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pingcap · Jun 7, 2022 · 271a46b · 271a46b
1 parent 90ffaf2
commit 271a46b
Showing 1 changed file with 1 addition and 0 deletions.
diff --git a/executor/join.go b/executor/join.go
@@ -95,6 +95,7 @@ type HashJoinExec struct {
 
 	stats *hashJoinRuntimeStats
 
+	// We pre-alloc and reuse the Rows and RowPtrs for each probe goroutine, to avoid allocation frequently
 	buildSideRows    [][]chunk.Row
 	buildSideRowPtrs [][]chunk.RowPtr
 }