reused blocks instrumentation

Signed-off-by: Owen Diehl <[email protected]>

pkg/bloomcompactor/controller.go

@@ -346,6 +346,7 @@ func (s *SimpleBloomController) buildGaps(
 
 			// Fetch blocks that aren't up to date but are in the desired fingerprint range
 			// to try and accelerate bloom creation
+			level.Debug(logger).Log("msg", "loading series and blocks for gap", "blocks", len(gap.blocks))
 			seriesItr, blocksIter, err := s.loadWorkForGap(ctx, table, tenant, plan.tsdb, gap)
 			if err != nil {
 				level.Error(logger).Log("msg", "failed to get series and blocks", "err", err)
@@ -436,6 +437,8 @@ func (s *SimpleBloomController) buildGaps(
 
 			created = append(created, meta)
 			totalSeries += uint64(seriesItrWithCounter.Count())
+
+			s.metrics.blocksReused.Add(float64(len(gap.blocks)))
 		}
 	}
 

pkg/bloomcompactor/metrics.go

@@ -32,6 +32,8 @@ type Metrics struct {
 	tenantsCompletedTime *prometheus.HistogramVec
 	tenantsSeries        prometheus.Histogram
 
+	blocksReused prometheus.Counter
+
 	blocksCreated prometheus.Counter
 	blocksDeleted prometheus.Counter
 	metasCreated  prometheus.Counter
@@ -120,6 +122,12 @@ func NewMetrics(r prometheus.Registerer, bloomMetrics *v1.Metrics) *Metrics {
 			// Up to 10M series per tenant, way more than what we expect given our max_global_streams_per_user limits
 			Buckets: prometheus.ExponentialBucketsRange(1, 10000000, 10),
 		}),
+		blocksReused: promauto.With(r).NewCounter(prometheus.CounterOpts{
+			Namespace: metricsNamespace,
+			Subsystem: metricsSubsystem,
+			Name:      "blocks_reused_total",
+			Help:      "Number of overlapping bloom blocks reused when creating new blocks",
+		}),
 		blocksCreated: promauto.With(r).NewCounter(prometheus.CounterOpts{
 			Namespace: metricsNamespace,
 			Subsystem: metricsSubsystem,