[chore] preallocate slice (open-telemetry#24940)

djaglowski · Aug 18, 2023 · cb6ba56 · cb6ba56
1 parent 267ce81
commit cb6ba56
Showing 1 changed file with 5 additions and 3 deletions.
diff --git a/exporter/prometheusremotewriteexporter/helper.go b/exporter/prometheusremotewriteexporter/helper.go
@@ -16,23 +16,25 @@ func batchTimeSeries(tsMap map[string]*prompb.TimeSeries, maxBatchByteSize int)
  return nil, errors.New("invalid tsMap: cannot be empty map")
  }
 
- var requests []*prompb.WriteRequest
- var tsArray []prompb.TimeSeries
+ requests := make([]*prompb.WriteRequest, 0, len(tsMap))
+ tsArray := make([]prompb.TimeSeries, 0, len(tsMap))
  sizeOfCurrentBatch := 0
 
+ i := 0
  for _, v := range tsMap {
  sizeOfSeries := v.Size()
 
  if sizeOfCurrentBatch+sizeOfSeries >= maxBatchByteSize {
  wrapped := convertTimeseriesToRequest(tsArray)
  requests = append(requests, wrapped)
 
- tsArray = nil
+ tsArray = make([]prompb.TimeSeries, 0, len(tsMap)-i)
  sizeOfCurrentBatch = 0
  }
 
  tsArray = append(tsArray, *v)
  sizeOfCurrentBatch += sizeOfSeries
+ i++
  }
 
  if len(tsArray) != 0 {