topsql: make topsql enable only be controlled by pub/sub sink

domain/sysvar_cache.go

@@ -202,8 +202,6 @@ func (do *Domain) checkEnableServerGlobalVar(name, sVal string) {
 		err = stmtsummary.StmtSummaryByDigestMap.SetMaxSQLLength(sVal, false)
 	case variable.TiDBCapturePlanBaseline:
 		variable.CapturePlanBaseline.Set(sVal, false)
-	case variable.TiDBEnableTopSQL:
-		topsqlstate.GlobalState.Enable.Store(variable.TiDBOptOn(sVal))
 	case variable.TiDBTopSQLPrecisionSeconds:
 		var val int64
 		val, err = strconv.ParseInt(sVal, 10, 64)

executor/executor_test.go

@@ -8765,7 +8765,7 @@ func (s *testResourceTagSuite) TestResourceGroupTag(c *C) {
 	tbInfo := testGetTableByName(c, tk.Se, "test", "t")
 
 	// Enable Top SQL
-	topsqlstate.GlobalState.Enable.Store(true)
+	topsqlstate.EnableTopSQL()
 	config.UpdateGlobal(func(conf *config.Config) {
 		conf.TopSQL.ReceiverAddress = "mock-agent"
 	})

executor/set_test.go

@@ -1539,10 +1539,8 @@ func (s *testSerialSuite) TestSetTopSQLVariables(c *C) {
 	tk := testkit.NewTestKit(c, s.store)
 	tk.MustExec("set @@global.tidb_enable_top_sql='On';")
 	tk.MustQuery("select @@global.tidb_enable_top_sql;").Check(testkit.Rows("1"))
-	c.Assert(topsqlstate.GlobalState.Enable.Load(), IsTrue)
 	tk.MustExec("set @@global.tidb_enable_top_sql='off';")
 	tk.MustQuery("select @@global.tidb_enable_top_sql;").Check(testkit.Rows("0"))
-	c.Assert(topsqlstate.GlobalState.Enable.Load(), IsFalse)
 
 	tk.MustExec("set @@global.tidb_top_sql_precision_seconds=2;")
 	tk.MustQuery("select @@global.tidb_top_sql_precision_seconds;").Check(testkit.Rows("2"))

server/tidb_test.go

@@ -1299,7 +1299,6 @@ func TestTopSQLCPUProfile(t *testing.T) {
 	dbt.MustExec("create table t (a int auto_increment, b int, unique index idx(a));")
 	dbt.MustExec("create table t1 (a int auto_increment, b int, unique index idx(a));")
 	dbt.MustExec("create table t2 (a int auto_increment, b int, unique index idx(a));")
-	dbt.MustExec("set @@global.tidb_enable_top_sql='On';")
 	config.UpdateGlobal(func(conf *config.Config) {
 		conf.TopSQL.ReceiverAddress = "127.0.0.1:4001"
 	})
@@ -1544,11 +1543,10 @@ func TestTopSQLStatementStats(t *testing.T) {
 	dbt.MustExec("create table t3 (a int, b int, unique index idx(a));")
 
 	// Enable TopSQL
-	topsqlstate.GlobalState.Enable.Store(true)
+	topsqlstate.EnableTopSQL()
 	config.UpdateGlobal(func(conf *config.Config) {
 		conf.TopSQL.ReceiverAddress = "mock-agent"
 	})
-	dbt.MustExec("set @@global.tidb_enable_top_sql='On';")
 
 	const ExecCountPerSQL = 3
 

sessionctx/variable/sysvar.go

@@ -1246,12 +1246,9 @@ var defaultSysVars = []*SysVar{
 		return nil
 	}},
 	// variable for top SQL feature.
-	{Scope: ScopeGlobal, Name: TiDBEnableTopSQL, Value: BoolToOnOff(topsqlstate.DefTiDBTopSQLEnable), Type: TypeBool, Hidden: true, AllowEmpty: true, GetGlobal: func(s *SessionVars) (string, error) {
-		return BoolToOnOff(topsqlstate.GlobalState.Enable.Load()), nil
-	}, SetGlobal: func(vars *SessionVars, s string) error {
-		topsqlstate.GlobalState.Enable.Store(TiDBOptOn(s))
-		return nil
-	}, GlobalConfigName: GlobalConfigEnableTopSQL},
+	// TopSQL enable only be controlled by TopSQL pub/sub sinker.
+	// This global variable only uses to update the global config which store in PD(ETCD).
+	{Scope: ScopeGlobal, Name: TiDBEnableTopSQL, Value: BoolToOnOff(topsqlstate.DefTiDBTopSQLEnable), Type: TypeBool, AllowEmpty: true, GlobalConfigName: GlobalConfigEnableTopSQL},
 	{Scope: ScopeGlobal, Name: TiDBTopSQLPrecisionSeconds, Value: strconv.Itoa(topsqlstate.DefTiDBTopSQLPrecisionSeconds), Type: TypeInt, Hidden: true, MinValue: 1, MaxValue: math.MaxInt64, GetGlobal: func(s *SessionVars) (string, error) {
 		return strconv.FormatInt(topsqlstate.GlobalState.PrecisionSeconds.Load(), 10), nil
 	}, SetGlobal: func(vars *SessionVars, s string) error {

util/topsql/state/state.go

@@ -27,7 +27,7 @@ const (
 
 // GlobalState is the global Top-SQL state.
 var GlobalState = State{
-	Enable:                atomic.NewBool(DefTiDBTopSQLEnable),
+	enable:                atomic.NewBool(false),
 	PrecisionSeconds:      atomic.NewInt64(DefTiDBTopSQLPrecisionSeconds),
 	MaxStatementCount:     atomic.NewInt64(DefTiDBTopSQLMaxStatementCount),
 	MaxCollect:            atomic.NewInt64(DefTiDBTopSQLMaxCollect),
@@ -36,8 +36,8 @@ var GlobalState = State{
 
 // State is the state for control top sql feature.
 type State struct {
-	// Enable top-sql or not.
-	Enable *atomic.Bool
+	// enable top-sql or not.
+	enable *atomic.Bool
 	// The refresh interval of top-sql.
 	PrecisionSeconds *atomic.Int64
 	// The maximum number of statements kept in memory.
@@ -50,15 +50,15 @@ type State struct {
 
 // EnableTopSQL enables the top SQL feature.
 func EnableTopSQL() {
-	GlobalState.Enable.Store(true)
+	GlobalState.enable.Store(true)
 }
 
 // DisableTopSQL disables the top SQL feature.
 func DisableTopSQL() {
-	GlobalState.Enable.Store(false)
+	GlobalState.enable.Store(false)
 }
 
 // TopSQLEnabled uses to check whether enabled the top SQL feature.
 func TopSQLEnabled() bool {
-	return GlobalState.Enable.Load()
+	return GlobalState.enable.Load()
 }