TSDB: metrics for queries (#1981)

* Update queriedSeries and queriedSamples metrics in v2Query.

Signed-off-by: Peter Štibraný <[email protected]>

* Increment number of users when creating new TSDB.

Signed-off-by: Peter Štibraný <[email protected]>

* Use length of slices to update metrics.

Signed-off-by: Peter Štibraný <[email protected]>

* Update CHANGELOG.md

Signed-off-by: Peter Štibraný <[email protected]>

* Removed memUsers.Inc() in favor of PR #1982.

Signed-off-by: Peter Štibraný <[email protected]>

* Removed mention of cortex_ingester_memory_users from CHANGELOG.md

Signed-off-by: Peter Štibraný <[email protected]>

* One more small fix to CHANGELOG.md.

Signed-off-by: Peter Štibraný <[email protected]>

Author: pstibrany

CHANGELOG.md

@@ -30,6 +30,7 @@
 * [BUGFIX] TSDB: Fixed error handling in the series to chunks conversion with the experimental TSDB blocks storage. #1837
 * [BUGFIX] TSDB: Fixed TSDB creation conflict with blocks transfer in a `JOINING` ingester with the experimental TSDB blocks storage. #1818
 * [BUGFIX] TSDB: `experimental.tsdb.ship-interval` of <=0 treated as disabled instead of allowing panic. #1975
+* [BUGFIX] TSDB: Fixed `cortex_ingester_queried_samples` and `cortex_ingester_queried_series` metrics when using block storage. #1981
 
 ## 0.4.0 / 2019-12-02
 

pkg/ingester/ingester_v2.go

@@ -198,6 +198,8 @@ func (i *Ingester) v2Query(ctx old_ctx.Context, req *client.QueryRequest) (*clie
 		return nil, err
 	}
 
+	numSamples := 0
+
 	result := &client.QueryResponse{}
 	for ss.Next() {
 		series := ss.At()
@@ -212,9 +214,13 @@ func (i *Ingester) v2Query(ctx old_ctx.Context, req *client.QueryRequest) (*clie
 			ts.Samples = append(ts.Samples, client.Sample{Value: v, TimestampMs: t})
 		}
 
+		numSamples += len(ts.Samples)
 		result.Timeseries = append(result.Timeseries, ts)
 	}
 
+	i.metrics.queriedSeries.Observe(float64(len(result.Timeseries)))
+	i.metrics.queriedSamples.Observe(float64(numSamples))
+
 	return result, ss.Err()
 }