Fix values chunks_fetched_duration metric

This commit fixes the chunks_fetch_duration metric in store gateway.

Signed-off-by: Filip Petkovski <filip.petkovsky@gmail.com>

pkg/store/bucket.go

@@ -926,7 +926,7 @@ func (b *blockSeriesClient) Recv() (*storepb.SeriesResponse, error) {
 
 	if len(b.entries) == 0 {
 		if b.chunkr != nil {
-			b.chunkFetchDuration.Observe(float64(b.chunkr.stats.ChunksFetchDurationSum))
+			b.chunkFetchDuration.Observe(b.chunkr.stats.ChunksFetchDurationSum.Seconds())
 		}
 		return nil, io.EOF
 	}
@@ -2790,6 +2790,9 @@ func (r *bucketChunkReader) load(ctx context.Context, res []seriesEntry, aggrs [
 // This data range covers chunks starting at supplied offsets.
 func (r *bucketChunkReader) loadChunks(ctx context.Context, res []seriesEntry, aggrs []storepb.Aggr, seq int, part Part, pIdxs []loadIdx, calculateChunkChecksum bool, bytesLimiter BytesLimiter) error {
 	fetchBegin := time.Now()
+	defer func() {
+		r.stats.ChunksFetchDurationSum += time.Since(fetchBegin)
+	}()
 
 	// Get a reader for the required range.
 	reader, err := r.block.chunkRangeReader(ctx, seq, int64(part.Start), int64(part.End-part.Start))
@@ -2810,7 +2813,6 @@ func (r *bucketChunkReader) loadChunks(ctx context.Context, res []seriesEntry, a
 
 	r.stats.chunksFetchCount++
 	r.stats.chunksFetched += len(pIdxs)
-	r.stats.ChunksFetchDurationSum += time.Since(fetchBegin)
 	r.stats.ChunksFetchedSizeSum += units.Base2Bytes(int(part.End - part.Start))
 
 	var (
@@ -2899,7 +2901,6 @@ func (r *bucketChunkReader) loadChunks(ctx context.Context, res []seriesEntry, a
 		locked = true
 
 		r.stats.chunksFetchCount++
-		r.stats.ChunksFetchDurationSum += time.Since(fetchBegin)
 		r.stats.ChunksFetchedSizeSum += units.Base2Bytes(len(*nb))
 		err = populateChunk(&(res[pIdx.seriesEntry].chks[pIdx.chunk]), rawChunk((*nb)[n:]), aggrs, r.save, calculateChunkChecksum)
 		if err != nil {