ddl: reduce the time to run unit tests (pingcap#8585)

ddl/db_partition_test.go

@@ -1019,8 +1019,6 @@ func (s *testIntegrationSuite) TestPartitionCancelAddIndex(c *C) {
 	var checkErr error
 	var c3IdxInfo *model.IndexInfo
 	hook := &ddl.TestDDLCallback{}
-	oldReorgWaitTimeout := ddl.ReorgWaitTimeout
-	ddl.ReorgWaitTimeout = 10 * time.Millisecond
 	hook.OnJobUpdatedExported, c3IdxInfo, checkErr = backgroundExecOnJobUpdatedExported(c, s.store, s.ctx, hook)
 	s.dom.DDL().(ddl.DDLForTest).SetHook(hook)
 	done := make(chan error, 1)
@@ -1065,15 +1063,13 @@ LOOP:
 	checkDelRangeDone(c, s.ctx, idx)
 
 	tk.MustExec("drop table t1")
-	ddl.ReorgWaitTimeout = oldReorgWaitTimeout
 	callback := &ddl.TestDDLCallback{}
 	s.dom.DDL().(ddl.DDLForTest).SetHook(callback)
 }
 
 func backgroundExecOnJobUpdatedExported(c *C, store kv.Storage, ctx sessionctx.Context, hook *ddl.TestDDLCallback) (func(*model.Job), *model.IndexInfo, error) {
 	var checkErr error
 	first := true
-	ddl.ReorgWaitTimeout = 10 * time.Millisecond
 	c3IdxInfo := &model.IndexInfo{}
 	hook.OnJobUpdatedExported = func(job *model.Job) {
 		addIndexNotFirstReorg := job.Type == model.ActionAddIndex && job.SchemaState == model.StateWriteReorganization && job.SnapshotVer != 0

ddl/ddl_test.go

@@ -27,6 +27,7 @@ import (
 	"github.com/pingcap/tidb/infoschema"
 	"github.com/pingcap/tidb/kv"
 	"github.com/pingcap/tidb/meta"
+	"github.com/pingcap/tidb/meta/autoid"
 	"github.com/pingcap/tidb/sessionctx"
 	"github.com/pingcap/tidb/store/mockstore"
 	"github.com/pingcap/tidb/types"
@@ -100,6 +101,8 @@ func TestT(t *testing.T) {
 		Level:  logLevel,
 		Format: "highlight",
 	})
+	autoid.SetStep(5000)
+	ReorgWaitTimeout = 30 * time.Millisecond
 	TestingT(t)
 }
 

ddl/ddl_worker_test.go

@@ -42,9 +42,10 @@ const testLease = 5 * time.Millisecond
 
 func (s *testDDLSuite) SetUpSuite(c *C) {
 	testleak.BeforeTest()
-	// set ReorgWaitTimeout to small value, make test to be faster.
-	ReorgWaitTimeout = 50 * time.Millisecond
 	WaitTimeWhenErrorOccured = 1 * time.Microsecond
+
+	// We hope that this test is serially executed. So put it here.
+	s.testRunWorker(c)
 }
 
 func (s *testDDLSuite) TearDownSuite(c *C) {
@@ -63,8 +64,8 @@ func (s *testDDLSuite) TestCheckOwner(c *C) {
 	c.Assert(d1.GetLease(), Equals, testLease)
 }
 
-// TestRunWorker tests no job is handled when the value of RunWorker is false.
-func (s *testDDLSuite) TestRunWorker(c *C) {
+// testRunWorker tests no job is handled when the value of RunWorker is false.
+func (s *testDDLSuite) testRunWorker(c *C) {
 	store := testCreateStore(c, "test_run_worker")
 	defer store.Close()
 
@@ -784,7 +785,6 @@ func (s *testDDLSuite) TestDDLPackageExecuteSQL(c *C) {
 	store := testCreateStore(c, "test_run_sql")
 	defer store.Close()
 
-	RunWorker = true
 	d := testNewDDL(context.Background(), nil, store, nil, nil, testLease)
 	testCheckOwner(c, d, true)
 	defer d.Stop()

ddl/failtest/fail_db_test.go

@@ -229,6 +229,11 @@ func (s *testFailDBSuite) TestFailSchemaSyncer(c *C) {
 	tk.MustExec("drop table if exists t")
 	tk.MustExec("create table t(a int)")
 	defer tk.MustExec("drop table if exists t")
+	originalRetryTimes := domain.SchemaOutOfDateRetryTimes
+	domain.SchemaOutOfDateRetryTimes = 1
+	defer func() {
+		domain.SchemaOutOfDateRetryTimes = originalRetryTimes
+	}()
 	c.Assert(s.dom.SchemaValidator.IsStarted(), IsTrue)
 	mockSyncer, ok := s.dom.DDL().SchemaSyncer().(*ddl.MockSchemaSyncer)
 	c.Assert(ok, IsTrue)

sessionctx/variable/statusvar.go

@@ -16,11 +16,13 @@ package variable
 import (
 	"bytes"
 	"crypto/tls"
+	"sync"
 
 	"github.com/pingcap/errors"
 )
 
 var statisticsList []Statistics
+var statisticsListLock sync.RWMutex
 
 // DefaultStatusVarScopeFlag is the default scope of status variables.
 var DefaultStatusVarScopeFlag = ScopeGlobal | ScopeSession
@@ -41,13 +43,17 @@ type Statistics interface {
 
 // RegisterStatistics registers statistics.
 func RegisterStatistics(s Statistics) {
+	statisticsListLock.Lock()
 	statisticsList = append(statisticsList, s)
+	statisticsListLock.Unlock()
 }
 
 // GetStatusVars gets registered statistics status variables.
 // TODO: Refactor this function to avoid repeated memory allocation / dealloc
 func GetStatusVars(vars *SessionVars) (map[string]*StatusVal, error) {
 	statusVars := make(map[string]*StatusVal)
+	statisticsListLock.RLock()
+	defer statisticsListLock.RUnlock()
 
 	for _, statistics := range statisticsList {
 		vals, err := statistics.Stats(vars)