RUnlock()
 	wg.Wait()
 }
 
-func (c *Collector) collect(id string, cg cgroups.Cgroup, ch chan<- prometheus.Metric, wg *sync.WaitGroup) {
+func (c *Collector) collect(id, namespace string, cg cgroups.Cgroup, ch chan<- prometheus.Metric, wg *sync.WaitGroup) {
 	defer wg.Done()
 	stats, err := cg.Stat(cgroups.IgnoreNotExist)
 	if err != nil {
@@ -72,38 +78,42 @@ func (c *Collector) collect(id string, cg cgroups.Cgroup, ch chan<- prometheus.M
 		return
 	}
 	for _, m := range c.metrics {
-		m.collect(id, stats, c.ns, ch)
+		m.collect(id, namespace, stats, c.ns, ch)
 	}
 }
 
 // Add adds the provided cgroup and id so that metrics are collected and exported
-func (c *Collector) Add(id string, cg cgroups.Cgroup) error {
+func (c *Collector) Add(id, namespace string, cg cgroups.Cgroup) error {
 	c.mu.Lock()
 	defer c.mu.Unlock()
-	if _, ok := c.cgroups[id]; ok {
+	if _, ok := c.cgroups[id+namespace]; ok {
 		return ErrAlreadyCollected
 	}
-	c.cgroups[id] = cg
+	c.cgroups[id+namespace] = &task{
+		id:        id,
+		namespace: namespace,
+		cgroup:    cg,
+	}
 	return nil
 }
 
 // Get returns the cgroup that is being collected under the provided id
 // returns ErrCgroupNotExists if the id is not being collected
-func (c *Collector) Get(id string) (cgroups.Cgroup, error) {
+func (c *Collector) Get(id, namespace string) (cgroups.Cgroup, error) {
 	c.mu.Lock()
 	defer c.mu.Unlock()
-	cg, ok := c.cgroups[id]
+	t, ok := c.cgroups[id+namespace]
 	if !ok {
 		return nil, ErrCgroupNotExists
 	}
-	return cg, nil
+	return t.cgroup, nil
 }
 
 // Remove removes the provided cgroup by id from the collector
-func (c *Collector) Remove(id string) {
+func (c *Collector) Remove(id, namespace string) {
 	c.mu.Lock()
 	defer c.mu.Unlock()
-	delete(c.cgroups, id)
+	delete(c.cgroups, id+namespace)
 }
 
 func blkioValues(l []cgroups.BlkioEntry) []value {

metrics/cgroups/oom.go

@@ -17,7 +17,7 @@ func NewOOMCollector(ns *metrics.Namespace) (*OOMCollector, error) {
 	}
 	c := &OOMCollector{
 		fd:        fd,
-		memoryOOM: ns.NewLabeledGauge("memory_oom", "The number of times a container received an oom event", metrics.Total, "id"),
+		memoryOOM: ns.NewLabeledGauge("memory_oom", "The number of times a container received an oom event", metrics.Total, "id", "namespace"),
 		set:       make(map[uintptr]*oom),
 	}
 	go c.start()
@@ -33,12 +33,13 @@ type OOMCollector struct {
 }
 
 type oom struct {
-	id       string
-	c        cgroups.Cgroup
-	triggers []Trigger
+	id        string
+	namespace string
+	c         cgroups.Cgroup
+	triggers  []Trigger
 }
 
-func (o *OOMCollector) Add(id string, cg cgroups.Cgroup, triggers ...Trigger) error {
+func (o *OOMCollector) Add(id, namespace string, cg cgroups.Cgroup, triggers ...Trigger) error {
 	o.mu.Lock()
 	defer o.mu.Unlock()
 	fd, err := cg.OOMEventFD()
@@ -46,12 +47,13 @@ func (o *OOMCollector) Add(id string, cg cgroups.Cgroup, triggers ...Trigger) er
 		return err
 	}
 	o.set[fd] = &oom{
-		id:       id,
-		c:        cg,
-		triggers: triggers,
+		id:        id,
+		c:         cg,
+		triggers:  triggers,
+		namespace: namespace,
 	}
 	// set the gauge's default value
-	o.memoryOOM.WithValues(id).Set(0)
+	o.memoryOOM.WithValues(id, namespace).Set(0)
 	event := unix.EpollEvent{
 		Fd:     int32(fd),
 		Events: unix.EPOLLHUP | unix.EPOLLIN | unix.EPOLLERR,
@@ -103,7 +105,7 @@ func (o *OOMCollector) process(fd uintptr, event uint32) {
 		unix.Close(int(fd))
 		return
 	}
-	o.memoryOOM.WithValues(info.id).Inc(1)
+	o.memoryOOM.WithValues(info.id, info.namespace).Inc(1)
 	for _, t := range info.triggers {
 		t(info.id, info.c)
 	}