Address a review comment

Signed-off-by: 🌲 Harry 🌊 John 🏔 <johrry@amazon.com>

Author: harry671003

docs/configuration/config-file-reference.md

@@ -2681,8 +2681,9 @@ The `limits_config` configures default and per-tenant limits imposed by Cortex s
 [max_fetched_chunk_bytes_per_query: <int> | default = 0]
 
 # The maximum combined size of all data that a query can fetch from each
-# ingester and storage. This limit is enforced in the querier and ruler only
-# when running Cortex with blocks storage. 0 to disable.
+# ingester and storage. This limit is only applied for `query`, `query_range`
+# and `series` APIs. This limit is enforced in the querier and ruler only when
+# running Cortex with blocks storage. 0 to disable.
 # CLI flag: -querier.max-fetched-data-bytes-per-query
 [max_fetched_data_bytes_per_query: <int> | default = 0]
 

pkg/distributor/distributor.go

@@ -1027,11 +1027,11 @@ func (d *Distributor) MetricsForLabelMatchers(ctx context.Context, from, through
 			if err != nil {
 				return nil, err
 			}
+			if err := queryLimiter.AddDataBytes(resp.Size()); err != nil {
+				return nil, err
+			}
 			ms := ingester_client.FromMetricsForLabelMatchersResponse(resp)
 			for _, m := range ms {
-				if err := queryLimiter.AddDataBytes(resp.Size()); err != nil {
-					return nil, err
-				}
 				if err := queryLimiter.AddSeries(cortexpb.FromMetricsToLabelAdapters(m)); err != nil {
 					return nil, err
 				}
@@ -1058,6 +1058,9 @@ func (d *Distributor) MetricsForLabelMatchersStream(ctx context.Context, from, t
 			defer stream.CloseSend() //nolint:errcheck
 			for {
 				resp, err := stream.Recv()
+				if err := queryLimiter.AddDataBytes(resp.Size()); err != nil {
+					return nil, err
+				}
 
 				if err == io.EOF {
 					break
@@ -1068,9 +1071,6 @@ func (d *Distributor) MetricsForLabelMatchersStream(ctx context.Context, from, t
 				for _, metric := range resp.Metric {
 					m := cortexpb.FromLabelAdaptersToMetricWithCopy(metric.Labels)
 
-					if err := queryLimiter.AddDataBytes(resp.Size()); err != nil {
-						return nil, err
-					}
 					if err := queryLimiter.AddSeries(metric.Labels); err != nil {
 						return nil, err
 					}

pkg/querier/blocks_store_queryable.go

@@ -691,8 +691,7 @@ func (q *blocksStoreQuerier) fetchSeriesFromStores(
 
 			numSeries := len(mySeries)
 			chunkBytes := countChunkBytes(mySeries...)
-			labelBytes := countDataBytes(mySeries...)
-			dataBytes := labelBytes + chunkBytes
+			dataBytes := countDataBytes(mySeries...)
 
 			reqStats.AddFetchedSeries(uint64(numSeries))
 			reqStats.AddFetchedChunkBytes(uint64(chunkBytes))
@@ -1008,7 +1007,7 @@ func countChunkBytes(series ...*storepb.Series) (count int) {
 	return count
 }
 
-// countChunkBytes returns the size of the chunks making up the provided series in bytes
+// countDataBytes returns the combined size of the all series
 func countDataBytes(series ...*storepb.Series) (count int) {
 	for _, s := range series {
 		count += s.Size()

pkg/util/limiter/query_limiter.go

@@ -102,7 +102,7 @@ func (ql *QueryLimiter) AddChunkBytes(chunkSizeInBytes int) error {
 	return nil
 }
 
-// AddDataBytes adds the input label size in bytes and returns an error if the limit is reached.
+// AddDataBytes adds the queried data bytes and returns an error if the limit is reached.
 func (ql *QueryLimiter) AddDataBytes(dataSizeInBytes int) error {
 	if ql.maxDataBytesPerQuery == 0 {
 		return nil

pkg/util/validation/limits.go

@@ -152,7 +152,7 @@ func (l *Limits) RegisterFlags(f *flag.FlagSet) {
 	f.IntVar(&l.MaxChunksPerQuery, "querier.max-fetched-chunks-per-query", 2000000, "Maximum number of chunks that can be fetched in a single query from ingesters and long-term storage. This limit is enforced in the querier, ruler and store-gateway. 0 to disable.")
 	f.IntVar(&l.MaxFetchedSeriesPerQuery, "querier.max-fetched-series-per-query", 0, "The maximum number of unique series for which a query can fetch samples from each ingesters and blocks storage. This limit is enforced in the querier only when running Cortex with blocks storage. 0 to disable")
 	f.IntVar(&l.MaxFetchedChunkBytesPerQuery, "querier.max-fetched-chunk-bytes-per-query", 0, "Deprecated (user max-fetched-data-bytes-per-query instead): The maximum size of all chunks in bytes that a query can fetch from each ingester and storage. This limit is enforced in the querier and ruler only when running Cortex with blocks storage. 0 to disable.")
-	f.IntVar(&l.MaxFetchedDataBytesPerQuery, "querier.max-fetched-data-bytes-per-query", 0, "The maximum combined size of all data that a query can fetch from each ingester and storage. This limit is enforced in the querier and ruler only when running Cortex with blocks storage. 0 to disable.")
+	f.IntVar(&l.MaxFetchedDataBytesPerQuery, "querier.max-fetched-data-bytes-per-query", 0, "The maximum combined size of all data that a query can fetch from each ingester and storage. This limit is only applied for `query`, `query_range` and `series` APIs. This limit is enforced in the querier and ruler only when running Cortex with blocks storage. 0 to disable.")
 	f.Var(&l.MaxQueryLength, "store.max-query-length", "Limit the query time range (end - start time). This limit is enforced in the query-frontend (on the received query) and in the querier (on the query possibly split by the query-frontend). 0 to disable.")
 	f.Var(&l.MaxQueryLookback, "querier.max-query-lookback", "Limit how long back data (series and metadata) can be queried, up until <lookback> duration ago. This limit is enforced in the query-frontend, querier and ruler. If the requested time range is outside the allowed range, the request will not fail but will be manipulated to only query data within the allowed time range. 0 to disable.")
 	f.IntVar(&l.MaxQueryParallelism, "querier.max-query-parallelism", 14, "Maximum number of split queries will be scheduled in parallel by the frontend.")