func()

in v1storage/series.go [204:247]

• 28 lines of code
• 9 McCabe index (conditional complexity)

func (s *memorySeries) add(v model.SamplePair) (int, error) {
	if len(s.chunkDescs) == 0 || s.headChunkClosed {
		newHead := chunk.NewDesc(chunk.New(), v.Timestamp)
		s.chunkDescs = append(s.chunkDescs, newHead)
		s.headChunkClosed = false
	} else if s.headChunkUsedByIterator && s.head().RefCount() > 1 {
		// We only need to clone the head chunk if the current head
		// chunk was used in an iterator at all and if the refCount is
		// still greater than the 1 we always have because the head
		// chunk is not yet persisted. The latter is just an
		// approximation. We will still clone unnecessarily if an older
		// iterator using a previous version of the head chunk is still
		// around and keep the head chunk pinned. We needed to track
		// pins by version of the head chunk, which is probably not
		// worth the effort.
		chunk.Ops.WithLabelValues(chunk.Clone).Inc()
		// No locking needed here because a non-persisted head chunk can
		// not get evicted concurrently.
		s.head().C = s.head().C.Clone()
		s.headChunkUsedByIterator = false
	}

	chunks, err := s.head().Add(v)
	if err != nil {
		return 0, err
	}
	s.head().C = chunks[0]

	for _, c := range chunks[1:] {
		s.chunkDescs = append(s.chunkDescs, chunk.NewDesc(c, c.FirstTime()))
	}

	// Populate lastTime of now-closed chunks.
	for _, cd := range s.chunkDescs[len(s.chunkDescs)-len(chunks) : len(s.chunkDescs)-1] {
		if err := cd.MaybePopulateLastTime(); err != nil {
			return 0, err
		}
	}

	s.lastTime = v.Timestamp
	s.lastSampleValue = v.Value
	s.lastSampleValueSet = true
	return len(chunks) - 1, nil
}