Do not use syncPool for chunks when querying

block.go

@@ -118,6 +118,9 @@ type ChunkReader interface {
 	// Chunk returns the series data chunk with the given reference.
 	Chunk(ref uint64) (chunkenc.Chunk, error)
 
+	// Put will return a chunk back to a backing pool.
+	Put(chk chunkenc.Chunk)
+
 	// Close releases all underlying resources of the reader.
 	Close() error
 }

block_test.go

@@ -21,6 +21,7 @@ import (
 	"testing"
 
 	"github.com/go-kit/kit/log"
+	"github.com/prometheus/tsdb/chunkenc"
 	"github.com/prometheus/tsdb/index"
 	"github.com/prometheus/tsdb/labels"
 	"github.com/prometheus/tsdb/testutil"
@@ -105,15 +106,16 @@ func createPopulatedBlock(tb testing.TB, dir string, nSeries int, mint, maxt int
 		testutil.Ok(tb, err)
 	}
 
-	compactor, err := NewLeveledCompactor(nil, log.NewNopLogger(), []int64{1000000}, nil)
+	pool := chunkenc.NewPool()
+	compactor, err := NewLeveledCompactor(nil, log.NewNopLogger(), []int64{1000000}, pool)
 	testutil.Ok(tb, err)
 
 	testutil.Ok(tb, os.MkdirAll(dir, 0777))
 
 	ulid, err := compactor.Write(dir, head, head.MinTime(), head.MaxTime(), nil)
 	testutil.Ok(tb, err)
 
-	blk, err := OpenBlock(filepath.Join(dir, ulid.String()), nil)
+	blk, err := OpenBlock(filepath.Join(dir, ulid.String()), pool)
 	testutil.Ok(tb, err)
 	return blk
 }

chunks/chunks.go

@@ -310,9 +310,6 @@ func newReader(bs []ByteSlice, cs []io.Closer, pool chunkenc.Pool) (*Reader, err
 
 // NewReader returns a new chunk reader against the given byte slices.
 func NewReader(bs []ByteSlice, pool chunkenc.Pool) (*Reader, error) {
-	if pool == nil {
-		pool = chunkenc.NewPool()
-	}
 	return newReader(bs, nil, pool)
 }
 
@@ -323,9 +320,6 @@ func NewDirReader(dir string, pool chunkenc.Pool) (*Reader, error) {
 	if err != nil {
 		return nil, err
 	}
-	if pool == nil {
-		pool = chunkenc.NewPool()
-	}
 
 	var bs []ByteSlice
 	var cs []io.Closer
@@ -368,9 +362,18 @@ func (s *Reader) Chunk(ref uint64) (chunkenc.Chunk, error) {
 	}
 	r = b.Range(off+n, off+n+int(l))
 
+	if s.pool == nil {
+		return chunkenc.FromData(chunkenc.Encoding(r[0]), r[1:1+l])
+	}
 	return s.pool.Get(chunkenc.Encoding(r[0]), r[1:1+l])
 }
 
+func (s *Reader) Put(chk chunkenc.Chunk) {
+	if s.pool != nil && chk != nil {
+		s.pool.Put(chk)
+	}
+}
+
 func nextSequenceFile(dir string) (string, int, error) {
 	names, err := fileutil.ReadDir(dir)
 	if err != nil {

head.go

@@ -973,6 +973,10 @@ func (h *headChunkReader) Close() error {
 	return nil
 }
 
+func (h *headChunkReader) Put(_ chunkenc.Chunk) {
+	// This is a noop.
+}
+
 // packChunkID packs a seriesID and a chunkID within it into a global 8 byte ID.
 // It panicks if the seriesID exceeds 5 bytes or the chunk ID 3 bytes.
 func packChunkID(seriesID, chunkID uint64) uint64 {

querier.go

@@ -633,6 +633,10 @@ func (s *populatedChunkSeries) Next() bool {
 			continue
 		}
 
+		for _, chk := range s.chks {
+			s.chunks.Put(chk.Chunk)
+		}
+
 		s.lset = lset
 		s.chks = chks
 		s.intervals = dranges

querier_test.go

@@ -1331,6 +1331,10 @@ func (cr mockChunkReader) Chunk(id uint64) (chunkenc.Chunk, error) {
 	return nil, errors.New("Chunk with ref not found")
 }
 
+func (cr mockChunkReader) Put(_ chunkenc.Chunk) {
+	// this is a noop.
+}
+
 func (cr mockChunkReader) Close() error {
 	return nil
 }