test: add a memory usage test for real-tikv-test

tests/realtikvtest/addindextest/failpoints_test.go

@@ -25,7 +25,9 @@ func initTestFailpoint(t *testing.T) *suiteContext {
 }
 
 func TestFailpointsCreateNonUniqueIndex(t *testing.T) {
-	t.Skip()
+	if !*FullMode {
+		t.Skip()
+	}
 	var colIDs = [][]int{
 		{1, 4, 7, 10, 13, 16, 19, 22, 25},
 		{2, 5, 8, 11, 14, 17, 20, 23, 26},
@@ -36,7 +38,9 @@ func TestFailpointsCreateNonUniqueIndex(t *testing.T) {
 }
 
 func TestFailpointsCreateUniqueIndex(t *testing.T) {
-	t.Skip()
+	if !*FullMode {
+		t.Skip()
+	}
 	var colIDs = [][]int{
 		{1, 6, 7, 8, 11, 13, 15, 16, 18, 19, 22, 26},
 		{2, 9, 11, 17},
@@ -47,19 +51,25 @@ func TestFailpointsCreateUniqueIndex(t *testing.T) {
 }
 
 func TestFailpointsCreatePrimaryKeyFailpoints(t *testing.T) {
-	t.Skip()
+	if !*FullMode {
+		t.Skip()
+	}
 	ctx := initTest(t)
 	testOneIndexFrame(ctx, 0, addIndexPK)
 }
 
 func TestFailpointsCreateGenColIndex(t *testing.T) {
-	t.Skip()
+	if !*FullMode {
+		t.Skip()
+	}
 	ctx := initTestFailpoint(t)
 	testOneIndexFrame(ctx, 29, addIndexGenCol)
 }
 
 func TestFailpointsCreateMultiColsIndex(t *testing.T) {
-	t.Skip()
+	if !*FullMode {
+		t.Skip()
+	}
 	var coliIDs = [][]int{
 		{1, 4, 7},
 		{2, 5, 8},

tests/realtikvtest/addindextest/memory_test.go

@@ -0,0 +1,53 @@
+// Copyright 2022 PingCAP, Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package addindextest
+
+import (
+	"fmt"
+	"strings"
+	"testing"
+
+	"github.com/pingcap/tidb/ddl/ingest"
+	"github.com/pingcap/tidb/testkit"
+	"github.com/pingcap/tidb/tests/realtikvtest"
+	"github.com/stretchr/testify/require"
+)
+
+func TestLitAddIndexMemoryUsage(t *testing.T) {
+	store := realtikvtest.CreateMockStoreAndSetup(t)
+	tk := testkit.NewTestKit(t, store)
+	tk.MustExec("drop database if exists addindexlit;")
+	tk.MustExec("create database addindexlit;")
+	tk.MustExec("use addindexlit;")
+	tk.MustExec(`set global tidb_ddl_enable_fast_reorg=on;`)
+
+	tk.MustExec("create table t (a int, b int, c int);")
+	var sb strings.Builder
+	sb.WriteString("insert into t values ")
+	size := 100
+	for i := 0; i < size; i++ {
+		sb.WriteString(fmt.Sprintf("(%d, %d, %d)", i, i, i))
+		if i != size-1 {
+			sb.WriteString(",")
+		}
+	}
+	sb.WriteString(";")
+	tk.MustExec(sb.String())
+	require.Equal(t, int64(0), ingest.LitMemRoot.CurrentUsage())
+	tk.MustExec("alter table t add index idx(a);")
+	tk.MustExec("alter table t add unique index idx1(b);")
+	tk.MustExec("admin check table t;")
+	require.Equal(t, int64(0), ingest.LitMemRoot.CurrentUsage())
+}