ingester: Fix regression on usage of cortex_ingester_queried_chunks

Fixes: #6396

Signed-off-by: Charlie Le <[email protected]>

Author: CharlieTLe

pkg/ingester/ingester.go

@@ -1968,18 +1968,21 @@ func (i *Ingester) QueryStream(req *client.QueryRequest, stream client.Ingester_
 	numSamples := 0
 	numSeries := 0
 	totalDataBytes := 0
-	numSeries, numSamples, totalDataBytes, err = i.queryStreamChunks(ctx, db, int64(from), int64(through), matchers, shardMatcher, stream)
+	numChunks := 0
+	numSeries, numSamples, totalDataBytes, numChunks, err = i.queryStreamChunks(ctx, db, int64(from), int64(through), matchers, shardMatcher, stream)
 
 	if err != nil {
 		return err
 	}
 
 	i.metrics.queriedSeries.Observe(float64(numSeries))
 	i.metrics.queriedSamples.Observe(float64(numSamples))
-	level.Debug(spanlog).Log("series", numSeries, "samples", numSamples, "data_bytes", totalDataBytes)
+	i.metrics.queriedChunks.Observe(float64(numChunks))
+	level.Debug(spanlog).Log("series", numSeries, "samples", numSamples, "data_bytes", totalDataBytes, "chunks", numChunks)
 	spanlog.SetTag("series", numSeries)
 	spanlog.SetTag("samples", numSamples)
 	spanlog.SetTag("data_bytes", totalDataBytes)
+	spanlog.SetTag("chunks", numChunks)
 	return nil
 }
 
@@ -1998,16 +2001,16 @@ func (i *Ingester) trackInflightQueryRequest() (func(), error) {
 }
 
 // queryStreamChunks streams metrics from a TSDB. This implements the client.IngesterServer interface
-func (i *Ingester) queryStreamChunks(ctx context.Context, db *userTSDB, from, through int64, matchers []*labels.Matcher, sm *storepb.ShardMatcher, stream client.Ingester_QueryStreamServer) (numSeries, numSamples, totalBatchSizeBytes int, _ error) {
+func (i *Ingester) queryStreamChunks(ctx context.Context, db *userTSDB, from, through int64, matchers []*labels.Matcher, sm *storepb.ShardMatcher, stream client.Ingester_QueryStreamServer) (numSeries, numSamples, totalBatchSizeBytes, numChunks int, _ error) {
 	q, err := db.ChunkQuerier(from, through)
 	if err != nil {
-		return 0, 0, 0, err
+		return 0, 0, 0, 0, err
 	}
 	defer q.Close()
 
 	c, err := i.trackInflightQueryRequest()
 	if err != nil {
-		return 0, 0, 0, err
+		return 0, 0, 0, 0, err
 	}
 	hints := &storage.SelectHints{
 		Start:           from,
@@ -2018,7 +2021,7 @@ func (i *Ingester) queryStreamChunks(ctx context.Context, db *userTSDB, from, th
 	ss := q.Select(ctx, false, hints, matchers...)
 	c()
 	if ss.Err() != nil {
-		return 0, 0, 0, ss.Err()
+		return 0, 0, 0, 0, ss.Err()
 	}
 
 	chunkSeries := make([]client.TimeSeriesChunk, 0, queryStreamBatchSize)
@@ -2044,7 +2047,7 @@ func (i *Ingester) queryStreamChunks(ctx context.Context, db *userTSDB, from, th
 			// It is not guaranteed that chunk returned by iterator is populated.
 			// For now just return error. We could also try to figure out how to read the chunk.
 			if meta.Chunk == nil {
-				return 0, 0, 0, errors.Errorf("unfilled chunk returned from TSDB chunk querier")
+				return 0, 0, 0, 0, errors.Errorf("unfilled chunk returned from TSDB chunk querier")
 			}
 
 			ch := client.Chunk{
@@ -2061,10 +2064,11 @@ func (i *Ingester) queryStreamChunks(ctx context.Context, db *userTSDB, from, th
 			case chunkenc.EncFloatHistogram:
 				ch.Encoding = int32(encoding.PrometheusFloatHistogramChunk)
 			default:
-				return 0, 0, 0, errors.Errorf("unknown chunk encoding from TSDB chunk querier: %v", meta.Chunk.Encoding())
+				return 0, 0, 0, 0, errors.Errorf("unknown chunk encoding from TSDB chunk querier: %v", meta.Chunk.Encoding())
 			}
 
 			ts.Chunks = append(ts.Chunks, ch)
+			numChunks++
 			numSamples += meta.Chunk.NumSamples()
 		}
 		numSeries++
@@ -2078,7 +2082,7 @@ func (i *Ingester) queryStreamChunks(ctx context.Context, db *userTSDB, from, th
 				Chunkseries: chunkSeries,
 			})
 			if err != nil {
-				return 0, 0, 0, err
+				return 0, 0, 0, 0, err
 			}
 
 			batchSizeBytes = 0
@@ -2091,7 +2095,7 @@ func (i *Ingester) queryStreamChunks(ctx context.Context, db *userTSDB, from, th
 
 	// Ensure no error occurred while iterating the series set.
 	if err := ss.Err(); err != nil {
-		return 0, 0, 0, err
+		return 0, 0, 0, 0, err
 	}
 
 	// Final flush any existing metrics
@@ -2100,11 +2104,11 @@ func (i *Ingester) queryStreamChunks(ctx context.Context, db *userTSDB, from, th
 			Chunkseries: chunkSeries,
 		})
 		if err != nil {
-			return 0, 0, 0, err
+			return 0, 0, 0, 0, err
 		}
 	}
 
-	return numSeries, numSamples, totalBatchSizeBytes, nil
+	return numSeries, numSamples, totalBatchSizeBytes, numChunks, nil
 }
 
 func (i *Ingester) getTSDB(userID string) *userTSDB {

pkg/ingester/ingester_test.go

@@ -3087,7 +3087,8 @@ func TestIngester_QueryStreamManySamplesChunks(t *testing.T) {
 	// Create ingester.
 	cfg := defaultIngesterTestConfig(t)
 
-	i, err := prepareIngesterWithBlocksStorage(t, cfg, prometheus.NewRegistry())
+	reg := prometheus.NewRegistry()
+	i, err := prepareIngesterWithBlocksStorage(t, cfg, reg)
 	require.NoError(t, err)
 	require.NoError(t, services.StartAndAwaitRunning(context.Background(), i))
 	defer services.StopAndAwaitTerminated(context.Background(), i) //nolint:errcheck
@@ -3154,6 +3155,7 @@ func TestIngester_QueryStreamManySamplesChunks(t *testing.T) {
 	recvMsgs := 0
 	series := 0
 	totalSamples := 0
+	totalChunks := 0
 
 	for {
 		resp, err := s.Recv()
@@ -3174,6 +3176,7 @@ func TestIngester_QueryStreamManySamplesChunks(t *testing.T) {
 				require.NoError(t, err)
 				totalSamples += chk.NumSamples()
 			}
+			totalChunks += len(ts.Chunks)
 		}
 	}
 
@@ -3183,6 +3186,21 @@ func TestIngester_QueryStreamManySamplesChunks(t *testing.T) {
 	require.True(t, 2 <= recvMsgs && recvMsgs <= 3)
 	require.Equal(t, 3, series)
 	require.Equal(t, 100000+500000+samplesCount, totalSamples)
+	require.Equal(t, 13335, totalChunks)
+	require.NoError(t, testutil.GatherAndCompare(reg, bytes.NewBufferString(`
+		# HELP cortex_ingester_queried_chunks The total number of chunks returned from queries.
+		# TYPE cortex_ingester_queried_chunks histogram
+		cortex_ingester_queried_chunks_bucket{le="10"} 0
+		cortex_ingester_queried_chunks_bucket{le="80"} 0
+		cortex_ingester_queried_chunks_bucket{le="640"} 0
+		cortex_ingester_queried_chunks_bucket{le="5120"} 0
+		cortex_ingester_queried_chunks_bucket{le="40960"} 1
+		cortex_ingester_queried_chunks_bucket{le="327680"} 1
+		cortex_ingester_queried_chunks_bucket{le="2.62144e+06"} 1
+		cortex_ingester_queried_chunks_bucket{le="+Inf"} 1
+		cortex_ingester_queried_chunks_sum 13335
+		cortex_ingester_queried_chunks_count 1
+	`), `cortex_ingester_queried_chunks`))
 }
 
 func writeRequestSingleSeries(lbls labels.Labels, samples []cortexpb.Sample) *cortexpb.WriteRequest {