platform: Improve OOM killer for iOS

daemon/started_service.go

@@ -409,7 +409,7 @@ func (s *StartedService) SubscribeStatus(request *SubscribeStatusRequest, server
 
 func (s *StartedService) readStatus() *Status {
 	var status Status
-	status.Memory = memory.Inuse()
+	status.Memory = memory.Total()
 	status.Goroutines = int32(runtime.NumGoroutine())
 	s.serviceAccess.RLock()
 	nowService := s.instance

go.mod

@@ -33,7 +33,7 @@ require (
 	github.com/sagernet/gomobile v0.1.11
 	github.com/sagernet/gvisor v0.0.0-20250811.0-sing-box-mod.1
 	github.com/sagernet/quic-go v0.59.0-sing-box-mod.4
-	github.com/sagernet/sing v0.8.0-beta.16
+	github.com/sagernet/sing v0.8.0-beta.16.0.20260227013657-e419e9875a07
 	github.com/sagernet/sing-mux v0.3.4
 	github.com/sagernet/sing-quic v0.6.0-beta.13
 	github.com/sagernet/sing-shadowsocks v0.2.8

go.sum

@@ -226,8 +226,8 @@ github.com/sagernet/nftables v0.3.0-beta.4 h1:kbULlAwAC3jvdGAC1P5Fa3GSxVwQJibNen
 github.com/sagernet/nftables v0.3.0-beta.4/go.mod h1:OQXAjvjNGGFxaTgVCSTRIhYB5/llyVDeapVoENYBDS8=
 github.com/sagernet/quic-go v0.59.0-sing-box-mod.4 h1:6qvrUW79S+CrPwWz6cMePXohgjHoKxLo3c+MDhNwc3o=
 github.com/sagernet/quic-go v0.59.0-sing-box-mod.4/go.mod h1:OqILvS182CyOol5zNNo6bguvOGgXzV459+chpRaUC+4=
-github.com/sagernet/sing v0.8.0-beta.16 h1:Fe+6E9VHYky9Mx4cf0ugbZPWDcXRflpAu7JQ5bWXvaA=
+github.com/sagernet/sing v0.8.0-beta.16.0.20260227013657-e419e9875a07 h1:LQqb+xtR5uqF6bePmJQ3sAToF/kMCjxSnz17HnboXA8=
-github.com/sagernet/sing v0.8.0-beta.16/go.mod h1:ARkL0gM13/Iv5VCZmci/NuoOlePoIsW0m7BWfln/Hak=
+github.com/sagernet/sing v0.8.0-beta.16.0.20260227013657-e419e9875a07/go.mod h1:ARkL0gM13/Iv5VCZmci/NuoOlePoIsW0m7BWfln/Hak=
 github.com/sagernet/sing-mux v0.3.4 h1:ZQplKl8MNXutjzbMVtWvWG31fohhgOfCuUZR4dVQ8+s=
 github.com/sagernet/sing-mux v0.3.4/go.mod h1:QvlKMyNBNrQoyX4x+gq028uPbLM2XeRpWtDsWBJbFSk=
 github.com/sagernet/sing-quic v0.6.0-beta.13 h1:umDr6GC5fVbOIoTvqV4544wY61zEN+ObQwVGNP8sX1M=

option/oom_killer.go

@@ -1,3 +1,14 @@
 package option
 
-type OOMKillerServiceOptions struct{}
+import (
+	"github.com/sagernet/sing/common/byteformats"
+	"github.com/sagernet/sing/common/json/badoption"
+)
+
+type OOMKillerServiceOptions struct {
+	MemoryLimit       *byteformats.MemoryBytes `json:"memory_limit,omitempty"`
+	SafetyMargin      *byteformats.MemoryBytes `json:"safety_margin,omitempty"`
+	MinInterval       badoption.Duration       `json:"min_interval,omitempty"`
+	MaxInterval       badoption.Duration       `json:"max_interval,omitempty"`
+	ChecksBeforeLimit int                      `json:"checks_before_limit,omitempty"`
+}

service/oomkiller/config.go

@@ -0,0 +1,51 @@
+package oomkiller
+
+import (
+	"time"
+
+	"github.com/sagernet/sing-box/option"
+	E "github.com/sagernet/sing/common/exceptions"
+)
+
+func buildTimerConfig(options option.OOMKillerServiceOptions, memoryLimit uint64, useAvailable bool) (timerConfig, error) {
+	safetyMargin := uint64(defaultSafetyMargin)
+	if options.SafetyMargin != nil && options.SafetyMargin.Value() > 0 {
+		safetyMargin = options.SafetyMargin.Value()
+	}
+
+	minInterval := defaultMinInterval
+	if options.MinInterval != 0 {
+		minInterval = time.Duration(options.MinInterval.Build())
+		if minInterval <= 0 {
+			return timerConfig{}, E.New("min_interval must be greater than 0")
+		}
+	}
+
+	maxInterval := defaultMaxInterval
+	if options.MaxInterval != 0 {
+		maxInterval = time.Duration(options.MaxInterval.Build())
+		if maxInterval <= 0 {
+			return timerConfig{}, E.New("max_interval must be greater than 0")
+		}
+	}
+	if maxInterval < minInterval {
+		return timerConfig{}, E.New("max_interval must be greater than or equal to min_interval")
+	}
+
+	checksBeforeLimit := defaultChecksBeforeLimit
+	if options.ChecksBeforeLimit != 0 {
+		checksBeforeLimit = options.ChecksBeforeLimit
+		if checksBeforeLimit <= 0 {
+			return timerConfig{}, E.New("checks_before_limit must be greater than 0")
+		}
+	}
+
+	return timerConfig{
+		memoryLimit:       memoryLimit,
+		safetyMargin:      safetyMargin,
+		minInterval:       minInterval,
+		maxInterval:       maxInterval,
+		checksBeforeLimit: checksBeforeLimit,
+		useAvailable:      useAvailable,
+	}, nil
+}

service/oomkiller/service.go

@@ -59,35 +59,70 @@ type Service struct {
 	boxService.Adapter
 	logger        log.ContextLogger
 	router        adapter.Router
+	memoryLimit   uint64
+	hasTimerMode  bool
+	useAvailable  bool
+	timerConfig   timerConfig
+	adaptiveTimer *adaptiveTimer
 }
 
 func NewService(ctx context.Context, logger log.ContextLogger, tag string, options option.OOMKillerServiceOptions) (adapter.Service, error) {
-	return &Service{
+	s := &Service{
 		Adapter: boxService.NewAdapter(boxConstant.TypeOOMKiller, tag),
 		logger:  logger,
 		router:  service.FromContext[adapter.Router](ctx),
-	}, nil
+	}
+
+	if options.MemoryLimit != nil {
+		s.memoryLimit = options.MemoryLimit.Value()
+		if s.memoryLimit > 0 {
+			s.hasTimerMode = true
+		}
+	}
+
+	config, err := buildTimerConfig(options, s.memoryLimit, s.useAvailable)
+	if err != nil {
+		return nil, err
+	}
+	s.timerConfig = config
+
+	return s, nil
 }
 
 func (s *Service) Start(stage adapter.StartStage) error {
 	if stage != adapter.StartStateStart {
 		return nil
 	}
+
+	if s.hasTimerMode {
+		s.adaptiveTimer = newAdaptiveTimer(s.logger, s.router, s.timerConfig)
+		if s.memoryLimit > 0 {
+			s.logger.Info("started memory monitor with limit: ", s.memoryLimit/(1024*1024), " MiB")
+		} else {
+			s.logger.Info("started memory monitor with available memory detection")
+		}
+	} else {
+		s.logger.Info("started memory pressure monitor")
+	}
+
 	globalAccess.Lock()
 	isFirst := len(globalServices) == 0
 	globalServices = append(globalServices, s)
 	globalAccess.Unlock()
+
 	if isFirst {
 		C.startMemoryPressureMonitor()
 	}
-	s.logger.Info("started memory pressure monitor")
 	return nil
 }
 
 func (s *Service) Close() error {
+	if s.adaptiveTimer != nil {
+		s.adaptiveTimer.stop()
+	}
 	globalAccess.Lock()
-	for i, service := range globalServices {
+	for i, svc := range globalServices {
-		if service == s {
+		if svc == s {
 			globalServices = append(globalServices[:i], globalServices[i+1:]...)
 			break
 		}
@@ -122,17 +157,36 @@ func goMemoryPressureCallback(status C.ulong) {
 	default:
 		level = "normal"
 	}
+	var freeOSMemory bool
 	for _, s := range services {
+		usage := memory.Total()
+		if s.hasTimerMode {
 			if isCritical {
-			s.logger.Error("memory pressure: ", level, ", usage: ", memory.Total()/(1024*1024), " MiB, resetting network")
+				s.logger.Warn("memory pressure: ", level, ", usage: ", usage/(1024*1024), " MiB")
-			s.router.ResetNetwork()
+				if s.adaptiveTimer != nil {
+					s.adaptiveTimer.startNow()
+				}
 			} else if isWarning {
-			s.logger.Warn("memory pressure: ", level, ", usage: ", memory.Total()/(1024*1024), " MiB")
+				s.logger.Warn("memory pressure: ", level, ", usage: ", usage/(1024*1024), " MiB")
 			} else {
-			s.logger.Debug("memory pressure: ", level, ", usage: ", memory.Total()/(1024*1024), " MiB")
+				s.logger.Debug("memory pressure: ", level, ", usage: ", usage/(1024*1024), " MiB")
+				if s.adaptiveTimer != nil {
+					s.adaptiveTimer.stop()
 				}
 			}
+		} else {
 			if isCritical {
+				s.logger.Error("memory pressure: ", level, ", usage: ", usage/(1024*1024), " MiB, resetting network")
+				s.router.ResetNetwork()
+				freeOSMemory = true
+			} else if isWarning {
+				s.logger.Warn("memory pressure: ", level, ", usage: ", usage/(1024*1024), " MiB")
+			} else {
+				s.logger.Debug("memory pressure: ", level, ", usage: ", usage/(1024*1024), " MiB")
+			}
+		}
+	}
+	if freeOSMemory {
 		runtimeDebug.FreeOSMemory()
 	}
 }

service/oomkiller/service_stub.go

@@ -7,33 +7,75 @@ import (
 
 	"github.com/sagernet/sing-box/adapter"
 	boxService "github.com/sagernet/sing-box/adapter/service"
-	C "github.com/sagernet/sing-box/constant"
+	boxConstant "github.com/sagernet/sing-box/constant"
 	"github.com/sagernet/sing-box/log"
 	"github.com/sagernet/sing-box/option"
 	E "github.com/sagernet/sing/common/exceptions"
+	"github.com/sagernet/sing/common/memory"
+	"github.com/sagernet/sing/service"
 )
 
 func RegisterService(registry *boxService.Registry) {
-	boxService.Register[option.OOMKillerServiceOptions](registry, C.TypeOOMKiller, NewService)
+	boxService.Register[option.OOMKillerServiceOptions](registry, boxConstant.TypeOOMKiller, NewService)
 }
 
 type Service struct {
 	boxService.Adapter
+	logger        log.ContextLogger
+	router        adapter.Router
+	adaptiveTimer *adaptiveTimer
+	timerConfig   timerConfig
+	hasTimerMode  bool
+	useAvailable  bool
+	memoryLimit   uint64
 }
 
 func NewService(ctx context.Context, logger log.ContextLogger, tag string, options option.OOMKillerServiceOptions) (adapter.Service, error) {
-	return &Service{
+	s := &Service{
-		Adapter: boxService.NewAdapter(C.TypeOOMKiller, tag),
+		Adapter: boxService.NewAdapter(boxConstant.TypeOOMKiller, tag),
-	}, nil
+		logger:  logger,
+		router:  service.FromContext[adapter.Router](ctx),
+	}
+
+	if options.MemoryLimit != nil {
+		s.memoryLimit = options.MemoryLimit.Value()
+	}
+	if s.memoryLimit > 0 {
+		s.hasTimerMode = true
+	} else if memory.AvailableSupported() {
+		s.useAvailable = true
+		s.hasTimerMode = true
+	}
+
+	config, err := buildTimerConfig(options, s.memoryLimit, s.useAvailable)
+	if err != nil {
+		return nil, err
+	}
+	s.timerConfig = config
+
+	return s, nil
 }
 
 func (s *Service) Start(stage adapter.StartStage) error {
 	if stage != adapter.StartStateStart {
 		return nil
 	}
-	return E.New("memory pressure monitoring is not available on this platform")
+	if !s.hasTimerMode {
+		return E.New("memory pressure monitoring is not available on this platform without memory_limit")
+	}
+	s.adaptiveTimer = newAdaptiveTimer(s.logger, s.router, s.timerConfig)
+	s.adaptiveTimer.start(0)
+	if s.useAvailable {
+		s.logger.Info("started memory monitor with available memory detection")
+	} else {
+		s.logger.Info("started memory monitor with limit: ", s.memoryLimit/(1024*1024), " MiB")
+	}
+	return nil
 }
 
 func (s *Service) Close() error {
+	if s.adaptiveTimer != nil {
+		s.adaptiveTimer.stop()
+	}
 	return nil
 }

service/oomkiller/service_timer.go

@@ -0,0 +1,158 @@
+package oomkiller
+
+import (
+	runtimeDebug "runtime/debug"
+	"sync"
+	"time"
+
+	"github.com/sagernet/sing-box/adapter"
+	"github.com/sagernet/sing-box/log"
+	"github.com/sagernet/sing/common/memory"
+)
+
+const (
+	defaultChecksBeforeLimit = 4
+	defaultMinInterval       = 500 * time.Millisecond
+	defaultMaxInterval       = 10 * time.Second
+	defaultSafetyMargin      = 5 * 1024 * 1024
+)
+
+type adaptiveTimer struct {
+	logger            log.ContextLogger
+	router            adapter.Router
+	memoryLimit       uint64
+	safetyMargin      uint64
+	minInterval       time.Duration
+	maxInterval       time.Duration
+	checksBeforeLimit int
+	useAvailable      bool
+
+	access        sync.Mutex
+	timer         *time.Timer
+	previousUsage uint64
+	lastInterval  time.Duration
+}
+
+type timerConfig struct {
+	memoryLimit       uint64
+	safetyMargin      uint64
+	minInterval       time.Duration
+	maxInterval       time.Duration
+	checksBeforeLimit int
+	useAvailable      bool
+}
+
+func newAdaptiveTimer(logger log.ContextLogger, router adapter.Router, config timerConfig) *adaptiveTimer {
+	return &adaptiveTimer{
+		logger:            logger,
+		router:            router,
+		memoryLimit:       config.memoryLimit,
+		safetyMargin:      config.safetyMargin,
+		minInterval:       config.minInterval,
+		maxInterval:       config.maxInterval,
+		checksBeforeLimit: config.checksBeforeLimit,
+		useAvailable:      config.useAvailable,
+	}
+}
+
+func (t *adaptiveTimer) start(_ uint64) {
+	t.access.Lock()
+	defer t.access.Unlock()
+	t.startLocked()
+}
+
+func (t *adaptiveTimer) startNow() {
+	t.access.Lock()
+	t.startLocked()
+	t.access.Unlock()
+	t.poll()
+}
+
+func (t *adaptiveTimer) startLocked() {
+	if t.timer != nil {
+		return
+	}
+	t.previousUsage = memory.Total()
+	t.lastInterval = t.minInterval
+	t.timer = time.AfterFunc(t.minInterval, t.poll)
+}
+
+func (t *adaptiveTimer) stop() {
+	t.access.Lock()
+	defer t.access.Unlock()
+	t.stopLocked()
+}
+
+func (t *adaptiveTimer) stopLocked() {
+	if t.timer != nil {
+		t.timer.Stop()
+		t.timer = nil
+	}
+}
+
+func (t *adaptiveTimer) running() bool {
+	t.access.Lock()
+	defer t.access.Unlock()
+	return t.timer != nil
+}
+
+func (t *adaptiveTimer) poll() {
+	t.access.Lock()
+	defer t.access.Unlock()
+	if t.timer == nil {
+		return
+	}
+
+	usage := memory.Total()
+	delta := int64(usage) - int64(t.previousUsage)
+	t.previousUsage = usage
+
+	var remaining uint64
+	var triggered bool
+
+	if t.memoryLimit > 0 {
+		if usage >= t.memoryLimit {
+			remaining = 0
+			triggered = true
+		} else {
+			remaining = t.memoryLimit - usage
+		}
+	} else if t.useAvailable {
+		available := memory.Available()
+		if available <= t.safetyMargin {
+			remaining = 0
+			triggered = true
+		} else {
+			remaining = available - t.safetyMargin
+		}
+	} else {
+		remaining = 0
+	}
+
+	if triggered {
+		t.logger.Error("memory threshold reached, usage: ", usage/(1024*1024), " MiB, resetting network")
+		t.router.ResetNetwork()
+		runtimeDebug.FreeOSMemory()
+	}
+
+	var interval time.Duration
+	if triggered {
+		interval = t.maxInterval
+	} else if delta <= 0 {
+		interval = t.maxInterval
+	} else if t.checksBeforeLimit <= 0 {
+		interval = t.maxInterval
+	} else {
+		timeToLimit := time.Duration(float64(remaining) / float64(delta) * float64(t.lastInterval))
+		interval = timeToLimit / time.Duration(t.checksBeforeLimit)
+		if interval < t.minInterval {
+			interval = t.minInterval
+		}
+		if interval > t.maxInterval {
+			interval = t.maxInterval
+		}
+	}
+
+	t.lastInterval = interval
+	t.timer.Reset(interval)
+}