ttl: Implement scan and delete task for TTL

sessionctx/variable/sysvar.go

@@ -2127,6 +2127,45 @@ var defaultSysVars = []*SysVar{
 			s.EnableReuseCheck = TiDBOptOn(val)
 			return nil
 		}},
+	{Scope: ScopeGlobal, Name: TiDBTTLJobEnable, Value: BoolToOnOff(DefTiDBTTLJobEnable), Type: TypeBool, SetGlobal: func(ctx context.Context, vars *SessionVars, s string) error {
+		EnableTTLJob.Store(TiDBOptOn(s))
+		return nil
+	}, GetGlobal: func(ctx context.Context, vars *SessionVars) (string, error) {
+		return BoolToOnOff(EnableTTLJob.Load()), nil
+	}},
+	{Scope: ScopeGlobal, Name: TiDBTTLScanBatchSize, Value: strconv.Itoa(DefTiDBTTLScanBatchSize), Type: TypeInt, MinValue: DefTiDBTTLScanBatchMinSize, MaxValue: DefTiDBTTLScanBatchMaxSize, SetGlobal: func(ctx context.Context, vars *SessionVars, s string) error {
+		val, err := strconv.ParseInt(s, 10, 64)
+		if err != nil {
+			return err
+		}
+		TTLScanBatchSize.Store(val)
+		return nil
+	}, GetGlobal: func(ctx context.Context, vars *SessionVars) (string, error) {
+		val := TTLScanBatchSize.Load()
+		return strconv.FormatInt(val, 10), nil
+	}},
+	{Scope: ScopeGlobal, Name: TiDBTTLDeleteBatchSize, Value: strconv.Itoa(DefTiDBTTLDeleteBatchSize), Type: TypeInt, MinValue: DefTiDBTTLDeleteBatchMinSize, MaxValue: DefTiDBTTLDeleteBatchMaxSize, SetGlobal: func(ctx context.Context, vars *SessionVars, s string) error {
+		val, err := strconv.ParseInt(s, 10, 64)
+		if err != nil {
+			return err
+		}
+		TTLDeleteBatchSize.Store(val)
+		return nil
+	}, GetGlobal: func(ctx context.Context, vars *SessionVars) (string, error) {
+		val := TTLDeleteBatchSize.Load()
+		return strconv.FormatInt(val, 10), nil
+	}},
+	{Scope: ScopeGlobal, Name: TiDBTTLDeleteRateLimit, Value: strconv.Itoa(DefTiDBTTLDeleteRateLimit), Type: TypeInt, MinValue: 0, MaxValue: math.MaxInt64, SetGlobal: func(ctx context.Context, vars *SessionVars, s string) error {
+		val, err := strconv.ParseInt(s, 10, 64)
+		if err != nil {
+			return err
+		}
+		TTLDeleteRateLimit.Store(val)
+		return nil
+	}, GetGlobal: func(ctx context.Context, vars *SessionVars) (string, error) {
+		val := TTLDeleteRateLimit.Load()
+		return strconv.FormatInt(val, 10), nil
+	}},
 	{
 		Scope: ScopeGlobal | ScopeSession, Name: TiDBStoreBatchSize, Value: strconv.FormatInt(DefTiDBStoreBatchSize, 10),
 		Type: TypeInt, MinValue: 0, MaxValue: 25000, SetSession: func(s *SessionVars, val string) error {

sessionctx/variable/tidb_vars.go

@@ -868,6 +868,14 @@ const (
 	TiDBGOGCTunerThreshold = "tidb_gogc_tuner_threshold"
 	// TiDBExternalTS is the ts to read through when the `TiDBEnableExternalTsRead` is on
 	TiDBExternalTS = "tidb_external_ts"
+	// TiDBTTLJobEnable is used to enable/disable scheduling ttl job
+	TiDBTTLJobEnable = "tidb_ttl_job_enable"
+	// TiDBTTLScanBatchSize is used to control the batch size in the SELECT statement for TTL jobs
+	TiDBTTLScanBatchSize = "tidb_ttl_scan_batch_size"
+	// TiDBTTLDeleteBatchSize is used to control the batch size in the DELETE statement for TTL jobs
+	TiDBTTLDeleteBatchSize = "tidb_ttl_delete_batch_size"
+	// TiDBTTLDeleteRateLimit is used to control the delete rate limit for TTL jobs in each node
+	TiDBTTLDeleteRateLimit = "tidb_ttl_delete_rate_limit"
 	// PasswordReuseHistory limit a few passwords to reuse.
 	PasswordReuseHistory = "password_history"
 	// PasswordReuseTime limit how long passwords can be reused.
@@ -1115,6 +1123,14 @@ const (
 	DefTiDBUseAlloc                                  = false
 	DefTiDBEnablePlanReplayerCapture                 = false
 	DefTiDBIndexMergeIntersectionConcurrency         = ConcurrencyUnset
+	DefTiDBTTLJobEnable                              = true
+	DefTiDBTTLScanBatchSize                          = 500
+	DefTiDBTTLScanBatchMaxSize                       = 10240
+	DefTiDBTTLScanBatchMinSize                       = 1
+	DefTiDBTTLDeleteBatchSize                        = 500
+	DefTiDBTTLDeleteBatchMaxSize                     = 10240
+	DefTiDBTTLDeleteBatchMinSize                     = 1
+	DefTiDBTTLDeleteRateLimit                        = 0
 	DefPasswordReuseHistory                          = 0
 	DefPasswordReuseTime                             = 0
 	DefTiDBStoreBatchSize                            = 0
@@ -1180,6 +1196,10 @@ var (
 	PasswordValidationMixedCaseCount   = atomic.NewInt32(1)
 	PasswordValidtaionNumberCount      = atomic.NewInt32(1)
 	PasswordValidationSpecialCharCount = atomic.NewInt32(1)
+	EnableTTLJob                       = atomic.NewBool(DefTiDBTTLJobEnable)
+	TTLScanBatchSize                   = atomic.NewInt64(DefTiDBTTLScanBatchSize)
+	TTLDeleteBatchSize                 = atomic.NewInt64(DefTiDBTTLDeleteBatchSize)
+	TTLDeleteRateLimit                 = atomic.NewInt64(DefTiDBTTLDeleteRateLimit)
 	PasswordHistory                    = atomic.NewInt64(DefPasswordReuseHistory)
 	PasswordReuseInterval              = atomic.NewInt64(DefPasswordReuseTime)
 	IsSandBoxModeEnabled               = atomic.NewBool(false)

ttl/cache/table.go

@@ -56,6 +56,8 @@ func getTableKeyColumns(tbl *model.TableInfo) ([]*model.ColumnInfo, []*types.Fie
 
 // PhysicalTable is used to provide some information for a physical table in TTL job
 type PhysicalTable struct {
+	// ID is the physical ID of the table
+	ID int64
 	// Schema is the database name of the table
 	Schema model.CIStr
 	*model.TableInfo
@@ -92,11 +94,13 @@ func NewPhysicalTable(schema model.CIStr, tbl *model.TableInfo, partition model.
 		return nil, err
 	}
 
+	var physicalID int64
 	var partitionDef *model.PartitionDefinition
 	if tbl.Partition == nil {
 		if partition.L != "" {
 			return nil, errors.Errorf("table '%s.%s' is not a partitioned table", schema, tbl.Name)
 		}
+		physicalID = tbl.ID
 	} else {
 		if partition.L == "" {
 			return nil, errors.Errorf("partition name is required, table '%s.%s' is a partitioned table", schema, tbl.Name)
@@ -112,9 +116,12 @@ func NewPhysicalTable(schema model.CIStr, tbl *model.TableInfo, partition model.
 		if partitionDef == nil {
 			return nil, errors.Errorf("partition '%s' is not found in ttl table '%s.%s'", partition.O, schema, tbl.Name)
 		}
+
+		physicalID = partitionDef.ID
 	}
 
 	return &PhysicalTable{
+		ID:             physicalID,
 		Schema:         schema,
 		TableInfo:      tbl,
 		Partition:      partition,

ttl/cache/table_test.go

@@ -110,7 +110,7 @@ func TestNewTTLTable(t *testing.T) {
 			physicalTbls = append(physicalTbls, ttlTbl)
 		} else {
 			for _, partition := range tblInfo.Partition.Definitions {
-				ttlTbl, err := cache.NewPhysicalTable(model.NewCIStr(c.db), tblInfo, model.NewCIStr(partition.Name.O))
+				ttlTbl, err := cache.NewPhysicalTable(model.NewCIStr(c.db), tblInfo, partition.Name)
 				if c.timeCol == "" {
 					require.Error(t, err)
 					continue
@@ -131,10 +131,12 @@ func TestNewTTLTable(t *testing.T) {
 			require.Same(t, timeColumn, ttlTbl.TimeColumn)
 
 			if tblInfo.Partition == nil {
+				require.Equal(t, ttlTbl.TableInfo.ID, ttlTbl.ID)
 				require.Equal(t, "", ttlTbl.Partition.L)
 				require.Nil(t, ttlTbl.PartitionDef)
 			} else {
 				def := tblInfo.Partition.Definitions[i]
+				require.Equal(t, def.ID, ttlTbl.ID)
 				require.Equal(t, def.Name.L, ttlTbl.Partition.L)
 				require.Equal(t, def, *(ttlTbl.PartitionDef))
 			}

ttl/session/BUILD.bazel

@@ -10,6 +10,7 @@ go_library(
         "//kv",
         "//parser/terror",
         "//sessionctx",
+        "//sessionctx/variable",
         "//sessiontxn",
         "//util/chunk",
         "//util/sqlexec",
@@ -22,10 +23,12 @@ go_test(
     srcs = [
         "main_test.go",
         "session_test.go",
+        "sysvar_test.go",
     ],
-    embed = [":session"],
     flaky = True,
     deps = [
+        ":session",
+        "//sessionctx/variable",
         "//testkit",
         "//testkit/testsetup",
         "@com_github_pingcap_errors//:errors",

ttl/session/session.go

@@ -22,6 +22,7 @@ import (
 	"github.com/pingcap/tidb/kv"
 	"github.com/pingcap/tidb/parser/terror"
 	"github.com/pingcap/tidb/sessionctx"
+	"github.com/pingcap/tidb/sessionctx/variable"
 	"github.com/pingcap/tidb/sessiontxn"
 	"github.com/pingcap/tidb/util/chunk"
 	"github.com/pingcap/tidb/util/sqlexec"
@@ -36,6 +37,8 @@ type Session interface {
 	ExecuteSQL(ctx context.Context, sql string, args ...interface{}) ([]chunk.Row, error)
 	// RunInTxn executes the specified function in a txn
 	RunInTxn(ctx context.Context, fn func() error) (err error)
+	// ResetWithGlobalTimeZone resets the session time zone to global time zone
+	ResetWithGlobalTimeZone(ctx context.Context) error
 	// Close closes the session
 	Close()
 }
@@ -112,6 +115,27 @@ func (s *session) RunInTxn(ctx context.Context, fn func() error) (err error) {
 	return err
 }
 
+// ResetWithGlobalTimeZone resets the session time zone to global time zone
+func (s *session) ResetWithGlobalTimeZone(ctx context.Context) error {
+	sessVar := s.GetSessionVars()
+	globalTZ, err := sessVar.GetGlobalSystemVar(ctx, variable.TimeZone)
+	if err != nil {
+		return err
+	}
+
+	tz, err := sessVar.GetSessionOrGlobalSystemVar(ctx, variable.TimeZone)
+	if err != nil {
+		return err
+	}
+
+	if globalTZ == tz {
+		return nil
+	}
+
+	_, err = s.ExecuteSQL(ctx, "SET @@time_zone=@@global.time_zone")
+	return err
+}
+
 // Close closes the session
 func (s *session) Close() {
 	if s.closeFn != nil {

ttl/session/session_test.go

@@ -12,14 +12,15 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-package session
+package session_test
 
 import (
 	"context"
 	"testing"
 
 	"github.com/pingcap/errors"
 	"github.com/pingcap/tidb/testkit"
+	"github.com/pingcap/tidb/ttl/session"
 	"github.com/stretchr/testify/require"
 )
 
@@ -28,7 +29,7 @@ func TestSessionRunInTxn(t *testing.T) {
 	tk := testkit.NewTestKit(t, store)
 	tk.MustExec("use test")
 	tk.MustExec("create table t(id int primary key, v int)")
-	se := NewSession(tk.Session(), tk.Session(), nil)
+	se := session.NewSession(tk.Session(), tk.Session(), nil)
 	tk2 := testkit.NewTestKit(t, store)
 	tk2.MustExec("use test")
 
@@ -50,3 +51,15 @@ func TestSessionRunInTxn(t *testing.T) {
 	}))
 	tk2.MustQuery("select * from t order by id asc").Check(testkit.Rows("1 10", "3 30"))
 }
+
+func TestSessionResetTimeZone(t *testing.T) {
+	store := testkit.CreateMockStore(t)
+	tk := testkit.NewTestKit(t, store)
+	tk.MustExec("set @@global.time_zone='UTC'")
+	tk.MustExec("set @@time_zone='Asia/Shanghai'")
+
+	se := session.NewSession(tk.Session(), tk.Session(), nil)
+	tk.MustQuery("select @@time_zone").Check(testkit.Rows("Asia/Shanghai"))
+	require.NoError(t, se.ResetWithGlobalTimeZone(context.TODO()))
+	tk.MustQuery("select @@time_zone").Check(testkit.Rows("UTC"))
+}

ttl/session/sysvar_test.go

@@ -0,0 +1,125 @@
+// 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 session_test
+
+import (
+	"fmt"
+	"strconv"
+	"testing"
+
+	"github.com/pingcap/tidb/sessionctx/variable"
+	"github.com/pingcap/tidb/testkit"
+	"github.com/stretchr/testify/require"
+)
+
+func TestSysVarTTLJobEnable(t *testing.T) {
+	origEnableDDL := variable.EnableTTLJob.Load()
+	defer func() {
+		variable.EnableTTLJob.Store(origEnableDDL)
+	}()
+
+	store := testkit.CreateMockStore(t)
+	tk := testkit.NewTestKit(t, store)
+	tk.MustExec("set @@global.tidb_ttl_job_enable=0")
+	require.False(t, variable.EnableTTLJob.Load())
+	tk.MustQuery("select @@global.tidb_ttl_job_enable").Check(testkit.Rows("0"))
+	tk.MustQuery("select @@tidb_ttl_job_enable").Check(testkit.Rows("0"))
+
+	tk.MustExec("set @@global.tidb_ttl_job_enable=1")
+	require.True(t, variable.EnableTTLJob.Load())
+	tk.MustQuery("select @@global.tidb_ttl_job_enable").Check(testkit.Rows("1"))
+	tk.MustQuery("select @@tidb_ttl_job_enable").Check(testkit.Rows("1"))
+
+	tk.MustExec("set @@global.tidb_ttl_job_enable=0")
+	require.False(t, variable.EnableTTLJob.Load())
+	tk.MustQuery("select @@global.tidb_ttl_job_enable").Check(testkit.Rows("0"))
+	tk.MustQuery("select @@tidb_ttl_job_enable").Check(testkit.Rows("0"))
+}
+
+func TestSysVarTTLScanBatchSize(t *testing.T) {
+	origScanBatchSize := variable.TTLScanBatchSize.Load()
+	defer func() {
+		variable.TTLScanBatchSize.Store(origScanBatchSize)
+	}()
+
+	store := testkit.CreateMockStore(t)
+	tk := testkit.NewTestKit(t, store)
+	tk.MustExec("set @@global.tidb_ttl_scan_batch_size=789")
+	require.Equal(t, int64(789), variable.TTLScanBatchSize.Load())
+	tk.MustQuery("select @@global.tidb_ttl_scan_batch_size").Check(testkit.Rows("789"))
+	tk.MustQuery("select @@tidb_ttl_scan_batch_size").Check(testkit.Rows("789"))
+
+	tk.MustExec("set @@global.tidb_ttl_scan_batch_size=0")
+	require.Equal(t, int64(1), variable.TTLScanBatchSize.Load())
+	tk.MustQuery("select @@global.tidb_ttl_scan_batch_size").Check(testkit.Rows("1"))
+	tk.MustQuery("select @@tidb_ttl_scan_batch_size").Check(testkit.Rows("1"))
+
+	maxVal := int64(variable.DefTiDBTTLScanBatchMaxSize)
+	tk.MustExec(fmt.Sprintf("set @@global.tidb_ttl_scan_batch_size=%d", maxVal+1))
+	require.Equal(t, maxVal, variable.TTLScanBatchSize.Load())
+	tk.MustQuery("select @@global.tidb_ttl_scan_batch_size").Check(testkit.Rows(strconv.FormatInt(maxVal, 10)))
+	tk.MustQuery("select @@tidb_ttl_scan_batch_size").Check(testkit.Rows(strconv.FormatInt(maxVal, 10)))
+}
+
+func TestSysVarTTLScanDeleteBatchSize(t *testing.T) {
+	origScanBatchSize := variable.TTLScanBatchSize.Load()
+	defer func() {
+		variable.TTLScanBatchSize.Store(origScanBatchSize)
+	}()
+
+	store := testkit.CreateMockStore(t)
+	tk := testkit.NewTestKit(t, store)
+	tk.MustExec("set @@global.tidb_ttl_delete_batch_size=789")
+	require.Equal(t, int64(789), variable.TTLDeleteBatchSize.Load())
+	tk.MustQuery("select @@global.tidb_ttl_delete_batch_size").Check(testkit.Rows("789"))
+	tk.MustQuery("select @@tidb_ttl_delete_batch_size").Check(testkit.Rows("789"))
+
+	tk.MustExec("set @@global.tidb_ttl_delete_batch_size=0")
+	require.Equal(t, int64(1), variable.TTLDeleteBatchSize.Load())
+	tk.MustQuery("select @@global.tidb_ttl_delete_batch_size").Check(testkit.Rows("1"))
+	tk.MustQuery("select @@tidb_ttl_delete_batch_size").Check(testkit.Rows("1"))
+
+	maxVal := int64(variable.DefTiDBTTLDeleteBatchMaxSize)
+	tk.MustExec(fmt.Sprintf("set @@global.tidb_ttl_delete_batch_size=%d", maxVal+1))
+	require.Equal(t, maxVal, variable.TTLDeleteBatchSize.Load())
+	tk.MustQuery("select @@global.tidb_ttl_delete_batch_size").Check(testkit.Rows(strconv.FormatInt(maxVal, 10)))
+	tk.MustQuery("select @@tidb_ttl_delete_batch_size").Check(testkit.Rows(strconv.FormatInt(maxVal, 10)))
+}
+
+func TestSysVarTTLScanDeleteLimit(t *testing.T) {
+	origDeleteLimit := variable.TTLDeleteRateLimit.Load()
+	defer func() {
+		variable.TTLDeleteRateLimit.Store(origDeleteLimit)
+	}()
+
+	store := testkit.CreateMockStore(t)
+	tk := testkit.NewTestKit(t, store)
+	tk.MustQuery("select @@global.tidb_ttl_delete_rate_limit").Check(testkit.Rows("0"))
+
+	tk.MustExec("set @@global.tidb_ttl_delete_rate_limit=100000")
+	require.Equal(t, int64(100000), variable.TTLDeleteRateLimit.Load())
+	tk.MustQuery("select @@global.tidb_ttl_delete_rate_limit").Check(testkit.Rows("100000"))
+	tk.MustQuery("select @@tidb_ttl_delete_rate_limit").Check(testkit.Rows("100000"))
+
+	tk.MustExec("set @@global.tidb_ttl_delete_rate_limit=0")
+	require.Equal(t, int64(0), variable.TTLDeleteRateLimit.Load())
+	tk.MustQuery("select @@global.tidb_ttl_delete_rate_limit").Check(testkit.Rows("0"))
+	tk.MustQuery("select @@tidb_ttl_delete_rate_limit").Check(testkit.Rows("0"))
+
+	tk.MustExec("set @@global.tidb_ttl_delete_rate_limit=-1")
+	require.Equal(t, int64(0), variable.TTLDeleteRateLimit.Load())
+	tk.MustQuery("select @@global.tidb_ttl_delete_rate_limit").Check(testkit.Rows("0"))
+	tk.MustQuery("select @@tidb_ttl_delete_rate_limit").Check(testkit.Rows("0"))
+}