executor: add config EnableCollectExecutionInfo (#15493)

config/config.go

@@ -136,6 +136,8 @@ type Config struct {
 	NewCollationsEnabledOnFirstBootstrap bool `toml:"new_collations_enabled_on_first_bootstrap" json:"new_collations_enabled_on_first_bootstrap"`
 	// Experimental contains parameters for experimental features.
 	Experimental Experimental `toml:"experimental" json:"experimental"`
+	// EnableCollectExecutionInfo enables the TiDB to collect execution info.
+	EnableCollectExecutionInfo bool `toml:"enable-collect-execution-info" json:"enable-collect-execution-info"`
 }
 
 // UpdateTempStoragePath is to update the `TempStoragePath` if port/statusPort was changed
@@ -677,6 +679,7 @@ var defaultConf = Config{
 		AllowAutoRandom:       false,
 		AllowsExpressionIndex: false,
 	},
+	EnableCollectExecutionInfo: false,
 }
 
 var (

executor/builder.go

@@ -31,6 +31,7 @@ import (
 	"github.com/pingcap/parser/ast"
 	"github.com/pingcap/parser/model"
 	"github.com/pingcap/parser/mysql"
+	"github.com/pingcap/tidb/config"
 	"github.com/pingcap/tidb/distsql"
 	"github.com/pingcap/tidb/domain"
 	"github.com/pingcap/tidb/executor/aggfuncs"
@@ -97,6 +98,9 @@ type MockPhysicalPlan interface {
 }
 
 func (b *executorBuilder) build(p plannercore.Plan) Executor {
+	if config.GetGlobalConfig().EnableCollectExecutionInfo && b.ctx.GetSessionVars().StmtCtx.RuntimeStatsColl == nil {
+		b.ctx.GetSessionVars().StmtCtx.RuntimeStatsColl = execdetails.NewRuntimeStatsColl()
+	}
 	switch v := p.(type) {
 	case nil:
 		return nil
@@ -865,7 +869,9 @@ func (b *executorBuilder) buildExplain(v *plannercore.Explain) Executor {
 		explain:      v,
 	}
 	if v.Analyze {
-		b.ctx.GetSessionVars().StmtCtx.RuntimeStatsColl = execdetails.NewRuntimeStatsColl()
+		if b.ctx.GetSessionVars().StmtCtx.RuntimeStatsColl == nil {
+			b.ctx.GetSessionVars().StmtCtx.RuntimeStatsColl = execdetails.NewRuntimeStatsColl()
+		}
 		explainExec.analyzeExec = b.build(v.TargetPlan)
 	}
 	return explainExec
@@ -1986,6 +1992,10 @@ func (b *executorBuilder) constructDAGReq(plans []plannercore.PhysicalPlan) (dag
 	dagReq = &tipb.DAGRequest{}
 	dagReq.TimeZoneName, dagReq.TimeZoneOffset = timeutil.Zone(b.ctx.GetSessionVars().Location())
 	sc := b.ctx.GetSessionVars().StmtCtx
+	if sc.RuntimeStatsColl != nil {
+		collExec := true
+		dagReq.CollectExecutionSummaries = &collExec
+	}
 	dagReq.Flags = sc.PushDownFlags()
 	dagReq.Executors, streaming, err = constructDistExec(b.ctx, plans)
 
@@ -2675,10 +2685,6 @@ func (builder *dataReaderBuilder) buildTableReaderForIndexJoin(ctx context.Conte
 }
 
 func (builder *dataReaderBuilder) buildTableReaderFromHandles(ctx context.Context, e *TableReaderExecutor, handles []int64) (Executor, error) {
-	if e.runtimeStats != nil && e.dagPB.CollectExecutionSummaries == nil {
-		colExec := true
-		e.dagPB.CollectExecutionSummaries = &colExec
-	}
 	startTS, err := builder.getSnapshotTS()
 	if err != nil {
 		return nil, err

sessionctx/variable/session.go

@@ -1282,6 +1282,8 @@ func (s *SessionVars) SetSystemVar(name string, val string) error {
 		s.SelectLimit = result
 	case TiDBSlowLogMasking:
 		s.EnableSlowLogMasking = TiDBOptOn(val)
+	case TiDBEnableCollectExecutionInfo:
+		config.GetGlobalConfig().EnableCollectExecutionInfo = TiDBOptOn(val)
 	}
 	s.systems[name] = val
 	return nil

sessionctx/variable/sysvar.go

@@ -721,6 +721,7 @@ var defaultSysVars = []*SysVar{
 	{ScopeSession, TiDBCheckMb4ValueInUTF8, BoolToIntStr(config.GetGlobalConfig().CheckMb4ValueInUTF8)},
 	{ScopeSession, TiDBFoundInPlanCache, BoolToIntStr(DefTiDBFoundInPlanCache)},
 	{ScopeGlobal, TiDBSlowLogMasking, BoolToIntStr(DefTiDBSlowLogMasking)},
+	{ScopeSession, TiDBEnableCollectExecutionInfo, BoolToIntStr(DefTiDBEnableCollectExecutionInfo)},
 }
 
 // SynonymsSysVariables is synonyms of system variables.

sessionctx/variable/tidb_vars.go

@@ -393,6 +393,9 @@ const (
 
 	// TiDBSlowLogMasking indicates that whether masking the query data when log slow query.
 	TiDBSlowLogMasking = "tidb_slow_log_masking"
+
+	// TiDBEnableCollectExecutionInfo indicates that whether execution info is collected.
+	TiDBEnableCollectExecutionInfo = "tidb_enable_collect_execution_info"
 )
 
 // Default TiDB system variable values.
@@ -487,6 +490,7 @@ const (
 	DefTiDBMetricSchemaRangeDuration   = 60 // 60s
 	DefTiDBFoundInPlanCache            = false
 	DefTiDBSlowLogMasking              = false
+	DefTiDBEnableCollectExecutionInfo  = false
 )
 
 // Process global variables.

sessionctx/variable/varsutil.go

@@ -155,6 +155,8 @@ func GetSessionOnlySysVars(s *SessionVars, key string) (string, bool, error) {
 		return CapturePlanBaseline.GetVal(), true, nil
 	case TiDBFoundInPlanCache:
 		return BoolToIntStr(s.PrevFoundInPlanCache), true, nil
+	case TiDBEnableCollectExecutionInfo:
+		return BoolToIntStr(config.GetGlobalConfig().EnableCollectExecutionInfo), true, nil
 	}
 	sVal, ok := s.GetSystemVar(key)
 	if ok {
@@ -438,7 +440,7 @@ func ValidateSetSystemVar(vars *SessionVars, name string, value string, scope Sc
 		TiDBLowResolutionTSO, TiDBEnableIndexMerge, TiDBEnableNoopFuncs,
 		TiDBCheckMb4ValueInUTF8, TiDBEnableSlowLog, TiDBRecordPlanInSlowLog,
 		TiDBScatterRegion, TiDBGeneralLog, TiDBConstraintCheckInPlace,
-		TiDBEnableVectorizedExpression, TiDBFoundInPlanCache:
+		TiDBEnableVectorizedExpression, TiDBFoundInPlanCache, TiDBEnableCollectExecutionInfo:
 		fallthrough
 	case GeneralLog, AvoidTemporalUpgrade, BigTables, CheckProxyUsers, LogBin,
 		CoreFile, EndMakersInJSON, SQLLogBin, OfflineMode, PseudoSlaveMode, LowPriorityUpdates,