feat: record number of empty STI responses

metrics/definitions.go

@@ -13,7 +13,7 @@ var (
 	defaultMillisecondsDistribution = view.Distribution(0.01, 0.05, 0.1, 0.3, 0.6, 0.8, 1, 2, 3, 4, 5, 6, 8, 10, 13, 16, 20, 25, 30, 40, 50, 65, 80, 100, 130, 160, 200, 250, 300, 400, 500, 650, 800, 1000, 2000, 5000, 10000, 20000, 50000, 100000)
 	// a coarser-grained milliseconds distribution for metrics with higher cardinality and where we don't need a more fine-grained distribution
 	coarseMillisecondsDistribution = view.Distribution(0, 1, 2, 5, 10, 20, 50, 100, 200, 500, 1000, 2000, 5000, 10000, 20000)
-	defaultProvidersDistribution   = view.Distribution(0, 1, 2, 5, 10, 20, 50, 100, 200, 500, 1000, 2000, 5000, 10000)
+	defaultProvidersDistribution   = view.Distribution(0.5, 1, 2, 5, 10, 20, 50, 100, 200, 500, 1000, 2000, 5000, 10000)
 )
 
 // Keys
@@ -69,6 +69,7 @@ var (
 	STIFindProvs         = stats.Int64("sti_find_provs_total", "Total store the index find provider attempts that were found locally, or not found locally and succeeded, failed or were discarded", stats.UnitDimensionless)
 	STIFindProvsDuration = stats.Float64("sti_find_provs_duration", "The time it took storetheindex finds from the network to succeed or fail because of timeout or completion", stats.UnitMilliseconds)
 	STIFindProvsLength   = stats.Int64("sti_find_provs_length", "Number of providers returned for successful responses", stats.UnitDimensionless)
+	STIFindProvsEmpty    = stats.Int64("sti_find_provs_empty", "Number of empty responses returned", stats.UnitDimensionless)
 
 	AWSRequests              = stats.Int64("aws_reqs", "Requests made to AWS", stats.UnitDimensionless)
 	AWSRequestDurationMillis = stats.Float64("aws_req_duration", "The time it took to make an AWS request and receive a response", stats.UnitMilliseconds)
@@ -208,6 +209,11 @@ var (
 		TagKeys:     []tag.Key{KeyName},
 		Aggregation: defaultProvidersDistribution,
 	}
+	STIFindProvsEmptyView = &view.View{
+		Measure:     STIFindProvsEmpty,
+		TagKeys:     []tag.Key{KeyName},
+		Aggregation: view.Sum(),
+	}
 	// DHT views
 	ReceivedMessagesView = &view.View{
 		Measure:     dhtmetrics.ReceivedMessages,
@@ -344,6 +350,7 @@ var DefaultViews = []*view.View{
 	STIFindProvsView,
 	STIFindProvsDurationView,
 	STIFindProvsLengthView,
+	STIFindProvsEmptyView,
 	ProviderRecordsPerKeyView,
 	PrefetchesView,
 	PrefetchDurationMillisView,

providers/reframe.go

@@ -39,6 +39,13 @@ func (x *reframeProvider) AddProvider(ctx context.Context, key []byte, prov peer
 	return fmt.Errorf("reframe does not support adding providers")
 }
 
+func emptyIndicator(x int64) int64 {
+	if x == 0 {
+		return 1
+	}
+	return 0
+}
+
 func (x *reframeProvider) GetProviders(ctx context.Context, key []byte) ([]peer.AddrInfo, error) {
 	mh, err := multihash.Cast(key)
 	if err != nil {
@@ -47,12 +54,16 @@ func (x *reframeProvider) GetProviders(ctx context.Context, key []byte) ([]peer.
 	cid1 := cid.NewCidV1(cid.Raw, mh)
 	start := time.Now()
 	peers, err := x.reframe.FindProviders(ctx, cid1)
+
 	if err != nil {
 		log.Errorf("reframe error: %s", err)
 		recordReframeFindProvsComplete(ctx, metricsErrStr(err), time.Since(start))
 	} else {
 		recordReframeFindProvsComplete(ctx, "Success", time.Since(start))
-		stats.Record(ctx, metrics.STIFindProvsLength.M(int64(len(peers))))
+		numPeers := int64(len(peers))
+		stats.Record(ctx, metrics.STIFindProvsLength.M(numPeers))
+		stats.Record(ctx, metrics.STIFindProvsEmpty.M(emptyIndicator(numPeers)))
+		fmt.Printf("numPeers: %d\n", numPeers)
 	}
 	return peers, err
 }