config: disable prepare plan cache by default

pingcap · Mar 9, 2021 · 42d7a14 · 42d7a14
1 parent f6a61bc
commit 42d7a14
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Showing 4 changed files with 16 additions and 6 deletions.
diff --git a/config/config.go b/config/config.go
@@ -617,7 +617,7 @@ var defaultConf = Config{
 		HeaderTimeout: 5,
 	},
 	PreparedPlanCache: PreparedPlanCache{
-		Enabled:          true,
+		Enabled:          false,
 		Capacity:         100,
 		MemoryGuardRatio: 0.1,
 	},

diff --git a/config/config.toml.example b/config/config.toml.example
@@ -312,7 +312,7 @@ networks = ""
 header-timeout = 5
 
 [prepared-plan-cache]
-enabled = true
+enabled = false
 capacity = 100
 memory-guard-ratio = 0.1
 

diff --git a/expression/integration_test.go b/expression/integration_test.go
@@ -5893,9 +5893,19 @@ func (s *testIntegrationSuite) TestCastStrToInt(c *C) {
 func (s *testIntegrationSerialSuite) TestPreparePlanCache(c *C) {
 	tk := testkit.NewTestKit(c, s.store)
 
-	// Plan cache should now be on by default
-	c.Assert(plannercore.PreparedPlanCacheEnabled(), Equals, true)
+	// Plan cache should now be off by default
+	c.Assert(plannercore.PreparedPlanCacheEnabled(), Equals, false)
 
+	orgEnable := plannercore.PreparedPlanCacheEnabled()
+	defer func() {
+		plannercore.SetPreparedPlanCache(orgEnable)
+	}()
+	plannercore.SetPreparedPlanCache(true)
+	var err error
+	tk.Se, err = session.CreateSession4TestWithOpt(s.store, &session.Opt{
+		PreparedPlanCache: kvcache.NewSimpleLRUCache(100, 0.1, math.MaxUint64),
+	})
+	c.Assert(err, IsNil)
 	// Use the example from the docs https://docs.pingcap.com/tidb/stable/sql-prepare-plan-cache
 	tk.MustExec("use test")
 	tk.MustExec("drop table if exists t;")

diff --git a/planner/core/cache.go b/planner/core/cache.go
@@ -32,8 +32,8 @@ import (
 
 var (
 	// preparedPlanCacheEnabledValue stores the global config "prepared-plan-cache-enabled".
-	// The value is true unless "prepared-plan-cache-enabled" is FALSE in configuration.
-	preparedPlanCacheEnabledValue int32 = 1
+	// The value is false unless "prepared-plan-cache-enabled" is true in configuration.
+	preparedPlanCacheEnabledValue int32 = 0
 	// PreparedPlanCacheCapacity stores the global config "prepared-plan-cache-capacity".
 	PreparedPlanCacheCapacity uint = 100
 	// PreparedPlanCacheMemoryGuardRatio stores the global config "prepared-plan-cache-memory-guard-ratio".