config: Revise SimpleLRUCache Configuration

config/config.go

@@ -363,8 +363,10 @@ type Status struct {
 
 // Performance is the performance section of the config.
 type Performance struct {
-	MaxProcs             uint    `toml:"max-procs" json:"max-procs"`
+	MaxProcs uint `toml:"max-procs" json:"max-procs"`
+	// Deprecated: use ServerMemoryQuota instead
 	MaxMemory            uint64  `toml:"max-memory" json:"max-memory"`
+	ServerMemoryQuota    uint64  `toml:"server-memory-quota" json:"server-memory-quota"`
 	StatsLease           string  `toml:"stats-lease" json:"stats-lease"`
 	StmtCountLimit       uint    `toml:"stmt-count-limit" json:"stmt-count-limit"`
 	FeedbackProbability  float64 `toml:"feedback-probability" json:"feedback-probability"`
@@ -603,6 +605,7 @@ var defaultConf = Config{
 	},
 	Performance: Performance{
 		MaxMemory:            0,
+		ServerMemoryQuota:    0,
 		TCPKeepAlive:         true,
 		CrossJoin:            true,
 		StatsLease:           "3s",
@@ -714,6 +717,7 @@ var deprecatedConfig = map[string]struct{}{
 	"txn-local-latches":          {},
 	"txn-local-latches.enabled":  {},
 	"txn-local-latches.capacity": {},
+	"performance.max-memory":     {},
 	"max-txn-time-use":           {},
 }
 

config/config.toml.example

@@ -200,8 +200,8 @@ record-db-qps = false
 # Max CPUs to use, 0 use number of CPUs in the machine.
 max-procs = 0
 
-# Max memory size to use, 0 use the total usable memory in the machine.
-max-memory = 0
+# Memory size quota for tidb server, 0 means unlimited
+server-memory-quota = 0
 
 # StmtCountLimit limits the max count of statement inside a transaction.
 stmt-count-limit = 5000

planner/core/cache.go

@@ -39,7 +39,7 @@ var (
 	PreparedPlanCacheCapacity uint = 100
 	// PreparedPlanCacheMemoryGuardRatio stores the global config "prepared-plan-cache-memory-guard-ratio".
 	PreparedPlanCacheMemoryGuardRatio = 0.1
-	// PreparedPlanCacheMaxMemory stores the max memory size defined in the global config "performance-max-memory".
+	// PreparedPlanCacheMaxMemory stores the max memory size defined in the global config "performance-server-memory-quota".
 	PreparedPlanCacheMaxMemory = *atomic2.NewUint64(math.MaxUint64)
 )
 

tidb-server/main.go

@@ -408,8 +408,8 @@ func reloadConfig(nc, c *config.Config) {
 	// like config.GetGlobalConfig().OOMAction.
 	// These config items will become available naturally after the global config pointer
 	// is updated in function ReloadGlobalConfig.
-	if nc.Performance.MaxMemory != c.Performance.MaxMemory {
-		plannercore.PreparedPlanCacheMaxMemory.Store(nc.Performance.MaxMemory)
+	if nc.Performance.ServerMemoryQuota != c.Performance.ServerMemoryQuota {
+		plannercore.PreparedPlanCacheMaxMemory.Store(nc.Performance.ServerMemoryQuota)
 	}
 	if nc.Performance.CrossJoin != c.Performance.CrossJoin {
 		plannercore.AllowCartesianProduct.Store(nc.Performance.CrossJoin)
@@ -598,7 +598,7 @@ func setGlobalVars() {
 		if plannercore.PreparedPlanCacheMemoryGuardRatio < 0.0 || plannercore.PreparedPlanCacheMemoryGuardRatio > 1.0 {
 			plannercore.PreparedPlanCacheMemoryGuardRatio = 0.1
 		}
-		plannercore.PreparedPlanCacheMaxMemory.Store(cfg.Performance.MaxMemory)
+		plannercore.PreparedPlanCacheMaxMemory.Store(cfg.Performance.ServerMemoryQuota)
 		total, err := memory.MemTotal()
 		terror.MustNil(err)
 		if plannercore.PreparedPlanCacheMaxMemory.Load() > total || plannercore.PreparedPlanCacheMaxMemory.Load() <= 0 {
@@ -612,11 +612,11 @@ func setGlobalVars() {
 	domainutil.RepairInfo.SetRepairTableList(cfg.RepairTableList)
 	c := config.GetGlobalConfig()
 	executor.GlobalDiskUsageTracker.SetBytesLimit(c.TempStorageQuota)
-	if c.Performance.MaxMemory < 1 {
+	if c.Performance.ServerMemoryQuota < 1 {
 		// If MaxMemory equals 0, it means unlimited
 		executor.GlobalMemoryUsageTracker.SetBytesLimit(-1)
 	} else {
-		executor.GlobalMemoryUsageTracker.SetBytesLimit(int64(c.Performance.MaxMemory))
+		executor.GlobalMemoryUsageTracker.SetBytesLimit(int64(c.Performance.ServerMemoryQuota))
 	}
 	kvcache.GlobalLRUMemUsageTracker.AttachToGlobalTracker(executor.GlobalMemoryUsageTracker)
 }