Short-circuit chunk dedup in proxy

The store proxy deduplicates series by calculating a hash on the each
aggregate chunk. If at least one hash is not present in the dedup-map,
the entire series chunk is added to the response, including all aggregate
chunks.

Because of this, we can short-circuit deduping chunks and stop early if any
aggregate chunks is not previously seen.

Signed-off-by: Filip Petkovski <[email protected]>

pkg/store/proxy_heap.go

@@ -21,6 +21,7 @@ import (
 	"github.com/pkg/errors"
 	"github.com/prometheus/client_golang/prometheus"
 	"github.com/prometheus/prometheus/model/labels"
+
 	"github.com/thanos-io/thanos/pkg/store/labelpb"
 	"github.com/thanos-io/thanos/pkg/store/storepb"
 	"github.com/thanos-io/thanos/pkg/tracing"
@@ -134,8 +135,8 @@ func (d *dedupResponseHeap) At() *storepb.SeriesResponse {
 
 				if _, ok := chunkDedupMap[h]; !ok {
 					chk := chk
-
 					chunkDedupMap[h] = &chk
+					break
 				}
 			}