From 2ede6a35b83832b149ba5ce026680a18e9518ee7 Mon Sep 17 00:00:00 2001
From: crazycs <crazycs520@gmail.com>
Date: Mon, 21 Feb 2022 15:37:42 +0800
Subject: [PATCH] topsql: make unit test stable (#32463)

close pingcap/tidb#32461
---
 util/topsql/topsql_test.go | 47 +++++++++++++++++++++-----------------
 1 file changed, 26 insertions(+), 21 deletions(-)

diff --git a/util/topsql/topsql_test.go b/util/topsql/topsql_test.go
index c19c48eb77eac..401ae47820ed8 100644
--- a/util/topsql/topsql_test.go
+++ b/util/topsql/topsql_test.go
@@ -124,7 +124,6 @@ func TestTopSQLReporter(t *testing.T) {
 	defer wg.Wait()
 	ctx, cancel := context.WithCancel(context.Background())
 	defer cancel()
-
 	sqlMap := make(map[string]string)
 	sql2plan := make(map[string]string)
 	recordsCnt := server.RecordsCnt()
@@ -144,29 +143,35 @@ func TestTopSQLReporter(t *testing.T) {
 			}
 		})
 	}
-	server.WaitCollectCnt(recordsCnt, 1, time.Second*5)
-	records := server.GetLatestRecords()
 	checkSQLPlanMap := map[string]struct{}{}
-	for _, req := range records {
-		require.Greater(t, len(req.Items), 0)
-		require.Greater(t, req.Items[0].CpuTimeMs, uint32(0))
-		sqlMeta, exist := server.GetSQLMetaByDigestBlocking(req.SqlDigest, time.Second)
-		require.True(t, exist)
-		expectedNormalizedSQL, exist := sqlMap[string(req.SqlDigest)]
-		require.True(t, exist)
-		require.Equal(t, expectedNormalizedSQL, sqlMeta.NormalizedSql)
-
-		expectedNormalizedPlan := sql2plan[expectedNormalizedSQL]
-		if expectedNormalizedPlan == "" || len(req.PlanDigest) == 0 {
-			require.Len(t, req.PlanDigest, 0)
-			continue
+	for retry := 0; retry < 5; retry++ {
+		server.WaitCollectCnt(recordsCnt, 1, time.Second*5)
+		records := server.GetLatestRecords()
+		for _, req := range records {
+			require.Greater(t, len(req.Items), 0)
+			require.Greater(t, req.Items[0].CpuTimeMs, uint32(0))
+			sqlMeta, exist := server.GetSQLMetaByDigestBlocking(req.SqlDigest, time.Second)
+			require.True(t, exist)
+			expectedNormalizedSQL, exist := sqlMap[string(req.SqlDigest)]
+			require.True(t, exist)
+			require.Equal(t, expectedNormalizedSQL, sqlMeta.NormalizedSql)
+
+			expectedNormalizedPlan := sql2plan[expectedNormalizedSQL]
+			if expectedNormalizedPlan == "" || len(req.PlanDigest) == 0 {
+				require.Len(t, req.PlanDigest, 0)
+				checkSQLPlanMap[expectedNormalizedSQL] = struct{}{}
+				continue
+			}
+			normalizedPlan, exist := server.GetPlanMetaByDigestBlocking(req.PlanDigest, time.Second)
+			require.True(t, exist)
+			require.Equal(t, expectedNormalizedPlan, normalizedPlan)
+			checkSQLPlanMap[expectedNormalizedSQL] = struct{}{}
+		}
+		if len(checkSQLPlanMap) == len(reqs) {
+			break
 		}
-		normalizedPlan, exist := server.GetPlanMetaByDigestBlocking(req.PlanDigest, time.Second)
-		require.True(t, exist)
-		require.Equal(t, expectedNormalizedPlan, normalizedPlan)
-		checkSQLPlanMap[expectedNormalizedSQL] = struct{}{}
 	}
-	require.Equal(t, 2, len(checkSQLPlanMap))
+	require.Equal(t, len(reqs), len(checkSQLPlanMap))
 }
 
 func TestMaxSQLAndPlanTest(t *testing.T) {