add lru cache metrics to telemetry package

pkg/agent/manager/cache/lru_cache.go

@@ -18,11 +18,6 @@ import (
 const (
 	DefaultSVIDCacheMaxSize = 1000
 	SVIDSyncInterval        = 500 * time.Millisecond
-	SVIDMapSize             = "lru_cache_svid_map_size"
-	RecordMapSize           = "lru_cache_record_map_size"
-	EntryAdded              = "lru_cache_entry_add"
-	EntryUpdated            = "lru_cache_entry_update"
-	EntryRemoved            = "lru_cache_entry_remove"
 )
 
 // Cache caches each registration entry, bundles, and JWT SVIDs for the agent.
@@ -88,7 +83,7 @@ type LRUCache struct {
 	trustDomain spiffeid.TrustDomain
 	clk         clock.Clock
 
-	metrics telemetry.Metrics
+	metrics *telemetry.LRUMetrics
 
 	mu sync.RWMutex
 
@@ -123,7 +118,7 @@ func NewLRUCache(log logrus.FieldLogger, trustDomain spiffeid.TrustDomain, bundl
 		JWTSVIDCache: NewJWTSVIDCache(),
 
 		log:          log,
-		metrics:      metrics,
+		metrics:      telemetry.NewLRUMetrics(&telemetry.LRUConfig{MetricsImpl: metrics}),
 		trustDomain:  trustDomain,
 		records:      make(map[string]*lruCacheRecord),
 		selectors:    make(map[selector]*selectorsMapIndex),
@@ -226,7 +221,7 @@ func (c *LRUCache) NewSubscriber(selectors []*common.Selector) Subscriber {
 // updated through a call to UpdateSVIDs.
 func (c *LRUCache) UpdateEntries(update *UpdateEntries, checkSVID func(*common.RegistrationEntry, *common.RegistrationEntry, *X509SVID) bool) {
 	c.mu.Lock()
-	defer func() { c.metrics.SetGauge([]string{RecordMapSize}, float32(c.CountRecords())) }()
+	defer func() { c.metrics.SetEntriesMapSize(c.CountRecords()) }()
 	defer c.mu.Unlock()
 
 	// Remove bundles that no longer exist. The bundle for the agent trust
@@ -298,7 +293,7 @@ func (c *LRUCache) UpdateEntries(update *UpdateEntries, checkSVID func(*common.R
 			delete(c.staleEntries, id)
 		}
 	}
-	c.metrics.IncrCounter([]string{EntryRemoved}, float32(entriesRemoved))
+	c.metrics.IncrementEntriesRemoved(entriesRemoved)
 
 	outdatedEntries := make(map[string]struct{})
 	entriesUpdated := 0
@@ -391,8 +386,8 @@ func (c *LRUCache) UpdateEntries(update *UpdateEntries, checkSVID func(*common.R
 			}
 		}
 	}
-	c.metrics.IncrCounter([]string{EntryUpdated}, float32(entriesUpdated))
-	c.metrics.IncrCounter([]string{EntryAdded}, float32(entriesCreated))
+	c.metrics.IncrementEntriesAdded(entriesCreated)
+	c.metrics.IncrementEntriesUpdated(entriesUpdated)
 
 	// entries with active subscribers which are not cached will be put in staleEntries map;
 	// irrespective of what svid cache size as we cannot deny identity to a subscriber
@@ -444,7 +439,7 @@ func (c *LRUCache) UpdateEntries(update *UpdateEntries, checkSVID func(*common.R
 
 func (c *LRUCache) UpdateSVIDs(update *UpdateSVIDs) {
 	c.mu.Lock()
-	defer func() { c.metrics.SetGauge([]string{SVIDMapSize}, float32(c.CountSVIDs())) }()
+	defer func() { c.metrics.SetSVIDMapSize(c.CountSVIDs()) }()
 	defer c.mu.Unlock()
 
 	// Allocate a set of selectors that

pkg/agent/manager/cache/lru_cache_test.go

@@ -889,7 +889,7 @@ func TestSubscribeToLRUCacheChanges(t *testing.T) {
 func TestMetrics(t *testing.T) {
 	cache := newTestLRUCache(t)
 	fakeMetrics := fakemetrics.New()
-	cache.metrics = fakeMetrics
+	cache.metrics = telemetry.NewLRUMetrics(&telemetry.LRUConfig{MetricsImpl: fakeMetrics})
 
 	foo := makeRegistrationEntry("FOO", "A")
 	bar := makeRegistrationEntry("BAR", "B")
@@ -911,19 +911,19 @@ func TestMetrics(t *testing.T) {
 	cache.UpdateEntries(updateEntries, nil)
 
 	assert.Equal(t, []fakemetrics.MetricItem{
-		{Type: fakemetrics.IncrCounterType, Key: []string{EntryRemoved}, Val: 0},
-		{Type: fakemetrics.IncrCounterType, Key: []string{EntryUpdated}, Val: 0},
-		{Type: fakemetrics.IncrCounterType, Key: []string{EntryAdded}, Val: 2},
-		{Type: fakemetrics.SetGaugeType, Key: []string{RecordMapSize}, Val: 2},
-		{Type: fakemetrics.SetGaugeType, Key: []string{SVIDMapSize}, Val: 1},
-		{Type: fakemetrics.IncrCounterType, Key: []string{EntryRemoved}, Val: 1},
-		{Type: fakemetrics.IncrCounterType, Key: []string{EntryUpdated}, Val: 1},
-		{Type: fakemetrics.IncrCounterType, Key: []string{EntryAdded}, Val: 0},
-		{Type: fakemetrics.SetGaugeType, Key: []string{RecordMapSize}, Val: 1},
-		{Type: fakemetrics.IncrCounterType, Key: []string{EntryRemoved}, Val: 0},
-		{Type: fakemetrics.IncrCounterType, Key: []string{EntryUpdated}, Val: 1},
-		{Type: fakemetrics.IncrCounterType, Key: []string{EntryAdded}, Val: 1},
-		{Type: fakemetrics.SetGaugeType, Key: []string{RecordMapSize}, Val: 2},
+		{Type: fakemetrics.IncrCounterType, Key: []string{telemetry.EntryRemoved}, Val: 0},
+		{Type: fakemetrics.IncrCounterType, Key: []string{telemetry.EntryAdded}, Val: 2},
+		{Type: fakemetrics.IncrCounterType, Key: []string{telemetry.EntryUpdated}, Val: 0},
+		{Type: fakemetrics.SetGaugeType, Key: []string{telemetry.RecordMapSize}, Val: 2},
+		{Type: fakemetrics.SetGaugeType, Key: []string{telemetry.SVIDMapSize}, Val: 1},
+		{Type: fakemetrics.IncrCounterType, Key: []string{telemetry.EntryRemoved}, Val: 1},
+		{Type: fakemetrics.IncrCounterType, Key: []string{telemetry.EntryAdded}, Val: 0},
+		{Type: fakemetrics.IncrCounterType, Key: []string{telemetry.EntryUpdated}, Val: 1},
+		{Type: fakemetrics.SetGaugeType, Key: []string{telemetry.RecordMapSize}, Val: 1},
+		{Type: fakemetrics.IncrCounterType, Key: []string{telemetry.EntryRemoved}, Val: 0},
+		{Type: fakemetrics.IncrCounterType, Key: []string{telemetry.EntryAdded}, Val: 1},
+		{Type: fakemetrics.IncrCounterType, Key: []string{telemetry.EntryUpdated}, Val: 1},
+		{Type: fakemetrics.SetGaugeType, Key: []string{telemetry.RecordMapSize}, Val: 2},
 	}, fakeMetrics.AllMetrics())
 }
 

pkg/common/telemetry/config.go

@@ -52,3 +52,7 @@ type M3Config struct {
 type InMem struct {
 	UnusedKeyPositions map[string][]token.Pos `hcl:",unusedKeyPositions"`
 }
+
+type LRUConfig struct {
+	MetricsImpl Metrics
+}

pkg/common/telemetry/lru.go

@@ -0,0 +1,46 @@
+package telemetry
+
+import (
+	"sync"
+)
+
+type LRUMetrics struct {
+	metrics Metrics
+	mu      sync.Mutex
+}
+
+func NewLRUMetrics(c *LRUConfig) *LRUMetrics {
+	return &LRUMetrics{
+		metrics: c.MetricsImpl,
+	}
+}
+
+func (c *LRUMetrics) IncrementEntriesAdded(entriesAdded int) {
+	c.mu.Lock()
+	defer c.mu.Unlock()
+	c.metrics.IncrCounter([]string{EntryAdded}, float32(entriesAdded))
+}
+
+func (c *LRUMetrics) IncrementEntriesUpdated(entriesUpdated int) {
+	c.mu.Lock()
+	defer c.mu.Unlock()
+	c.metrics.IncrCounter([]string{EntryUpdated}, float32(entriesUpdated))
+}
+
+func (c *LRUMetrics) IncrementEntriesRemoved(entriesRemoved int) {
+	c.mu.Lock()
+	defer c.mu.Unlock()
+	c.metrics.IncrCounter([]string{EntryRemoved}, float32(entriesRemoved))
+}
+
+func (c *LRUMetrics) SetEntriesMapSize(recordMapSize int) {
+	c.mu.Lock()
+	defer c.mu.Unlock()
+	c.metrics.SetGauge([]string{RecordMapSize}, float32(recordMapSize))
+}
+
+func (c *LRUMetrics) SetSVIDMapSize(svidMapSize int) {
+	c.mu.Lock()
+	defer c.mu.Unlock()
+	c.metrics.SetGauge([]string{SVIDMapSize}, float32(svidMapSize))
+}

pkg/common/telemetry/names.go

@@ -263,6 +263,15 @@ const (
 	// ElapsedTime tags some duration of time.
 	ElapsedTime = "elapsed_time"
 
+	// EntryAdded is the counter key for when a entry is added to LRU cache
+	EntryAdded = "lru_cache_entry_add"
+
+	// EntryRemoved is the counter key for when a entry is removed from LRU cache
+	EntryRemoved = "lru_cache_entry_remove"
+
+	// EntryUpdated is the counter key for when an LRU cache entry is updated
+	EntryUpdated = "lru_cache_entry_update"
+
 	// EndpointSpiffeID tags endpoint SPIFFE ID
 	EndpointSpiffeID = "endpoint_spiffe_id"
 
@@ -415,6 +424,9 @@ const (
 	// ReceivedUID is like Received, specific to uid.
 	ReceivedUID = "received_uid"
 
+	// RecordMapSize is the gauge key to hold the size of the LRU cache entries map
+	RecordMapSize = "lru_cache_record_map_size"
+
 	// RefreshHint tags a bundle refresh hint
 	RefreshHint = "refresh_hint"
 
@@ -493,6 +505,9 @@ const (
 	// with other tags to add clarity
 	Subject = "subject"
 
+	// SVIDMapSize is the gauge key for the size of the LRU cache SVID map
+	SVIDMapSize = "lru_cache_svid_map_size"
+
 	// SVIDResponseLatency tags latency for SVID response
 	SVIDResponseLatency = "svid_response_latency"