tidb domain 源码
tidb domain 代码
文件路径：/domain/domain.go
// Copyright 2015 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 domain
import (
"context"
"fmt"
"math/rand"
"strconv"
"strings"
"sync"
"sync/atomic"
"time"
"unsafe"
"github.com/ngaut/pools"
"github.com/pingcap/errors"
"github.com/pingcap/failpoint"
"github.com/pingcap/kvproto/pkg/metapb"
"github.com/pingcap/log"
"github.com/pingcap/tidb/bindinfo"
"github.com/pingcap/tidb/br/pkg/streamhelper"
"github.com/pingcap/tidb/config"
"github.com/pingcap/tidb/ddl"
"github.com/pingcap/tidb/ddl/placement"
"github.com/pingcap/tidb/ddl/schematracker"
ddlutil "github.com/pingcap/tidb/ddl/util"
"github.com/pingcap/tidb/domain/globalconfigsync"
"github.com/pingcap/tidb/domain/infosync"
"github.com/pingcap/tidb/errno"
"github.com/pingcap/tidb/infoschema"
"github.com/pingcap/tidb/infoschema/perfschema"
"github.com/pingcap/tidb/kv"
"github.com/pingcap/tidb/meta"
"github.com/pingcap/tidb/metrics"
"github.com/pingcap/tidb/owner"
"github.com/pingcap/tidb/parser/ast"
"github.com/pingcap/tidb/parser/model"
"github.com/pingcap/tidb/parser/mysql"
"github.com/pingcap/tidb/parser/terror"
"github.com/pingcap/tidb/privilege/privileges"
"github.com/pingcap/tidb/sessionctx"
"github.com/pingcap/tidb/sessionctx/sessionstates"
"github.com/pingcap/tidb/sessionctx/variable"
"github.com/pingcap/tidb/statistics/handle"
"github.com/pingcap/tidb/telemetry"
"github.com/pingcap/tidb/types"
"github.com/pingcap/tidb/util"
"github.com/pingcap/tidb/util/dbterror"
"github.com/pingcap/tidb/util/domainutil"
"github.com/pingcap/tidb/util/engine"
"github.com/pingcap/tidb/util/expensivequery"
"github.com/pingcap/tidb/util/logutil"
"github.com/pingcap/tidb/util/sqlexec"
"github.com/tikv/client-go/v2/txnkv/transaction"
pd "github.com/tikv/pd/client"
clientv3 "go.etcd.io/etcd/client/v3"
"go.etcd.io/etcd/client/v3/concurrency"
atomicutil "go.uber.org/atomic"
"go.uber.org/zap"
"google.golang.org/grpc"
"google.golang.org/grpc/keepalive"
)
// NewMockDomain is only used for test
func NewMockDomain() *Domain {
do := &Domain{
infoCache: infoschema.NewCache(1),
}
do.infoCache.Insert(infoschema.MockInfoSchema(nil), 1)
return do
}
// Domain represents a storage space. Different domains can use the same database name.
// Multiple domains can be used in parallel without synchronization.
type Domain struct {
store kv.Storage
infoCache *infoschema.InfoCache
privHandle *privileges.Handle
bindHandle *bindinfo.BindHandle
statsHandle unsafe.Pointer
statsLease time.Duration
ddl ddl.DDL
info *infosync.InfoSyncer
globalCfgSyncer *globalconfigsync.GlobalConfigSyncer
m sync.Mutex
SchemaValidator SchemaValidator
sysSessionPool *sessionPool
exit chan struct{}
etcdClient *clientv3.Client
sysVarCache sysVarCache // replaces GlobalVariableCache
slowQuery *topNSlowQueries
expensiveQueryHandle *expensivequery.Handle
wg util.WaitGroupWrapper
statsUpdating atomicutil.Int32
cancel context.CancelFunc
indexUsageSyncLease time.Duration
dumpFileGcChecker *dumpFileGcChecker
expiredTimeStamp4PC types.Time
logBackupAdvancer *streamhelper.AdvancerDaemon
serverID uint64
serverIDSession *concurrency.Session
isLostConnectionToPD atomicutil.Int32 // !0: true, 0: false.
onClose func()
sysExecutorFactory func(*Domain) (pools.Resource, error)
sysProcesses SysProcesses
mdlCheckTableInfo *mdlCheckTableInfo
}
type mdlCheckTableInfo struct {
mu sync.Mutex
newestVer int64
jobsVerMap map[int64]int64
jobsIdsMap map[int64]string
}
// InfoCache export for test.
func (do *Domain) InfoCache() *infoschema.InfoCache {
return do.infoCache
}
// EtcdClient export for test.
func (do *Domain) EtcdClient() *clientv3.Client {
return do.etcdClient
}
// loadInfoSchema loads infoschema at startTS.
// It returns:
// 1. the needed infoschema
// 2. cache hit indicator
// 3. currentSchemaVersion(before loading)
// 4. the changed table IDs if it is not full load
// 5. an error if any
func (do *Domain) loadInfoSchema(startTS uint64) (infoschema.InfoSchema, bool, int64, *transaction.RelatedSchemaChange, error) {
snapshot := do.store.GetSnapshot(kv.NewVersion(startTS))
m := meta.NewSnapshotMeta(snapshot)
neededSchemaVersion, err := m.GetSchemaVersionWithNonEmptyDiff()
if err != nil {
return nil, false, 0, nil, err
}
if is := do.infoCache.GetByVersion(neededSchemaVersion); is != nil {
return is, true, 0, nil, nil
}
currentSchemaVersion := int64(0)
if oldInfoSchema := do.infoCache.GetLatest(); oldInfoSchema != nil {
currentSchemaVersion = oldInfoSchema.SchemaMetaVersion()
}
// TODO: tryLoadSchemaDiffs has potential risks of failure. And it becomes worse in history reading cases.
// It is only kept because there is no alternative diff/partial loading solution.
// And it is only used to diff upgrading the current latest infoschema, if:
// 1. Not first time bootstrap loading, which needs a full load.
// 2. It is newer than the current one, so it will be "the current one" after this function call.
// 3. There are less 100 diffs.
startTime := time.Now()
if currentSchemaVersion != 0 && neededSchemaVersion > currentSchemaVersion && neededSchemaVersion-currentSchemaVersion < 100 {
is, relatedChanges, err := do.tryLoadSchemaDiffs(m, currentSchemaVersion, neededSchemaVersion)
if err == nil {
do.infoCache.Insert(is, startTS)
logutil.BgLogger().Info("diff load InfoSchema success",
zap.Int64("currentSchemaVersion", currentSchemaVersion),
zap.Int64("neededSchemaVersion", neededSchemaVersion),
zap.Duration("start time", time.Since(startTime)),
zap.Int64s("phyTblIDs", relatedChanges.PhyTblIDS),
zap.Uint64s("actionTypes", relatedChanges.ActionTypes))
return is, false, currentSchemaVersion, relatedChanges, nil
}
// We can fall back to full load, don't need to return the error.
logutil.BgLogger().Error("failed to load schema diff", zap.Error(err))
}
schemas, err := do.fetchAllSchemasWithTables(m)
if err != nil {
return nil, false, currentSchemaVersion, nil, err
}
policies, err := do.fetchPolicies(m)
if err != nil {
return nil, false, currentSchemaVersion, nil, err
}
newISBuilder, err := infoschema.NewBuilder(do.Store(), do.sysFacHack).InitWithDBInfos(schemas, policies, neededSchemaVersion)
if err != nil {
return nil, false, currentSchemaVersion, nil, err
}
logutil.BgLogger().Info("full load InfoSchema success",
zap.Int64("currentSchemaVersion", currentSchemaVersion),
zap.Int64("neededSchemaVersion", neededSchemaVersion),
zap.Duration("start time", time.Since(startTime)))
is := newISBuilder.Build()
do.infoCache.Insert(is, startTS)
return is, false, currentSchemaVersion, nil, nil
}
func (do *Domain) sysFacHack() (pools.Resource, error) {
// TODO: Here we create new sessions with sysFac in DDL,
// which will use `do` as Domain instead of call `domap.Get`.
// That's because `domap.Get` requires a lock, but before
// we initialize Domain finish, we can't require that again.
// After we remove the lazy logic of creating Domain, we
// can simplify code here.
return do.sysExecutorFactory(do)
}
func (do *Domain) fetchPolicies(m *meta.Meta) ([]*model.PolicyInfo, error) {
allPolicies, err := m.ListPolicies()
if err != nil {
return nil, err
}
return allPolicies, nil
}
func (do *Domain) fetchAllSchemasWithTables(m *meta.Meta) ([]*model.DBInfo, error) {
allSchemas, err := m.ListDatabases()
if err != nil {
return nil, err
}
splittedSchemas := do.splitForConcurrentFetch(allSchemas)
doneCh := make(chan error, len(splittedSchemas))
for _, schemas := range splittedSchemas {
go do.fetchSchemasWithTables(schemas, m, doneCh)
}
for range splittedSchemas {
err = <-doneCh
if err != nil {
return nil, err
}
}
return allSchemas, nil
}
// fetchSchemaConcurrency controls the goroutines to load schemas, but more goroutines
// increase the memory usage when calling json.Unmarshal(), which would cause OOM,
// so we decrease the concurrency.
const fetchSchemaConcurrency = 1
func (do *Domain) splitForConcurrentFetch(schemas []*model.DBInfo) [][]*model.DBInfo {
groupSize := (len(schemas) + fetchSchemaConcurrency - 1) / fetchSchemaConcurrency
splitted := make([][]*model.DBInfo, 0, fetchSchemaConcurrency)
schemaCnt := len(schemas)
for i := 0; i < schemaCnt; i += groupSize {
end := i + groupSize
if end > schemaCnt {
end = schemaCnt
}
splitted = append(splitted, schemas[i:end])
}
return splitted
}
func (do *Domain) fetchSchemasWithTables(schemas []*model.DBInfo, m *meta.Meta, done chan error) {
for _, di := range schemas {
if di.State != model.StatePublic {
// schema is not public, can't be used outside.
continue
}
tables, err := m.ListTables(di.ID)
if err != nil {
done <- err
return
}
// If TreatOldVersionUTF8AsUTF8MB4 was enable, need to convert the old version schema UTF8 charset to UTF8MB4.
if config.GetGlobalConfig().TreatOldVersionUTF8AsUTF8MB4 {
for _, tbInfo := range tables {
infoschema.ConvertOldVersionUTF8ToUTF8MB4IfNeed(tbInfo)
}
}
di.Tables = make([]*model.TableInfo, 0, len(tables))
for _, tbl := range tables {
if tbl.State != model.StatePublic {
// schema is not public, can't be used outside.
continue
}
infoschema.ConvertCharsetCollateToLowerCaseIfNeed(tbl)
// Check whether the table is in repair mode.
if domainutil.RepairInfo.InRepairMode() && domainutil.RepairInfo.CheckAndFetchRepairedTable(di, tbl) {
continue
}
di.Tables = append(di.Tables, tbl)
}
}
done <- nil
}
// tryLoadSchemaDiffs tries to only load latest schema changes.
// Return true if the schema is loaded successfully.
// Return false if the schema can not be loaded by schema diff, then we need to do full load.
// The second returned value is the delta updated table and partition IDs.
func (do *Domain) tryLoadSchemaDiffs(m *meta.Meta, usedVersion, newVersion int64) (infoschema.InfoSchema, *transaction.RelatedSchemaChange, error) {
var diffs []*model.SchemaDiff
for usedVersion < newVersion {
usedVersion++
diff, err := m.GetSchemaDiff(usedVersion)
if err != nil {
return nil, nil, err
}
if diff == nil {
// Empty diff means the txn of generating schema version is committed, but the txn of `runDDLJob` is not or fail.
// It is safe to skip the empty diff because the infoschema is new enough and consistent.
continue
}
diffs = append(diffs, diff)
}
builder := infoschema.NewBuilder(do.Store(), do.sysFacHack).InitWithOldInfoSchema(do.infoCache.GetLatest())
builder.SetDeltaUpdateBundles()
phyTblIDs := make([]int64, 0, len(diffs))
actions := make([]uint64, 0, len(diffs))
for _, diff := range diffs {
IDs, err := builder.ApplyDiff(m, diff)
if err != nil {
return nil, nil, err
}
if canSkipSchemaCheckerDDL(diff.Type) {
continue
}
phyTblIDs = append(phyTblIDs, IDs...)
for i := 0; i < len(IDs); i++ {
actions = append(actions, uint64(1<<diff.Type))
}
}
is := builder.Build()
relatedChange := transaction.RelatedSchemaChange{}
relatedChange.PhyTblIDS = phyTblIDs
relatedChange.ActionTypes = actions
return is, &relatedChange, nil
}
func canSkipSchemaCheckerDDL(tp model.ActionType) bool {
switch tp {
case model.ActionUpdateTiFlashReplicaStatus, model.ActionSetTiFlashReplica:
return true
}
return false
}
// InfoSchema gets the latest information schema from domain.
func (do *Domain) InfoSchema() infoschema.InfoSchema {
return do.infoCache.GetLatest()
}
// GetSnapshotInfoSchema gets a snapshot information schema.
func (do *Domain) GetSnapshotInfoSchema(snapshotTS uint64) (infoschema.InfoSchema, error) {
// if the snapshotTS is new enough, we can get infoschema directly through sanpshotTS.
if is := do.infoCache.GetBySnapshotTS(snapshotTS); is != nil {
return is, nil
}
is, _, _, _, err := do.loadInfoSchema(snapshotTS)
return is, err
}
// GetSnapshotMeta gets a new snapshot meta at startTS.
func (do *Domain) GetSnapshotMeta(startTS uint64) (*meta.Meta, error) {
snapshot := do.store.GetSnapshot(kv.NewVersion(startTS))
return meta.NewSnapshotMeta(snapshot), nil
}
// ExpiredTimeStamp4PC gets expiredTimeStamp4PC from domain.
func (do *Domain) ExpiredTimeStamp4PC() types.Time {
do.m.Lock()
defer do.m.Unlock()
return do.expiredTimeStamp4PC
}
// SetExpiredTimeStamp4PC sets the expiredTimeStamp4PC from domain.
func (do *Domain) SetExpiredTimeStamp4PC(time types.Time) {
do.m.Lock()
defer do.m.Unlock()
do.expiredTimeStamp4PC = time
}
// DDL gets DDL from domain.
func (do *Domain) DDL() ddl.DDL {
return do.ddl
}
// SetDDL sets DDL to domain, it's only used in tests.
func (do *Domain) SetDDL(d ddl.DDL) {
do.ddl = d
}
// InfoSyncer gets infoSyncer from domain.
func (do *Domain) InfoSyncer() *infosync.InfoSyncer {
return do.info
}
// NotifyGlobalConfigChange notify global config syncer to store the global config into PD.
func (do *Domain) NotifyGlobalConfigChange(name, value string) {
do.globalCfgSyncer.Notify(pd.GlobalConfigItem{Name: name, Value: value})
}
// GetGlobalConfigSyncer exports for testing.
func (do *Domain) GetGlobalConfigSyncer() *globalconfigsync.GlobalConfigSyncer {
return do.globalCfgSyncer
}
// Store gets KV store from domain.
func (do *Domain) Store() kv.Storage {
return do.store
}
// GetScope gets the status variables scope.
func (do *Domain) GetScope(status string) variable.ScopeFlag {
// Now domain status variables scope are all default scope.
return variable.DefaultStatusVarScopeFlag
}
// Reload reloads InfoSchema.
// It's public in order to do the test.
func (do *Domain) Reload() error {
failpoint.Inject("ErrorMockReloadFailed", func(val failpoint.Value) {
if val.(bool) {
failpoint.Return(errors.New("mock reload failed"))
}
})
// Lock here for only once at the same time.
do.m.Lock()
defer do.m.Unlock()
startTime := time.Now()
ver, err := do.store.CurrentVersion(kv.GlobalTxnScope)
if err != nil {
return err
}
is, hitCache, oldSchemaVersion, changes, err := do.loadInfoSchema(ver.Ver)
metrics.LoadSchemaDuration.Observe(time.Since(startTime).Seconds())
if err != nil {
metrics.LoadSchemaCounter.WithLabelValues("failed").Inc()
return err
}
metrics.LoadSchemaCounter.WithLabelValues("succ").Inc()
// only update if it is not from cache
if !hitCache {
// loaded newer schema
if oldSchemaVersion < is.SchemaMetaVersion() {
// Update self schema version to etcd.
err = do.ddl.SchemaSyncer().UpdateSelfVersion(context.Background(), 0, is.SchemaMetaVersion())
if err != nil {
logutil.BgLogger().Info("update self version failed",
zap.Int64("oldSchemaVersion", oldSchemaVersion),
zap.Int64("neededSchemaVersion", is.SchemaMetaVersion()), zap.Error(err))
}
}
// it is full load
if changes == nil {
logutil.BgLogger().Info("full load and reset schema validator")
do.SchemaValidator.Reset()
}
}
// lease renew, so it must be executed despite it is cache or not
do.SchemaValidator.Update(ver.Ver, oldSchemaVersion, is.SchemaMetaVersion(), changes)
lease := do.DDL().GetLease()
sub := time.Since(startTime)
// Reload interval is lease / 2, if load schema time elapses more than this interval,
// some query maybe responded by ErrInfoSchemaExpired error.
if sub > (lease/2) && lease > 0 {
logutil.BgLogger().Warn("loading schema takes a long time", zap.Duration("take time", sub))
}
return nil
}
// LogSlowQuery keeps topN recent slow queries in domain.
func (do *Domain) LogSlowQuery(query *SlowQueryInfo) {
do.slowQuery.mu.RLock()
defer do.slowQuery.mu.RUnlock()
if do.slowQuery.mu.closed {
return
}
select {
case do.slowQuery.ch <- query:
default:
}
}
// ShowSlowQuery returns the slow queries.
func (do *Domain) ShowSlowQuery(showSlow *ast.ShowSlow) []*SlowQueryInfo {
msg := &showSlowMessage{
request: showSlow,
}
msg.Add(1)
do.slowQuery.msgCh <- msg
msg.Wait()
return msg.result
}
func (do *Domain) topNSlowQueryLoop() {
defer util.Recover(metrics.LabelDomain, "topNSlowQueryLoop", nil, false)
ticker := time.NewTicker(time.Minute * 10)
defer func() {
ticker.Stop()
do.wg.Done()
logutil.BgLogger().Info("topNSlowQueryLoop exited.")
}()
for {
select {
case now := <-ticker.C:
do.slowQuery.RemoveExpired(now)
case info, ok := <-do.slowQuery.ch:
if !ok {
return
}
do.slowQuery.Append(info)
case msg := <-do.slowQuery.msgCh:
req := msg.request
switch req.Tp {
case ast.ShowSlowTop:
msg.result = do.slowQuery.QueryTop(int(req.Count), req.Kind)
case ast.ShowSlowRecent:
msg.result = do.slowQuery.QueryRecent(int(req.Count))
default:
msg.result = do.slowQuery.QueryAll()
}
msg.Done()
}
}
}
func (do *Domain) infoSyncerKeeper() {
defer func() {
do.wg.Done()
logutil.BgLogger().Info("infoSyncerKeeper exited.")
util.Recover(metrics.LabelDomain, "infoSyncerKeeper", nil, false)
}()
ticker := time.NewTicker(infosync.ReportInterval)
defer ticker.Stop()
for {
select {
case <-ticker.C:
do.info.ReportMinStartTS(do.Store())
case <-do.info.Done():
logutil.BgLogger().Info("server info syncer need to restart")
if err := do.info.Restart(context.Background()); err != nil {
logutil.BgLogger().Error("server info syncer restart failed", zap.Error(err))
} else {
logutil.BgLogger().Info("server info syncer restarted")
}
case <-do.exit:
return
}
}
}
func (do *Domain) globalConfigSyncerKeeper() {
defer func() {
do.wg.Done()
logutil.BgLogger().Info("globalConfigSyncerKeeper exited.")
util.Recover(metrics.LabelDomain, "globalConfigSyncerKeeper", nil, false)
}()
for {
select {
case entry := <-do.globalCfgSyncer.NotifyCh:
err := do.globalCfgSyncer.StoreGlobalConfig(context.Background(), entry)
if err != nil {
logutil.BgLogger().Error("global config syncer store failed", zap.Error(err))
}
// TODO(crazycs520): Add owner to maintain global config is consistency with global variable.
case <-do.exit:
return
}
}
}
func (do *Domain) topologySyncerKeeper() {
defer util.Recover(metrics.LabelDomain, "topologySyncerKeeper", nil, false)
ticker := time.NewTicker(infosync.TopologyTimeToRefresh)
defer func() {
ticker.Stop()
do.wg.Done()
logutil.BgLogger().Info("topologySyncerKeeper exited.")
}()
for {
select {
case <-ticker.C:
err := do.info.StoreTopologyInfo(context.Background())
if err != nil {
logutil.BgLogger().Error("refresh topology in loop failed", zap.Error(err))
}
case <-do.info.TopologyDone():
logutil.BgLogger().Info("server topology syncer need to restart")
if err := do.info.RestartTopology(context.Background()); err != nil {
logutil.BgLogger().Error("server topology syncer restart failed", zap.Error(err))
} else {
logutil.BgLogger().Info("server topology syncer restarted")
}
case <-do.exit:
return
}
}
}
func (do *Domain) refreshMDLCheckTableInfo() {
se, err := do.sysSessionPool.Get()
if err != nil {
logutil.BgLogger().Warn("get system session failed", zap.Error(err))
return
}
defer do.sysSessionPool.Put(se)
exec := se.(sqlexec.RestrictedSQLExecutor)
domainSchemaVer := do.InfoSchema().SchemaMetaVersion()
rows, _, err := exec.ExecRestrictedSQL(kv.WithInternalSourceType(context.Background(), kv.InternalTxnTelemetry), nil, fmt.Sprintf("select job_id, version, table_ids from mysql.tidb_mdl_info where version <= %d", domainSchemaVer))
if err != nil {
logutil.BgLogger().Warn("get mdl info from tidb_mdl_info failed", zap.Error(err))
return
}
do.mdlCheckTableInfo.mu.Lock()
defer do.mdlCheckTableInfo.mu.Unlock()
do.mdlCheckTableInfo.newestVer = domainSchemaVer
do.mdlCheckTableInfo.jobsVerMap = make(map[int64]int64, len(rows))
do.mdlCheckTableInfo.jobsIdsMap = make(map[int64]string, len(rows))
for i := 0; i < len(rows); i++ {
do.mdlCheckTableInfo.jobsVerMap[rows[i].GetInt64(0)] = rows[i].GetInt64(1)
do.mdlCheckTableInfo.jobsIdsMap[rows[i].GetInt64(0)] = rows[i].GetString(2)
}
}
func (do *Domain) mdlCheckLoop() {
ticker := time.Tick(time.Millisecond * 50)
var saveMaxSchemaVersion int64
jobNeedToSync := false
jobCache := make(map[int64]int64, 1000)
for {
select {
case <-ticker:
if !variable.EnableMDL.Load() {
continue
}
do.mdlCheckTableInfo.mu.Lock()
maxVer := do.mdlCheckTableInfo.newestVer
if maxVer > saveMaxSchemaVersion {
saveMaxSchemaVersion = maxVer
} else if !jobNeedToSync {
// Schema doesn't change, and no job to check in the last run.
do.mdlCheckTableInfo.mu.Unlock()
continue
}
jobNeedToCheckCnt := len(do.mdlCheckTableInfo.jobsVerMap)
if jobNeedToCheckCnt == 0 {
jobNeedToSync = false
do.mdlCheckTableInfo.mu.Unlock()
continue
}
jobsVerMap := make(map[int64]int64, len(do.mdlCheckTableInfo.jobsVerMap))
jobsIdsMap := make(map[int64]string, len(do.mdlCheckTableInfo.jobsIdsMap))
for k, v := range do.mdlCheckTableInfo.jobsVerMap {
jobsVerMap[k] = v
}
for k, v := range do.mdlCheckTableInfo.jobsIdsMap {
jobsIdsMap[k] = v
}
do.mdlCheckTableInfo.mu.Unlock()
jobNeedToSync = true
sm := do.InfoSyncer().GetSessionManager()
if sm == nil {
logutil.BgLogger().Info("session manager is nil")
} else {
sm.CheckOldRunningTxn(jobsVerMap, jobsIdsMap)
}
if len(jobsVerMap) == jobNeedToCheckCnt {
jobNeedToSync = false
}
// Try to gc jobCache.
if len(jobCache) > 1000 {
jobCache = make(map[int64]int64, 1000)
}
for jobID, ver := range jobsVerMap {
if cver, ok := jobCache[jobID]; ok && cver >= ver {
// Already update, skip it.
continue
}
logutil.BgLogger().Info("mdl gets lock, update to owner", zap.Int64("jobID", jobID), zap.Int64("version", ver))
err := do.ddl.SchemaSyncer().UpdateSelfVersion(context.Background(), jobID, ver)
if err != nil {
logutil.BgLogger().Warn("update self version failed", zap.Error(err))
} else {
jobCache[jobID] = ver
}
}
case <-do.exit:
return
}
}
}
func (do *Domain) loadSchemaInLoop(ctx context.Context, lease time.Duration) {
defer util.Recover(metrics.LabelDomain, "loadSchemaInLoop", nil, true)
// Lease renewal can run at any frequency.
// Use lease/2 here as recommend by paper.
ticker := time.NewTicker(lease / 2)
defer func() {
ticker.Stop()
do.wg.Done()
logutil.BgLogger().Info("loadSchemaInLoop exited.")
}()
syncer := do.ddl.SchemaSyncer()
for {
select {
case <-ticker.C:
err := do.Reload()
if err != nil {
logutil.BgLogger().Error("reload schema in loop failed", zap.Error(err))
}
case _, ok := <-syncer.GlobalVersionCh():
err := do.Reload()
if err != nil {
logutil.BgLogger().Error("reload schema in loop failed", zap.Error(err))
}
if !ok {
logutil.BgLogger().Warn("reload schema in loop, schema syncer need rewatch")
// Make sure the rewatch doesn't affect load schema, so we watch the global schema version asynchronously.
syncer.WatchGlobalSchemaVer(context.Background())
}
case <-syncer.Done():
// The schema syncer stops, we need stop the schema validator to synchronize the schema version.
logutil.BgLogger().Info("reload schema in loop, schema syncer need restart")
// The etcd is responsible for schema synchronization, we should ensure there is at most two different schema version
// in the TiDB cluster, to make the data/schema be consistent. If we lost connection/session to etcd, the cluster
// will treats this TiDB as a down instance, and etcd will remove the key of `/tidb/ddl/all_schema_versions/tidb-id`.
// Say the schema version now is 1, the owner is changing the schema version to 2, it will not wait for this down TiDB syncing the schema,
// then continue to change the TiDB schema to version 3. Unfortunately, this down TiDB schema version will still be version 1.
// And version 1 is not consistent to version 3. So we need to stop the schema validator to prohibit the DML executing.
do.SchemaValidator.Stop()
err := do.mustRestartSyncer(ctx)
if err != nil {
logutil.BgLogger().Error("reload schema in loop, schema syncer restart failed", zap.Error(err))
break
}
// The schema maybe changed, must reload schema then the schema validator can restart.
exitLoop := do.mustReload()
// domain is cosed.
if exitLoop {
logutil.BgLogger().Error("domain is closed, exit loadSchemaInLoop")
return
}
do.SchemaValidator.Restart()
logutil.BgLogger().Info("schema syncer restarted")
case <-do.exit:
return
}
do.refreshMDLCheckTableInfo()
}
}
// mustRestartSyncer tries to restart the SchemaSyncer.
// It returns until it's successful or the domain is stoped.
func (do *Domain) mustRestartSyncer(ctx context.Context) error {
syncer := do.ddl.SchemaSyncer()
for {
err := syncer.Restart(ctx)
if err == nil {
return nil
}
// If the domain has stopped, we return an error immediately.
if do.isClose() {
return err
}
logutil.BgLogger().Error("restart the schema syncer failed", zap.Error(err))
time.Sleep(time.Second)
}
}
// mustReload tries to Reload the schema, it returns until it's successful or the domain is closed.
// it returns false when it is successful, returns true when the domain is closed.
func (do *Domain) mustReload() (exitLoop bool) {
for {
err := do.Reload()
if err == nil {
logutil.BgLogger().Info("mustReload succeed")
return false
}
// If the domain is closed, we returns immediately.
logutil.BgLogger().Info("reload the schema failed", zap.Error(err))
if do.isClose() {
return true
}
time.Sleep(200 * time.Millisecond)
}
}
func (do *Domain) isClose() bool {
select {
case <-do.exit:
logutil.BgLogger().Info("domain is closed")
return true
default:
}
return false
}
// Close closes the Domain and release its resource.
func (do *Domain) Close() {
if do == nil {
return
}
startTime := time.Now()
if do.ddl != nil {
terror.Log(do.ddl.Stop())
}
if do.info != nil {
do.info.RemoveServerInfo()
do.info.RemoveMinStartTS()
}
close(do.exit)
if do.etcdClient != nil {
terror.Log(errors.Trace(do.etcdClient.Close()))
}
do.slowQuery.Close()
if do.cancel != nil {
do.cancel()
}
do.wg.Wait()
do.sysSessionPool.Close()
variable.UnregisterStatistics(do.bindHandle)
if do.onClose != nil {
do.onClose()
}
logutil.BgLogger().Info("domain closed", zap.Duration("take time", time.Since(startTime)))
}
const resourceIdleTimeout = 3 * time.Minute // resources in the ResourcePool will be recycled after idleTimeout
// NewDomain creates a new domain. Should not create multiple domains for the same store.
func NewDomain(store kv.Storage, ddlLease time.Duration, statsLease time.Duration, idxUsageSyncLease time.Duration, dumpFileGcLease time.Duration, factory pools.Factory, onClose func()) *Domain {
capacity := 200 // capacity of the sysSessionPool size
do := &Domain{
store: store,
exit: make(chan struct{}),
sysSessionPool: newSessionPool(capacity, factory),
statsLease: statsLease,
infoCache: infoschema.NewCache(16),
slowQuery: newTopNSlowQueries(30, time.Hour*24*7, 500),
indexUsageSyncLease: idxUsageSyncLease,
dumpFileGcChecker: &dumpFileGcChecker{gcLease: dumpFileGcLease, paths: []string{GetPlanReplayerDirName(), GetOptimizerTraceDirName()}},
onClose: onClose,
expiredTimeStamp4PC: types.NewTime(types.ZeroCoreTime, mysql.TypeTimestamp, types.DefaultFsp),
mdlCheckTableInfo: &mdlCheckTableInfo{
mu: sync.Mutex{},
jobsVerMap: make(map[int64]int64),
jobsIdsMap: make(map[int64]string),
},
}
do.SchemaValidator = NewSchemaValidator(ddlLease, do)
do.expensiveQueryHandle = expensivequery.NewExpensiveQueryHandle(do.exit)
do.sysProcesses = SysProcesses{mu: &sync.RWMutex{}, procMap: make(map[uint64]sessionctx.Context)}
variable.SetStatsCacheCapacity.Store(do.SetStatsCacheCapacity)
return do
}
const serverIDForStandalone = 1 // serverID for standalone deployment.
// Init initializes a domain.
func (do *Domain) Init(
ddlLease time.Duration,
sysExecutorFactory func(*Domain) (pools.Resource, error),
ddlInjector func(ddl.DDL) *schematracker.Checker,
) error {
do.sysExecutorFactory = sysExecutorFactory
perfschema.Init()
if ebd, ok := do.store.(kv.EtcdBackend); ok {
var addrs []string
var err error
if addrs, err = ebd.EtcdAddrs(); err != nil {
return err
}
if addrs != nil {
cfg := config.GetGlobalConfig()
// silence etcd warn log, when domain closed, it won't randomly print warn log
// see details at the issue https://github.com/pingcap/tidb/issues/15479
etcdLogCfg := zap.NewProductionConfig()
etcdLogCfg.Level = zap.NewAtomicLevelAt(zap.ErrorLevel)
cli, err := clientv3.New(clientv3.Config{
LogConfig: &etcdLogCfg,
Endpoints: addrs,
AutoSyncInterval: 30 * time.Second,
DialTimeout: 5 * time.Second,
DialOptions: []grpc.DialOption{
grpc.WithBackoffMaxDelay(time.Second * 3),
grpc.WithKeepaliveParams(keepalive.ClientParameters{
Time: time.Duration(cfg.TiKVClient.GrpcKeepAliveTime) * time.Second,
Timeout: time.Duration(cfg.TiKVClient.GrpcKeepAliveTimeout) * time.Second,
}),
},
TLS: ebd.TLSConfig(),
})
if err != nil {
return errors.Trace(err)
}
do.etcdClient = cli
}
}
// TODO: Here we create new sessions with sysFac in DDL,
// which will use `do` as Domain instead of call `domap.Get`.
// That's because `domap.Get` requires a lock, but before
// we initialize Domain finish, we can't require that again.
// After we remove the lazy logic of creating Domain, we
// can simplify code here.
sysFac := func() (pools.Resource, error) {
return sysExecutorFactory(do)
}
sysCtxPool := pools.NewResourcePool(sysFac, 128, 128, resourceIdleTimeout)
ctx, cancelFunc := context.WithCancel(context.Background())
do.cancel = cancelFunc
var callback ddl.Callback
newCallbackFunc, err := ddl.GetCustomizedHook("default_hook")
if err != nil {
return errors.Trace(err)
}
callback = newCallbackFunc(do)
d := do.ddl
do.ddl = ddl.NewDDL(
ctx,
ddl.WithEtcdClient(do.etcdClient),
ddl.WithStore(do.store),
ddl.WithInfoCache(do.infoCache),
ddl.WithHook(callback),
ddl.WithLease(ddlLease),
)
failpoint.Inject("MockReplaceDDL", func(val failpoint.Value) {
if val.(bool) {
do.ddl = d
}
})
if ddlInjector != nil {
checker := ddlInjector(do.ddl)
checker.CreateTestDB()
do.ddl = checker
}
if config.GetGlobalConfig().EnableGlobalKill {
if do.etcdClient != nil {
err := do.acquireServerID(ctx)
if err != nil {
logutil.BgLogger().Error("acquire serverID failed", zap.Error(err))
do.isLostConnectionToPD.Store(1) // will retry in `do.serverIDKeeper`
} else {
do.isLostConnectionToPD.Store(0)
}
do.wg.Add(1)
go do.serverIDKeeper()
} else {
// set serverID for standalone deployment to enable 'KILL'.
atomic.StoreUint64(&do.serverID, serverIDForStandalone)
}
}
// step 1: prepare the info/schema syncer which domain reload needed.
skipRegisterToDashboard := config.GetGlobalConfig().SkipRegisterToDashboard
do.info, err = infosync.GlobalInfoSyncerInit(ctx, do.ddl.GetID(), do.ServerID, do.etcdClient, skipRegisterToDashboard)
if err != nil {
return err
}
var pdClient pd.Client
if store, ok := do.store.(kv.StorageWithPD); ok {
pdClient = store.GetPDClient()
}
do.globalCfgSyncer = globalconfigsync.NewGlobalConfigSyncer(pdClient)
err = do.ddl.SchemaSyncer().Init(ctx)
if err != nil {
return err
}
// step 2: domain reload the infoSchema.
err = do.Reload()
if err != nil {
return err
}
// step 3: start the ddl after the domain reload, avoiding some internal sql running before infoSchema construction.
err = do.ddl.Start(sysCtxPool)
if err != nil {
return err
}
// Only when the store is local that the lease value is 0.
// If the store is local, it doesn't need loadSchemaInLoop.
if ddlLease > 0 {
do.wg.Add(1)
// Local store needs to get the change information for every DDL state in each session.
go do.loadSchemaInLoop(ctx, ddlLease)
}
do.wg.Run(do.mdlCheckLoop)
do.wg.Add(3)
go do.topNSlowQueryLoop()
go do.infoSyncerKeeper()
go do.globalConfigSyncerKeeper()
if !skipRegisterToDashboard {
do.wg.Add(1)
go do.topologySyncerKeeper()
}
if pdClient != nil {
do.wg.Add(1)
go do.closestReplicaReadCheckLoop(ctx, pdClient)
}
err = do.initLogBackup(ctx, pdClient)
if err != nil {
return err
}
return nil
}
func (do *Domain) initLogBackup(ctx context.Context, pdClient pd.Client) error {
cfg := config.GetGlobalConfig()
if pdClient == nil || do.etcdClient == nil {
log.Warn("pd / etcd client not provided, won't begin Advancer.")
return nil
}
env, err := streamhelper.TiDBEnv(pdClient, do.etcdClient, cfg)
if err != nil {
return err
}
adv := streamhelper.NewCheckpointAdvancer(env)
do.logBackupAdvancer = streamhelper.NewAdvancerDaemon(adv, streamhelper.OwnerManagerForLogBackup(ctx, do.etcdClient))
loop, err := do.logBackupAdvancer.Begin(ctx)
if err != nil {
return err
}
do.wg.Run(loop)
return nil
}
// when tidb_replica_read = 'closest-adaptive', check tidb and tikv's zone label matches.
// if not match, disable replica_read to avoid uneven read traffic distribution.
func (do *Domain) closestReplicaReadCheckLoop(ctx context.Context, pdClient pd.Client) {
defer util.Recover(metrics.LabelDomain, "closestReplicaReadCheckLoop", nil, false)
// trigger check once instantly.
if err := do.checkReplicaRead(ctx, pdClient); err != nil {
logutil.BgLogger().Warn("refresh replicaRead flag failed", zap.Error(err))
}
ticker := time.NewTicker(time.Minute)
defer func() {
ticker.Stop()
do.wg.Done()
logutil.BgLogger().Info("closestReplicaReadCheckLoop exited.")
}()
for {
select {
case <-ctx.Done():
return
case <-ticker.C:
if err := do.checkReplicaRead(ctx, pdClient); err != nil {
logutil.BgLogger().Warn("refresh replicaRead flag failed", zap.Error(err))
}
}
}
}
func (do *Domain) checkReplicaRead(ctx context.Context, pdClient pd.Client) error {
// fast path
do.sysVarCache.RLock()
replicaRead := do.sysVarCache.global[variable.TiDBReplicaRead]
do.sysVarCache.RUnlock()
if !strings.EqualFold(replicaRead, "closest-adaptive") {
logutil.BgLogger().Debug("closest replica read is not enabled, skip check!", zap.String("mode", replicaRead))
return nil
}
stores, err := pdClient.GetAllStores(ctx, pd.WithExcludeTombstone())
if err != nil {
return err
}
storeZones := make(map[string]int)
for _, s := range stores {
// skip tumbstone stores or tiflash
if s.NodeState == metapb.NodeState_Removing || s.NodeState == metapb.NodeState_Removed || engine.IsTiFlash(s) {
continue
}
for _, label := range s.Labels {
if label.Key == placement.DCLabelKey && label.Value != "" {
storeZones[label.Value] = 0
break
}
}
}
enabled := false
// if stores don't have zone labels or are distribued in 1 zone, just disable cloeset replica read.
if len(storeZones) > 1 {
enabled = true
servers, err := infosync.GetAllServerInfo(ctx)
if err != nil {
return err
}
for _, s := range servers {
if v, ok := s.Labels[placement.DCLabelKey]; ok && v != "" {
if _, ok := storeZones[v]; !ok {
enabled = false
break
}
storeZones[v] += 1
}
}
if enabled {
for _, count := range storeZones {
if count == 0 {
enabled = false
break
}
}
}
}
if variable.SetEnableAdaptiveReplicaRead(enabled) {
logutil.BgLogger().Info("tidb server adaptive closest replica read is changed", zap.Bool("enable", enabled))
}
return nil
}
type sessionPool struct {
resources chan pools.Resource
factory pools.Factory
mu struct {
sync.RWMutex
closed bool
}
}
func newSessionPool(capacity int, factory pools.Factory) *sessionPool {
return &sessionPool{
resources: make(chan pools.Resource, capacity),
factory: factory,
}
}
func (p *sessionPool) Get() (resource pools.Resource, err error) {
var ok bool
select {
case resource, ok = <-p.resources:
if !ok {
err = errors.New("session pool closed")
}
default:
resource, err = p.factory()
}
// Put the internal session to the map of SessionManager
failpoint.Inject("mockSessionPoolReturnError", func() {
err = errors.New("mockSessionPoolReturnError")
})
if nil == err {
infosync.StoreInternalSession(resource)
}
return
}
func (p *sessionPool) Put(resource pools.Resource) {
p.mu.RLock()
defer p.mu.RUnlock()
// Delete the internal session to the map of SessionManager
infosync.DeleteInternalSession(resource)
if p.mu.closed {
resource.Close()
return
}
select {
case p.resources <- resource:
default:
resource.Close()
}
}
func (p *sessionPool) Close() {
p.mu.Lock()
if p.mu.closed {
p.mu.Unlock()
return
}
p.mu.closed = true
close(p.resources)
p.mu.Unlock()
for r := range p.resources {
r.Close()
}
}
// SysSessionPool returns the system session pool.
func (do *Domain) SysSessionPool() *sessionPool {
return do.sysSessionPool
}
// SysProcTracker returns the system processes tracker.
func (do *Domain) SysProcTracker() sessionctx.SysProcTracker {
return &do.sysProcesses
}
// GetEtcdClient returns the etcd client.
func (do *Domain) GetEtcdClient() *clientv3.Client {
return do.etcdClient
}
// LoadPrivilegeLoop create a goroutine loads privilege tables in a loop, it
// should be called only once in BootstrapSession.
func (do *Domain) LoadPrivilegeLoop(sctx sessionctx.Context) error {
ctx := kv.WithInternalSourceType(context.Background(), kv.InternalTxnPrivilege)
sctx.GetSessionVars().InRestrictedSQL = true
_, err := sctx.(sqlexec.SQLExecutor).ExecuteInternal(ctx, "set @@autocommit = 1")
if err != nil {
return err
}
do.privHandle = privileges.NewHandle()
err = do.privHandle.Update(sctx)
if err != nil {
return err
}
var watchCh clientv3.WatchChan
duration := 5 * time.Minute
if do.etcdClient != nil {
watchCh = do.etcdClient.Watch(context.Background(), privilegeKey)
duration = 10 * time.Minute
}
do.wg.Add(1)
go func() {
defer func() {
do.wg.Done()
logutil.BgLogger().Info("loadPrivilegeInLoop exited.")
util.Recover(metrics.LabelDomain, "loadPrivilegeInLoop", nil, false)
}()
var count int
for {
ok := true
select {
case <-do.exit:
return
case _, ok = <-watchCh:
case <-time.After(duration):
}
if !ok {
logutil.BgLogger().Error("load privilege loop watch channel closed")
watchCh = do.etcdClient.Watch(context.Background(), privilegeKey)
count++
if count > 10 {
time.Sleep(time.Duration(count) * time.Second)
}
continue
}
count = 0
err := do.privHandle.Update(sctx)
metrics.LoadPrivilegeCounter.WithLabelValues(metrics.RetLabel(err)).Inc()
if err != nil {
logutil.BgLogger().Error("load privilege failed", zap.Error(err))
}
}
}()
return nil
}
// LoadSysVarCacheLoop create a goroutine loads sysvar cache in a loop,
// it should be called only once in BootstrapSession.
func (do *Domain) LoadSysVarCacheLoop(ctx sessionctx.Context) error {
ctx.GetSessionVars().InRestrictedSQL = true
err := do.rebuildSysVarCache(ctx)
if err != nil {
return err
}
var watchCh clientv3.WatchChan
duration := 30 * time.Second
if do.etcdClient != nil {
watchCh = do.etcdClient.Watch(context.Background(), sysVarCacheKey)
}
do.wg.Add(1)
go func() {
defer func() {
do.wg.Done()
logutil.BgLogger().Info("LoadSysVarCacheLoop exited.")
util.Recover(metrics.LabelDomain, "LoadSysVarCacheLoop", nil, false)
}()
var count int
for {
ok := true
select {
case <-do.exit:
return
case _, ok = <-watchCh:
case <-time.After(duration):
}
failpoint.Inject("skipLoadSysVarCacheLoop", func(val failpoint.Value) {
// In some pkg integration test, there are many testSuite, and each testSuite has separate storage and
// `LoadSysVarCacheLoop` background goroutine. Then each testSuite `RebuildSysVarCache` from it's
// own storage.
// Each testSuit will also call `checkEnableServerGlobalVar` to update some local variables.
// That's the problem, each testSuit use different storage to update some same local variables.
// So just skip `RebuildSysVarCache` in some integration testing.
if val.(bool) {
failpoint.Continue()
}
})
if !ok {
logutil.BgLogger().Error("LoadSysVarCacheLoop loop watch channel closed")
watchCh = do.etcdClient.Watch(context.Background(), sysVarCacheKey)
count++
if count > 10 {
time.Sleep(time.Duration(count) * time.Second)
}
continue
}
count = 0
logutil.BgLogger().Debug("Rebuilding sysvar cache from etcd watch event.")
err := do.rebuildSysVarCache(ctx)
metrics.LoadSysVarCacheCounter.WithLabelValues(metrics.RetLabel(err)).Inc()
if err != nil {
logutil.BgLogger().Error("LoadSysVarCacheLoop failed", zap.Error(err))
}
}
}()
return nil
}
// PrivilegeHandle returns the MySQLPrivilege.
func (do *Domain) PrivilegeHandle() *privileges.Handle {
return do.privHandle
}
// BindHandle returns domain's bindHandle.
func (do *Domain) BindHandle() *bindinfo.BindHandle {
return do.bindHandle
}
// LoadBindInfoLoop create a goroutine loads BindInfo in a loop, it should
// be called only once in BootstrapSession.
func (do *Domain) LoadBindInfoLoop(ctxForHandle sessionctx.Context, ctxForEvolve sessionctx.Context) error {
ctxForHandle.GetSessionVars().InRestrictedSQL = true
ctxForEvolve.GetSessionVars().InRestrictedSQL = true
do.bindHandle = bindinfo.NewBindHandle(ctxForHandle)
err := do.bindHandle.Update(true)
if err != nil || bindinfo.Lease == 0 {
return err
}
owner := do.newOwnerManager(bindinfo.Prompt, bindinfo.OwnerKey)
do.globalBindHandleWorkerLoop(owner)
do.handleEvolvePlanTasksLoop(ctxForEvolve, owner)
return nil
}
func (do *Domain) globalBindHandleWorkerLoop(owner owner.Manager) {
do.wg.Add(1)
go func() {
defer func() {
do.wg.Done()
logutil.BgLogger().Info("globalBindHandleWorkerLoop exited.")
util.Recover(metrics.LabelDomain, "globalBindHandleWorkerLoop", nil, false)
}()
bindWorkerTicker := time.NewTicker(bindinfo.Lease)
gcBindTicker := time.NewTicker(100 * bindinfo.Lease)
defer func() {
bindWorkerTicker.Stop()
gcBindTicker.Stop()
}()
for {
select {
case <-do.exit:
return
case <-bindWorkerTicker.C:
err := do.bindHandle.Update(false)
if err != nil {
logutil.BgLogger().Error("update bindinfo failed", zap.Error(err))
}
do.bindHandle.DropInvalidBindRecord()
// Get Global
optVal, err := do.GetGlobalVar(variable.TiDBCapturePlanBaseline)
if err == nil && variable.TiDBOptOn(optVal) {
do.bindHandle.CaptureBaselines()
}
do.bindHandle.SaveEvolveTasksToStore()
case <-gcBindTicker.C:
if !owner.IsOwner() {
continue
}
err := do.bindHandle.GCBindRecord()
if err != nil {
logutil.BgLogger().Error("GC bind record failed", zap.Error(err))
}
}
}
}()
}
func (do *Domain) handleEvolvePlanTasksLoop(ctx sessionctx.Context, owner owner.Manager) {
do.wg.Add(1)
go func() {
defer func() {
do.wg.Done()
logutil.BgLogger().Info("handleEvolvePlanTasksLoop exited.")
util.Recover(metrics.LabelDomain, "handleEvolvePlanTasksLoop", nil, false)
}()
for {
select {
case <-do.exit:
owner.Cancel()
return
case <-time.After(bindinfo.Lease):
}
if owner.IsOwner() {
err := do.bindHandle.HandleEvolvePlanTask(ctx, false)
if err != nil {
logutil.BgLogger().Info("evolve plan failed", zap.Error(err))
}
}
}
}()
}
// TelemetryReportLoop create a goroutine that reports usage data in a loop, it should be called only once
// in BootstrapSession.
func (do *Domain) TelemetryReportLoop(ctx sessionctx.Context) {
ctx.GetSessionVars().InRestrictedSQL = true
err := telemetry.InitialRun(ctx, do.GetEtcdClient())
if err != nil {
logutil.BgLogger().Warn("Initial telemetry run failed", zap.Error(err))
}
do.wg.Add(1)
go func() {
defer func() {
do.wg.Done()
logutil.BgLogger().Info("TelemetryReportLoop exited.")
util.Recover(metrics.LabelDomain, "TelemetryReportLoop", nil, false)
}()
owner := do.newOwnerManager(telemetry.Prompt, telemetry.OwnerKey)
for {
select {
case <-do.exit:
owner.Cancel()
return
case <-time.After(telemetry.ReportInterval):
if !owner.IsOwner() {
continue
}
err := telemetry.ReportUsageData(ctx, do.GetEtcdClient())
if err != nil {
// Only status update errors will be printed out
logutil.BgLogger().Warn("TelemetryReportLoop status update failed", zap.Error(err))
}
}
}
}()
}
// TelemetryRotateSubWindowLoop create a goroutine that rotates the telemetry window regularly.
func (do *Domain) TelemetryRotateSubWindowLoop(ctx sessionctx.Context) {
ctx.GetSessionVars().InRestrictedSQL = true
do.wg.Add(1)
go func() {
defer func() {
do.wg.Done()
logutil.BgLogger().Info("TelemetryRotateSubWindowLoop exited.")
util.Recover(metrics.LabelDomain, "TelemetryRotateSubWindowLoop", nil, false)
}()
for {
select {
case <-do.exit:
return
case <-time.After(telemetry.SubWindowSize):
telemetry.RotateSubWindow()
}
}
}()
}
// DumpFileGcCheckerLoop creates a goroutine that handles `exit` and `gc`.
func (do *Domain) DumpFileGcCheckerLoop() {
do.wg.Add(1)
go func() {
gcTicker := time.NewTicker(do.dumpFileGcChecker.gcLease)
defer func() {
gcTicker.Stop()
do.wg.Done()
logutil.BgLogger().Info("dumpFileGcChecker exited.")
util.Recover(metrics.LabelDomain, "dumpFileGcCheckerLoop", nil, false)
}()
for {
select {
case <-do.exit:
return
case <-gcTicker.C:
do.dumpFileGcChecker.gcDumpFiles(time.Hour)
}
}
}()
}
// StatsHandle returns the statistic handle.
func (do *Domain) StatsHandle() *handle.Handle {
return (*handle.Handle)(atomic.LoadPointer(&do.statsHandle))
}
// CreateStatsHandle is used only for test.
func (do *Domain) CreateStatsHandle(ctx sessionctx.Context) error {
h, err := handle.NewHandle(ctx, do.statsLease, do.sysSessionPool, &do.sysProcesses, do.ServerID)
if err != nil {
return err
}
atomic.StorePointer(&do.statsHandle, unsafe.Pointer(h))
return nil
}
// StatsUpdating checks if the stats worker is updating.
func (do *Domain) StatsUpdating() bool {
return do.statsUpdating.Load() > 0
}
// SetStatsUpdating sets the value of stats updating.
func (do *Domain) SetStatsUpdating(val bool) {
if val {
do.statsUpdating.Store(1)
} else {
do.statsUpdating.Store(0)
}
}
// LoadAndUpdateStatsLoop loads and updates stats info.
func (do *Domain) LoadAndUpdateStatsLoop(ctxs []sessionctx.Context) error {
if err := do.UpdateTableStatsLoop(ctxs[0]); err != nil {
return err
}
do.StartLoadStatsSubWorkers(ctxs[1:])
return nil
}
// UpdateTableStatsLoop creates a goroutine loads stats info and updates stats info in a loop.
// It will also start a goroutine to analyze tables automatically.
// It should be called only once in BootstrapSession.
func (do *Domain) UpdateTableStatsLoop(ctx sessionctx.Context) error {
ctx.GetSessionVars().InRestrictedSQL = true
statsHandle, err := handle.NewHandle(ctx, do.statsLease, do.sysSessionPool, &do.sysProcesses, do.ServerID)
if err != nil {
return err
}
atomic.StorePointer(&do.statsHandle, unsafe.Pointer(statsHandle))
do.ddl.RegisterStatsHandle(statsHandle)
// Negative stats lease indicates that it is in test, it does not need update.
if do.statsLease >= 0 {
do.wg.Run(do.loadStatsWorker)
}
owner := do.newOwnerManager(handle.StatsPrompt, handle.StatsOwnerKey)
if do.indexUsageSyncLease > 0 {
do.wg.Add(1)
go do.syncIndexUsageWorker(owner)
}
if do.statsLease <= 0 {
return nil
}
do.SetStatsUpdating(true)
do.wg.Run(func() { do.updateStatsWorker(ctx, owner) })
do.wg.Run(func() { do.autoAnalyzeWorker(owner) })
do.wg.Run(func() { do.gcAnalyzeHistory(owner) })
return nil
}
// StartLoadStatsSubWorkers starts sub workers with new sessions to load stats concurrently.
func (do *Domain) StartLoadStatsSubWorkers(ctxList []sessionctx.Context) {
statsHandle := do.StatsHandle()
for i, ctx := range ctxList {
statsHandle.StatsLoad.SubCtxs[i] = ctx
do.wg.Add(1)
go statsHandle.SubLoadWorker(ctx, do.exit, &do.wg)
}
}
func (do *Domain) newOwnerManager(prompt, ownerKey string) owner.Manager {
id := do.ddl.OwnerManager().ID()
var statsOwner owner.Manager
if do.etcdClient == nil {
statsOwner = owner.NewMockManager(context.Background(), id)
} else {
statsOwner = owner.NewOwnerManager(context.Background(), do.etcdClient, prompt, id, ownerKey)
}
// TODO: Need to do something when err is not nil.
err := statsOwner.CampaignOwner()
if err != nil {
logutil.BgLogger().Warn("campaign owner failed", zap.Error(err))
}
return statsOwner
}
func (do *Domain) loadStatsWorker() {
defer util.Recover(metrics.LabelDomain, "loadStatsWorker", nil, false)
lease := do.statsLease
if lease == 0 {
lease = 3 * time.Second
}
loadTicker := time.NewTicker(lease)
defer func() {
loadTicker.Stop()
logutil.BgLogger().Info("loadStatsWorker exited.")
}()
statsHandle := do.StatsHandle()
t := time.Now()
err := statsHandle.InitStats(do.InfoSchema())
if err != nil {
logutil.BgLogger().Debug("init stats info failed", zap.Error(err))
} else {
logutil.BgLogger().Info("init stats info time", zap.Duration("take time", time.Since(t)))
}
for {
select {
case <-loadTicker.C:
err = statsHandle.RefreshVars()
if err != nil {
logutil.BgLogger().Debug("refresh variables failed", zap.Error(err))
}
err = statsHandle.Update(do.InfoSchema())
if err != nil {
logutil.BgLogger().Debug("update stats info failed", zap.Error(err))
}
err = statsHandle.LoadNeededHistograms()
if err != nil {
logutil.BgLogger().Debug("load histograms failed", zap.Error(err))
}
case <-do.exit:
return
}
}
}
func (do *Domain) syncIndexUsageWorker(owner owner.Manager) {
defer util.Recover(metrics.LabelDomain, "syncIndexUsageWorker", nil, false)
idxUsageSyncTicker := time.NewTicker(do.indexUsageSyncLease)
gcStatsTicker := time.NewTicker(100 * do.indexUsageSyncLease)
handle := do.StatsHandle()
defer func() {
idxUsageSyncTicker.Stop()
do.wg.Done()
logutil.BgLogger().Info("syncIndexUsageWorker exited.")
}()
for {
select {
case <-do.exit:
// TODO: need flush index usage
return
case <-idxUsageSyncTicker.C:
if err := handle.DumpIndexUsageToKV(); err != nil {
logutil.BgLogger().Debug("dump index usage failed", zap.Error(err))
}
case <-gcStatsTicker.C:
if !owner.IsOwner() {
continue
}
if err := handle.GCIndexUsage(); err != nil {
logutil.BgLogger().Error("[stats] gc index usage failed", zap.Error(err))
}
}
}
}
func (do *Domain) updateStatsWorker(ctx sessionctx.Context, owner owner.Manager) {
defer util.Recover(metrics.LabelDomain, "updateStatsWorker", nil, false)
lease := do.statsLease
deltaUpdateTicker := time.NewTicker(20 * lease)
gcStatsTicker := time.NewTicker(100 * lease)
dumpFeedbackTicker := time.NewTicker(200 * lease)
loadFeedbackTicker := time.NewTicker(5 * lease)
dumpColStatsUsageTicker := time.NewTicker(100 * lease)
statsHandle := do.StatsHandle()
defer func() {
dumpColStatsUsageTicker.Stop()
loadFeedbackTicker.Stop()
dumpFeedbackTicker.Stop()
gcStatsTicker.Stop()
deltaUpdateTicker.Stop()
do.SetStatsUpdating(false)
logutil.BgLogger().Info("updateStatsWorker exited.")
}()
for {
select {
case <-do.exit:
statsHandle.FlushStats()
owner.Cancel()
return
// This channel is sent only by ddl owner.
case t := <-statsHandle.DDLEventCh():
err := statsHandle.HandleDDLEvent(t)
if err != nil {
logutil.BgLogger().Debug("handle ddl event failed", zap.Error(err))
}
case <-deltaUpdateTicker.C:
err := statsHandle.DumpStatsDeltaToKV(handle.DumpDelta)
if err != nil {
logutil.BgLogger().Debug("dump stats delta failed", zap.Error(err))
}
statsHandle.UpdateErrorRate(do.InfoSchema())
case <-loadFeedbackTicker.C:
statsHandle.UpdateStatsByLocalFeedback(do.InfoSchema())
if !owner.IsOwner() {
continue
}
err := statsHandle.HandleUpdateStats(do.InfoSchema())
if err != nil {
logutil.BgLogger().Debug("update stats using feedback failed", zap.Error(err))
}
case <-dumpFeedbackTicker.C:
err := statsHandle.DumpStatsFeedbackToKV()
if err != nil {
logutil.BgLogger().Debug("dump stats feedback failed", zap.Error(err))
}
case <-gcStatsTicker.C:
if !owner.IsOwner() {
continue
}
err := statsHandle.GCStats(do.InfoSchema(), do.DDL().GetLease())
if err != nil {
logutil.BgLogger().Debug("GC stats failed", zap.Error(err))
}
case <-dumpColStatsUsageTicker.C:
err := statsHandle.DumpColStatsUsageToKV()
if err != nil {
logutil.BgLogger().Debug("dump column stats usage failed", zap.Error(err))
}
}
}
}
func (do *Domain) autoAnalyzeWorker(owner owner.Manager) {
defer util.Recover(metrics.LabelDomain, "autoAnalyzeWorker", nil, false)
statsHandle := do.StatsHandle()
analyzeTicker := time.NewTicker(do.statsLease)
defer func() {
analyzeTicker.Stop()
logutil.BgLogger().Info("autoAnalyzeWorker exited.")
}()
for {
select {
case <-analyzeTicker.C:
if variable.RunAutoAnalyze.Load() && owner.IsOwner() {
statsHandle.HandleAutoAnalyze(do.InfoSchema())
}
case <-do.exit:
return
}
}
}
func (do *Domain) gcAnalyzeHistory(owner owner.Manager) {
defer util.Recover(metrics.LabelDomain, "gcAnalyzeHistory", nil, false)
const gcInterval = time.Hour
statsHandle := do.StatsHandle()
gcTicker := time.NewTicker(gcInterval)
defer func() {
gcTicker.Stop()
logutil.BgLogger().Info("gcAnalyzeHistory exited.")
}()
for {
select {
case <-gcTicker.C:
if owner.IsOwner() {
const DaysToKeep = 7
updateTime := time.Now().AddDate(0, 0, -DaysToKeep)
err := statsHandle.DeleteAnalyzeJobs(updateTime)
if err != nil {
logutil.BgLogger().Warn("gc analyze history failed", zap.Error(err))
}
}
case <-do.exit:
return
}
}
}
// ExpensiveQueryHandle returns the expensive query handle.
func (do *Domain) ExpensiveQueryHandle() *expensivequery.Handle {
return do.expensiveQueryHandle
}
const (
privilegeKey = "/tidb/privilege"
sysVarCacheKey = "/tidb/sysvars"
)
// NotifyUpdatePrivilege updates privilege key in etcd, TiDB client that watches
// the key will get notification.
func (do *Domain) NotifyUpdatePrivilege() error {
// No matter skip-grant-table is configured or not, sending an etcd message is required.
// Because we need to tell other TiDB instances to update privilege data, say, we're changing the
// password using a special TiDB instance and want the new password to take effect.
if do.etcdClient != nil {
row := do.etcdClient.KV
_, err := row.Put(context.Background(), privilegeKey, "")
if err != nil {
logutil.BgLogger().Warn("notify update privilege failed", zap.Error(err))
}
}
// If skip-grant-table is configured, do not flush privileges.
// Because LoadPrivilegeLoop does not run and the privilege Handle is nil,
// the call to do.PrivilegeHandle().Update would panic.
if config.GetGlobalConfig().Security.SkipGrantTable {
return nil
}
// update locally
sysSessionPool := do.SysSessionPool()
ctx, err := sysSessionPool.Get()
if err != nil {
return err
}
defer sysSessionPool.Put(ctx)
return do.PrivilegeHandle().Update(ctx.(sessionctx.Context))
}
// NotifyUpdateSysVarCache updates the sysvar cache key in etcd, which other TiDB
// clients are subscribed to for updates. For the caller, the cache is also built
// synchronously so that the effect is immediate.
func (do *Domain) NotifyUpdateSysVarCache() {
if do.etcdClient != nil {
row := do.etcdClient.KV
_, err := row.Put(context.Background(), sysVarCacheKey, "")
if err != nil {
logutil.BgLogger().Warn("notify update sysvar cache failed", zap.Error(err))
}
}
// update locally
if err := do.rebuildSysVarCache(nil); err != nil {
logutil.BgLogger().Error("rebuilding sysvar cache failed", zap.Error(err))
}
}
// LoadSigningCertLoop loads the signing cert periodically to make sure it's fresh new.
func (do *Domain) LoadSigningCertLoop() {
do.wg.Add(1)
go func() {
defer func() {
do.wg.Done()
logutil.BgLogger().Debug("loadSigningCertLoop exited.")
util.Recover(metrics.LabelDomain, "LoadSigningCertLoop", nil, false)
}()
for {
select {
case <-time.After(sessionstates.LoadCertInterval):
sessionstates.ReloadSigningCert()
case <-do.exit:
return
}
}
}()
}
// ServerID gets serverID.
func (do *Domain) ServerID() uint64 {
return atomic.LoadUint64(&do.serverID)
}
// IsLostConnectionToPD indicates lost connection to PD or not.
func (do *Domain) IsLostConnectionToPD() bool {
return do.isLostConnectionToPD.Load() != 0
}
const (
serverIDEtcdPath = "/tidb/server_id"
refreshServerIDRetryCnt = 3
acquireServerIDRetryInterval = 300 * time.Millisecond
acquireServerIDTimeout = 10 * time.Second
retrieveServerIDSessionTimeout = 10 * time.Second
)
var (
// serverIDTTL should be LONG ENOUGH to avoid barbarically killing an on-going long-run SQL.
serverIDTTL = 12 * time.Hour
// serverIDTimeToKeepAlive is the interval that we keep serverID TTL alive periodically.
serverIDTimeToKeepAlive = 5 * time.Minute
// serverIDTimeToCheckPDConnectionRestored is the interval that we check connection to PD restored (after broken) periodically.
serverIDTimeToCheckPDConnectionRestored = 10 * time.Second
// lostConnectionToPDTimeout is the duration that when TiDB cannot connect to PD excceeds this limit,
// we realize the connection to PD is lost utterly, and server ID acquired before should be released.
// Must be SHORTER than `serverIDTTL`.
lostConnectionToPDTimeout = 6 * time.Hour
)
var (
ldflagIsGlobalKillTest = "0" // 1:Yes, otherwise:No.
ldflagServerIDTTL = "10" // in seconds.
ldflagServerIDTimeToKeepAlive = "1" // in seconds.
ldflagServerIDTimeToCheckPDConnectionRestored = "1" // in seconds.
ldflagLostConnectionToPDTimeout = "5" // in seconds.
)
func initByLDFlagsForGlobalKill() {
if ldflagIsGlobalKillTest == "1" {
var (
i int
err error
)
if i, err = strconv.Atoi(ldflagServerIDTTL); err != nil {
panic("invalid ldflagServerIDTTL")
}
serverIDTTL = time.Duration(i) * time.Second
if i, err = strconv.Atoi(ldflagServerIDTimeToKeepAlive); err != nil {
panic("invalid ldflagServerIDTimeToKeepAlive")
}
serverIDTimeToKeepAlive = time.Duration(i) * time.Second
if i, err = strconv.Atoi(ldflagServerIDTimeToCheckPDConnectionRestored); err != nil {
panic("invalid ldflagServerIDTimeToCheckPDConnectionRestored")
}
serverIDTimeToCheckPDConnectionRestored = time.Duration(i) * time.Second
if i, err = strconv.Atoi(ldflagLostConnectionToPDTimeout); err != nil {
panic("invalid ldflagLostConnectionToPDTimeout")
}
lostConnectionToPDTimeout = time.Duration(i) * time.Second
logutil.BgLogger().Info("global_kill_test is enabled", zap.Duration("serverIDTTL", serverIDTTL),
zap.Duration("serverIDTimeToKeepAlive", serverIDTimeToKeepAlive),
zap.Duration("serverIDTimeToCheckPDConnectionRestored", serverIDTimeToCheckPDConnectionRestored),
zap.Duration("lostConnectionToPDTimeout", lostConnectionToPDTimeout))
}
}
func (do *Domain) retrieveServerIDSession(ctx context.Context) (*concurrency.Session, error) {
if do.serverIDSession != nil {
return do.serverIDSession, nil
}
// `etcdClient.Grant` needs a shortterm timeout, to avoid blocking if connection to PD lost,
// while `etcdClient.KeepAlive` should be longterm.
// So we separately invoke `etcdClient.Grant` and `concurrency.NewSession` with leaseID.
childCtx, cancel := context.WithTimeout(ctx, retrieveServerIDSessionTimeout)
resp, err := do.etcdClient.Grant(childCtx, int64(serverIDTTL.Seconds()))
cancel()
if err != nil {
logutil.BgLogger().Error("retrieveServerIDSession.Grant fail", zap.Error(err))
return nil, err
}
leaseID := resp.ID
session, err := concurrency.NewSession(do.etcdClient,
concurrency.WithLease(leaseID), concurrency.WithContext(context.Background()))
if err != nil {
logutil.BgLogger().Error("retrieveServerIDSession.NewSession fail", zap.Error(err))
return nil, err
}
do.serverIDSession = session
return session, nil
}
func (do *Domain) acquireServerID(ctx context.Context) error {
atomic.StoreUint64(&do.serverID, 0)
session, err := do.retrieveServerIDSession(ctx)
if err != nil {
return err
}
for {
// get a random serverID: [1, MaxServerID]
randServerID := rand.Int63n(int64(util.MaxServerID)) + 1 // #nosec G404
key := fmt.Sprintf("%s/%v", serverIDEtcdPath, randServerID)
cmp := clientv3.Compare(clientv3.CreateRevision(key), "=", 0)
value := "0"
childCtx, cancel := context.WithTimeout(ctx, acquireServerIDTimeout)
txn := do.etcdClient.Txn(childCtx)
t := txn.If(cmp)
resp, err := t.Then(clientv3.OpPut(key, value, clientv3.WithLease(session.Lease()))).Commit()
cancel()
if err != nil {
return err
}
if !resp.Succeeded {
logutil.BgLogger().Info("proposed random serverID exists, will randomize again", zap.Int64("randServerID", randServerID))
time.Sleep(acquireServerIDRetryInterval)
continue
}
atomic.StoreUint64(&do.serverID, uint64(randServerID))
logutil.BgLogger().Info("acquireServerID", zap.Uint64("serverID", do.ServerID()),
zap.String("lease id", strconv.FormatInt(int64(session.Lease()), 16)))
return nil
}
}
func (do *Domain) refreshServerIDTTL(ctx context.Context) error {
session, err := do.retrieveServerIDSession(ctx)
if err != nil {
return err
}
key := fmt.Sprintf("%s/%v", serverIDEtcdPath, do.ServerID())
value := "0"
err = ddlutil.PutKVToEtcd(ctx, do.etcdClient, refreshServerIDRetryCnt, key, value, clientv3.WithLease(session.Lease()))
if err != nil {
logutil.BgLogger().Error("refreshServerIDTTL fail", zap.Uint64("serverID", do.ServerID()), zap.Error(err))
} else {
logutil.BgLogger().Info("refreshServerIDTTL succeed", zap.Uint64("serverID", do.ServerID()),
zap.String("lease id", strconv.FormatInt(int64(session.Lease()), 16)))
}
return err
}
func (do *Domain) serverIDKeeper() {
defer func() {
do.wg.Done()
logutil.BgLogger().Info("serverIDKeeper exited.")
}()
defer util.Recover(metrics.LabelDomain, "serverIDKeeper", func() {
logutil.BgLogger().Info("recover serverIDKeeper.")
// should be called before `do.wg.Done()`, to ensure that Domain.Close() waits for the new `serverIDKeeper()` routine.
do.wg.Add(1)
go do.serverIDKeeper()
}, false)
tickerKeepAlive := time.NewTicker(serverIDTimeToKeepAlive)
tickerCheckRestored := time.NewTicker(serverIDTimeToCheckPDConnectionRestored)
defer func() {
tickerKeepAlive.Stop()
tickerCheckRestored.Stop()
}()
blocker := make(chan struct{}) // just used for blocking the sessionDone() when session is nil.
sessionDone := func() <-chan struct{} {
if do.serverIDSession == nil {
return blocker
}
return do.serverIDSession.Done()
}
var lastSucceedTimestamp time.Time
onConnectionToPDRestored := func() {
logutil.BgLogger().Info("restored connection to PD")
do.isLostConnectionToPD.Store(0)
lastSucceedTimestamp = time.Now()
if err := do.info.StoreServerInfo(context.Background()); err != nil {
logutil.BgLogger().Error("StoreServerInfo failed", zap.Error(err))
}
}
onConnectionToPDLost := func() {
logutil.BgLogger().Warn("lost connection to PD")
do.isLostConnectionToPD.Store(1)
// Kill all connections when lost connection to PD,
// to avoid the possibility that another TiDB instance acquires the same serverID and generates a same connection ID,
// which will lead to a wrong connection killed.
do.InfoSyncer().GetSessionManager().KillAllConnections()
}
for {
select {
case <-tickerKeepAlive.C:
if !do.IsLostConnectionToPD() {
if err := do.refreshServerIDTTL(context.Background()); err == nil {
lastSucceedTimestamp = time.Now()
} else {
if lostConnectionToPDTimeout > 0 && time.Since(lastSucceedTimestamp) > lostConnectionToPDTimeout {
onConnectionToPDLost()
}
}
}
case <-tickerCheckRestored.C:
if do.IsLostConnectionToPD() {
if err := do.acquireServerID(context.Background()); err == nil {
onConnectionToPDRestored()
}
}
case <-sessionDone():
// inform that TTL of `serverID` is expired. See https://godoc.org/github.com/coreos/etcd/clientv3/concurrency#Session.Done
// Should be in `IsLostConnectionToPD` state, as `lostConnectionToPDTimeout` is shorter than `serverIDTTL`.
// So just set `do.serverIDSession = nil` to restart `serverID` session in `retrieveServerIDSession()`.
logutil.BgLogger().Info("serverIDSession need restart")
do.serverIDSession = nil
case <-do.exit:
return
}
}
}
func init() {
initByLDFlagsForGlobalKill()
telemetry.GetDomainInfoSchema = func(ctx sessionctx.Context) infoschema.InfoSchema {
return GetDomain(ctx).InfoSchema()
}
}
var (
// ErrInfoSchemaExpired returns the error that information schema is out of date.
ErrInfoSchemaExpired = dbterror.ClassDomain.NewStd(errno.ErrInfoSchemaExpired)
// ErrInfoSchemaChanged returns the error that information schema is changed.
ErrInfoSchemaChanged = dbterror.ClassDomain.NewStdErr(errno.ErrInfoSchemaChanged,
mysql.Message(errno.MySQLErrName[errno.ErrInfoSchemaChanged].Raw+". "+kv.TxnRetryableMark, nil))
)
// SysProcesses holds the sys processes infos
type SysProcesses struct {
mu *sync.RWMutex
procMap map[uint64]sessionctx.Context
}
// Track tracks the sys process into procMap
func (s *SysProcesses) Track(id uint64, proc sessionctx.Context) error {
s.mu.Lock()
defer s.mu.Unlock()
if oldProc, ok := s.procMap[id]; ok && oldProc != proc {
return errors.Errorf("The ID is in use: %v", id)
}
s.procMap[id] = proc
proc.GetSessionVars().ConnectionID = id
atomic.StoreUint32(&proc.GetSessionVars().Killed, 0)
return nil
}
// UnTrack removes the sys process from procMap
func (s *SysProcesses) UnTrack(id uint64) {
s.mu.Lock()
defer s.mu.Unlock()
if proc, ok := s.procMap[id]; ok {
delete(s.procMap, id)
proc.GetSessionVars().ConnectionID = 0
atomic.StoreUint32(&proc.GetSessionVars().Killed, 0)
}
}
// GetSysProcessList gets list of system ProcessInfo
func (s *SysProcesses) GetSysProcessList() map[uint64]*util.ProcessInfo {
s.mu.RLock()
defer s.mu.RUnlock()
rs := make(map[uint64]*util.ProcessInfo)
for connID, proc := range s.procMap {
// if session is still tracked in this map, it's not returned to sysSessionPool yet
if pi := proc.ShowProcess(); pi != nil && pi.ID == connID {
rs[connID] = pi
}
}
return rs
}
// KillSysProcess kills sys process with specified ID
func (s *SysProcesses) KillSysProcess(id uint64) {
s.mu.Lock()
defer s.mu.Unlock()
if proc, ok := s.procMap[id]; ok {
atomic.StoreUint32(&proc.GetSessionVars().Killed, 1)
}
}
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