more metrics

cart-grain.go

@@ -112,6 +112,7 @@ func (c *CartGrain) HandleMessage(message *Message, isReplay bool) ([]byte, erro
 		now := time.Now().Unix()
 		message.TimeStamp = &now
 	}
+	grainMutations.Inc()
 	var err error
 	switch message.Type {
 	case AddRequestType:

grain-pool.go

@@ -81,6 +81,7 @@ func (p *GrainLocalPool) GetGrains() map[CartId]*CartGrain {
 func (p *GrainLocalPool) GetGrain(id CartId) (*CartGrain, error) {
 	var err error
 	grain, ok := p.grains[id]
+	grainLookups.Inc()
 	if grain == nil || !ok {
 		if len(p.grains) >= p.PoolSize {
 			if p.expiry[0].Expires.Before(time.Now()) {

main.go

@@ -14,14 +14,22 @@ import (
 )
 
 var (
-	opsProcessed = promauto.NewCounter(prometheus.CounterOpts{
+	grainSpawns = promauto.NewCounter(prometheus.CounterOpts{
 		Name: "cart_grain_spawned_total",
 		Help: "The total number of spawned grains",
 	})
+	grainMutations = promauto.NewCounter(prometheus.CounterOpts{
+		Name: "cart_grain_mutations_total",
+		Help: "The total number of mutations",
+	})
+	grainLookups = promauto.NewCounter(prometheus.CounterOpts{
+		Name: "cart_grain_lookups_total",
+		Help: "The total number of lookups",
+	})
 )
 
 func spawn(id CartId) (*CartGrain, error) {
-	opsProcessed.Inc()
+	grainSpawns.Inc()
 	ret := &CartGrain{
 		Id:              id,
 		Items:           []CartItem{},