From 137a28d82b78ac0e1abc156d18e57b7efc08bb6e Mon Sep 17 00:00:00 2001
From: Owen Diehl <ow.diehl@gmail.com>
Date: Thu, 17 Feb 2022 10:14:07 -0500
Subject: [PATCH] Adds bytes and entries to chunk metadata in tsdb (#5414)

* adds bytes and entries to chunk metadata in tsdb

* removes comment
---
 pkg/storage/tsdb/index/chunk.go  | 11 +++++++++--
 pkg/storage/tsdb/index/index.go  | 12 ++++++++++++
 pkg/storage/tsdb/querier_test.go | 12 ++++++++++++
 3 files changed, 33 insertions(+), 2 deletions(-)

diff --git a/pkg/storage/tsdb/index/chunk.go b/pkg/storage/tsdb/index/chunk.go
index cb4cc3d45e..509b6fd4fb 100644
--- a/pkg/storage/tsdb/index/chunk.go
+++ b/pkg/storage/tsdb/index/chunk.go
@@ -4,7 +4,14 @@ package index
 type ChunkMeta struct {
 	Checksum uint32
 
-	// Time range the data covers.
-	// When MaxTime == math.MaxInt64 the chunk is still open and being appended to.
 	MinTime, MaxTime int64
+
+	// Bytes use an uint64 as an uint32 can only hold [0,4GB)
+	// While this is well within current chunk guidelines (1.5MB being "standard"),
+	// I (owen-d) prefer to overallocate here
+	// Since TSDB accesses are seeked rather than scanned, this choice
+	// should have little effect as long as there is enough memory available
+	Bytes uint64
+
+	Entries uint32
 }
diff --git a/pkg/storage/tsdb/index/index.go b/pkg/storage/tsdb/index/index.go
index 312a3fed9c..8e5a1d6e52 100644
--- a/pkg/storage/tsdb/index/index.go
+++ b/pkg/storage/tsdb/index/index.go
@@ -458,6 +458,8 @@ func (w *Writer) AddSeries(ref storage.SeriesRef, lset labels.Labels, chunks ...
 		c := chunks[0]
 		w.buf2.PutVarint64(c.MinTime)
 		w.buf2.PutUvarint64(uint64(c.MaxTime - c.MinTime))
+		w.buf2.PutUvarint64(c.Bytes)
+		w.buf2.PutUvarint32(c.Entries)
 		w.buf2.PutBE32(c.Checksum)
 		t0 := c.MaxTime
 
@@ -466,6 +468,8 @@ func (w *Writer) AddSeries(ref storage.SeriesRef, lset labels.Labels, chunks ...
 			// instead of uvarint because chunks may overlap
 			w.buf2.PutVarint64(c.MinTime - t0)
 			w.buf2.PutUvarint64(uint64(c.MaxTime - c.MinTime))
+			w.buf2.PutUvarint64(c.Bytes)
+			w.buf2.PutUvarint32(c.Entries)
 			t0 = c.MaxTime
 
 			w.buf2.PutBE32(c.Checksum)
@@ -1865,12 +1869,16 @@ func (dec *Decoder) Series(b []byte, lbls *labels.Labels, chks *[]ChunkMeta) err
 
 	t0 := d.Varint64()
 	maxt := int64(d.Uvarint64()) + t0
+	nBytes := d.Uvarint64()
+	entries := uint32(d.Uvarint64())
 	checksum := d.Be32()
 
 	*chks = append(*chks, ChunkMeta{
 		Checksum: checksum,
 		MinTime:  t0,
 		MaxTime:  maxt,
+		Bytes:    nBytes,
+		Entries:  entries,
 	})
 	t0 = maxt
 
@@ -1879,6 +1887,8 @@ func (dec *Decoder) Series(b []byte, lbls *labels.Labels, chks *[]ChunkMeta) err
 		// instead of uvarint because chunks may overlap
 		mint := d.Varint64() + t0
 		maxt := int64(d.Uvarint64()) + mint
+		nBytes := d.Uvarint64()
+		entries := uint32(d.Uvarint64())
 		checksum := d.Be32()
 		t0 = maxt
 
@@ -1890,6 +1900,8 @@ func (dec *Decoder) Series(b []byte, lbls *labels.Labels, chks *[]ChunkMeta) err
 			Checksum: checksum,
 			MinTime:  mint,
 			MaxTime:  maxt,
+			Bytes:    nBytes,
+			Entries:  entries,
 		})
 	}
 	return d.Err()
diff --git a/pkg/storage/tsdb/querier_test.go b/pkg/storage/tsdb/querier_test.go
index e010bdb25c..27a63f74b7 100644
--- a/pkg/storage/tsdb/querier_test.go
+++ b/pkg/storage/tsdb/querier_test.go
@@ -33,11 +33,15 @@ func TestQueryIndex(t *testing.T) {
 					Checksum: 1,
 					MinTime:  1,
 					MaxTime:  10,
+					Bytes:    10,
+					Entries:  10,
 				},
 				{
 					Checksum: 2,
 					MinTime:  5,
 					MaxTime:  15,
+					Bytes:    10,
+					Entries:  10,
 				},
 			},
 		},
@@ -48,11 +52,15 @@ func TestQueryIndex(t *testing.T) {
 					Checksum: 3,
 					MinTime:  20,
 					MaxTime:  30,
+					Bytes:    10,
+					Entries:  10,
 				},
 				{
 					Checksum: 4,
 					MinTime:  40,
 					MaxTime:  50,
+					Bytes:    10,
+					Entries:  10,
 				},
 			},
 		},
@@ -63,11 +71,15 @@ func TestQueryIndex(t *testing.T) {
 					Checksum: 1,
 					MinTime:  1,
 					MaxTime:  10,
+					Bytes:    10,
+					Entries:  10,
 				},
 				{
 					Checksum: 2,
 					MinTime:  5,
 					MaxTime:  15,
+					Bytes:    10,
+					Entries:  10,
 				},
 			},
 		},