session,parser: make MAX_EXECUTION_TIME sql hint and global variable …

…work (#10999)
pingcap · Jul 1, 2019 · db151cc · db151cc
1 parent 8d757ee
commit db151cc
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Showing 5 changed files with 24 additions and 5 deletions.
diff --git a/domain/global_vars_cache.go b/domain/global_vars_cache.go
@@ -27,6 +27,9 @@ type GlobalVariableCache struct {
 	lastModify time.Time
 	rows       []chunk.Row
 	fields     []*ast.ResultField
+
+	// Unit test may like to disable it.
+	disable bool
 }
 
 const globalVariableCacheExpiry time.Duration = 2 * time.Second
@@ -44,14 +47,22 @@ func (gvc *GlobalVariableCache) Update(rows []chunk.Row, fields []*ast.ResultFie
 func (gvc *GlobalVariableCache) Get() (succ bool, rows []chunk.Row, fields []*ast.ResultField) {
 	gvc.RLock()
 	defer gvc.RUnlock()
-	if time.Now().Sub(gvc.lastModify) < globalVariableCacheExpiry {
-		succ, rows, fields = true, gvc.rows, gvc.fields
+	if time.Since(gvc.lastModify) < globalVariableCacheExpiry {
+		succ, rows, fields = !gvc.disable, gvc.rows, gvc.fields
 		return
 	}
 	succ = false
 	return
 }
 
+// Disable disables the global variabe cache, used in test only.
+func (gvc *GlobalVariableCache) Disable() {
+	gvc.Lock()
+	defer gvc.Unlock()
+	gvc.disable = true
+	return
+}
+
 // GetGlobalVarsCache gets the global variable cache.
 func (do *Domain) GetGlobalVarsCache() *GlobalVariableCache {
 	return &do.gvc

diff --git a/go.mod b/go.mod
@@ -49,7 +49,7 @@ require (
 	github.com/pingcap/goleveldb v0.0.0-20171020084629-8d44bfdf1030
 	github.com/pingcap/kvproto v0.0.0-20190429124202-32a5ba2af0f7
 	github.com/pingcap/log v0.0.0-20190307075452-bd41d9273596
-	github.com/pingcap/parser v0.0.0-20190620042621-a13211687e55
+	github.com/pingcap/parser v0.0.0-20190701060323-a2aa507d6352
 	github.com/pingcap/pd v2.1.12+incompatible
 	github.com/pingcap/tidb-tools v2.1.3-0.20190116051332-34c808eef588+incompatible
 	github.com/pingcap/tipb v0.0.0-20180910045846-371b48b15d93

diff --git a/go.sum b/go.sum
@@ -103,8 +103,8 @@ github.com/pingcap/kvproto v0.0.0-20190429124202-32a5ba2af0f7 h1:+wEqJTc74Jvoxen
 github.com/pingcap/kvproto v0.0.0-20190429124202-32a5ba2af0f7/go.mod h1:0gwbe1F2iBIjuQ9AH0DbQhL+Dpr5GofU8fgYyXk+ykk=
 github.com/pingcap/log v0.0.0-20190307075452-bd41d9273596 h1:t2OQTpPJnrPDGlvA+3FwJptMTt6MEPdzK1Wt99oaefQ=
 github.com/pingcap/log v0.0.0-20190307075452-bd41d9273596/go.mod h1:WpHUKhNZ18v116SvGrmjkA9CBhYmuUTKL+p8JC9ANEw=
-github.com/pingcap/parser v0.0.0-20190620042621-a13211687e55 h1:JSr9saxYwDyIte70taWbKX83fCUww80HjrcyDnFokBg=
-github.com/pingcap/parser v0.0.0-20190620042621-a13211687e55/go.mod h1:1FNvfp9+J0wvc4kl8eGNh7Rqrxveg15jJoWo/a0uHwA=
+github.com/pingcap/parser v0.0.0-20190701060323-a2aa507d6352 h1:bqNncrTvLJyxLx8rHr5tDe4wYhfVFoegj+LrOoFwwuM=
+github.com/pingcap/parser v0.0.0-20190701060323-a2aa507d6352/go.mod h1:1FNvfp9+J0wvc4kl8eGNh7Rqrxveg15jJoWo/a0uHwA=
 github.com/pingcap/pd v2.1.12+incompatible h1:6N3LBxx2aSZqT+IWEG730EDNDttP7dXO8J6yvBh+HXw=
 github.com/pingcap/pd v2.1.12+incompatible/go.mod h1:nD3+EoYes4+aNNODO99ES59V83MZSI+dFbhyr667a0E=
 github.com/pingcap/tidb-tools v2.1.3-0.20190116051332-34c808eef588+incompatible h1:e9Gi/LP9181HT3gBfSOeSBA+5JfemuE4aEAhqNgoE4k=

diff --git a/session/session.go b/session/session.go
@@ -1411,6 +1411,7 @@ var builtinGlobalVariable = []string{
 	variable.MaxAllowedPacket,
 	variable.TimeZone,
 	variable.BlockEncryptionMode,
+	variable.MaxExecutionTime,
 	/* TiDB specific global variables: */
 	variable.TiDBSkipUTF8Check,
 	variable.TiDBIndexJoinBatchSize,

diff --git a/session/session_test.go b/session/session_test.go
@@ -406,6 +406,13 @@ func (s *testSessionSuite) TestGlobalVarAccessor(c *C) {
 	c.Assert(err, IsNil)
 	c.Assert(v, Equals, varValue2)
 
+	// For issue 10955, make sure the new session load `max_execution_time` into sessionVars.
+	s.dom.GetGlobalVarsCache().Disable()
+	tk1.MustExec("set @@global.max_execution_time = 100")
+	tk2 := testkit.NewTestKitWithInit(c, s.store)
+	c.Assert(tk2.Se.GetSessionVars().MaxExecutionTime, Equals, uint64(100))
+	tk1.MustExec("set @@global.max_execution_time = 0")
+
 	result := tk.MustQuery("show global variables  where variable_name='sql_select_limit';")
 	result.Check(testkit.Rows("sql_select_limit 18446744073709551615"))
 	result = tk.MustQuery("show session variables  where variable_name='sql_select_limit';")