executor: reuse chunk for GetMatchedRowsAndPtrs calls (#48090) (#48103)

close #48082
pingcap · Nov 3, 2023 · 9e55944 · 9e55944
1 parent b7f909c
commit 9e55944
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Showing 2 changed files with 12 additions and 3 deletions.
diff --git a/executor/benchmark_test.go b/executor/benchmark_test.go
@@ -1130,6 +1130,16 @@ func BenchmarkHashJoinExec(b *testing.B) {
  b.Run(fmt.Sprintf("%v", cas), func(b *testing.B) {
  benchmarkHashJoinExecWithCase(b, cas)
  })
+
+ cols = []*types.FieldType{
+ types.NewFieldType(mysql.TypeLonglong),
+ }
+ cas = defaultHashJoinTestCase(cols, 0, false)
+ cas.keyIdx = []int{0}
+ cas.disk = true
+ b.Run(fmt.Sprintf("%v", cas), func(b *testing.B) {
+ benchmarkHashJoinExecWithCase(b, cas)
+ })
 }
 
 func BenchmarkOuterHashJoinExec(b *testing.B) {

diff --git a/executor/hash_table.go b/executor/hash_table.go
@@ -243,11 +243,10 @@ func (c *hashRowContainer) GetMatchedRowsAndPtrs(probeKey uint64, probeRow chunk
  // Some variables used for memTracker.
  var (
  matchedDataSize = int64(cap(matched))*rowSize + int64(cap(matchedPtrs))*rowPtrSize
- lastChunkBufPointer *chunk.Chunk = nil
+ lastChunkBufPointer *chunk.Chunk = c.chkBuf
  memDelta int64 = 0
  needTrackMemUsage = cap(innerPtrs) > signalCheckpointForJoinMask
  )
- c.chkBuf = nil
  c.memTracker.Consume(-c.chkBufSizeForOneProbe)
  if needTrackMemUsage {
  c.memTracker.Consume(int64(cap(innerPtrs)) * rowPtrSize)
@@ -265,7 +264,7 @@ func (c *hashRowContainer) GetMatchedRowsAndPtrs(probeKey uint64, probeRow chunk
  if err != nil {
  return nil, nil, err
  }
- if needTrackMemUsage && c.chkBuf != lastChunkBufPointer && lastChunkBufPointer != nil {
+ if c.chkBuf != lastChunkBufPointer && lastChunkBufPointer != nil {
  lastChunkSize := lastChunkBufPointer.MemoryUsage()
  c.chkBufSizeForOneProbe += lastChunkSize
  memDelta += lastChunkSize