make auto-analyze concurrency configurable

winoros · Aug 22, 2022 · 77d372a · 77d372a
1 parent 3d5577b
commit 77d372a
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Showing 3 changed files with 22 additions and 3 deletions.
diff --git a/executor/adapter.go b/executor/adapter.go
@@ -19,6 +19,7 @@ import (
 	"context"
 	"fmt"
 	"runtime/trace"
+	"strconv"
 	"strings"
 	"sync/atomic"
 	"time"
@@ -425,9 +426,19 @@ func (a *ExecStmt) Exec(ctx context.Context) (_ sqlexec.RecordSet, err error) {
 		oriScan := sctx.GetSessionVars().DistSQLScanConcurrency()
 		oriIndex := sctx.GetSessionVars().IndexSerialScanConcurrency()
 		oriIso, _ := sctx.GetSessionVars().GetSystemVar(variable.TxnIsolation)
-		terror.Log(sctx.GetSessionVars().SetSystemVar(variable.TiDBBuildStatsConcurrency, "1"))
-		sctx.GetSessionVars().SetDistSQLScanConcurrency(1)
-		sctx.GetSessionVars().SetIndexSerialScanConcurrency(1)
+		autoConcurrency, err1 := sctx.GetSessionVars().GetSessionOrGlobalSystemVar(variable.TiDBAutoBuildStatsConcurrency)
+		terror.Log(err1)
+		if err1 == nil {
+			terror.Log(sctx.GetSessionVars().SetSystemVar(variable.TiDBBuildStatsConcurrency, autoConcurrency))
+		}
+		sVal, err2 := sctx.GetSessionVars().GetSessionOrGlobalSystemVar(variable.TiDBSysProcScanConcurrency)
+		terror.Log(err2)
+		if err2 == nil {
+			concurrency, err3 := strconv.ParseInt(sVal, 10, 64)
+			terror.Log(err3)
+			sctx.GetSessionVars().SetDistSQLScanConcurrency(int(concurrency))
+			sctx.GetSessionVars().SetIndexSerialScanConcurrency(int(concurrency))
+		}
 		terror.Log(sctx.GetSessionVars().SetSystemVar(variable.TxnIsolation, ast.ReadCommitted))
 		defer func() {
 			terror.Log(sctx.GetSessionVars().SetSystemVar(variable.TiDBBuildStatsConcurrency, oriStats))

diff --git a/sessionctx/variable/sysvar.go b/sessionctx/variable/sysvar.go
@@ -854,6 +854,8 @@ var defaultSysVars = []*SysVar{
 	}, GetGlobal: func(s *SessionVars) (string, error) {
 		return BoolToOnOff(EnableTmpStorageOnOOM.Load()), nil
 	}},
+	{Scope: ScopeGlobal, Name: TiDBAutoBuildStatsConcurrency, Value: strconv.Itoa(DefAutoBuildStatsConcurrency), Type: TypeInt, MinValue: 1, MaxValue: MaxConfigurableConcurrency},
+	{Scope: ScopeGlobal, Name: TiDBSysProcScanConcurrency, Value: strconv.Itoa(DefTiDBSysProcScanConcurrency), Type: TypeInt, MinValue: 1, MaxValue: MaxConfigurableConcurrency},
 
 	/* The system variables below have GLOBAL and SESSION scope  */
 	{Scope: ScopeGlobal | ScopeSession, Name: TiDBRowFormatVersion, Value: strconv.Itoa(DefTiDBRowFormatV1), Type: TypeUnsigned, MinValue: 1, MaxValue: 2, SetGlobal: func(s *SessionVars, val string) error {

diff --git a/sessionctx/variable/tidb_vars.go b/sessionctx/variable/tidb_vars.go
@@ -791,6 +791,10 @@ const (
 	TiDBDDLEnableFastReorg = "tidb_ddl_fast_reorg"
 	// TiDBDDLDiskQuota used to set disk quota for lightning add index.
 	TiDBDDLDiskQuota = "tidb_ddl_disk_quota"
+	// TiDBAutoBuildStatsConcurrency is used to set the build concurrency of auto-analyze.
+	TiDBAutoBuildStatsConcurrency = "tidb_auto_build_stats_concurrency"
+	// TiDBSysProcScanConcurrency is used to set the scan concurrency of for backend system processes, like auto-analyze.
+	TiDBSysProcScanConcurrency = "tidb_sysproc_scan_concurrency"
 )
 
 // TiDB intentional limits
@@ -1007,6 +1011,8 @@ const (
 	DefTiDBEnableFastReorg                         = false
 	DefTiDBDDLEnableFastReorg                      = false
 	DefTiDBDDLDiskQuota                            = 100 * 1024 * 1024 * 1024 // 100GB
+	DefAutoBuildStatsConcurrency                   = 1
+	DefTiDBSysProcScanConcurrency                  = 1
 )
 
 // Process global variables.