diff --git a/core/xray.go b/core/xray.go
index 3e785a823..794ce8fff 100644
--- a/core/xray.go
+++ b/core/xray.go
@@ -4,7 +4,6 @@ import (
 	"context"
 	"reflect"
 	"sync"
-	"sync/atomic"
 
 	"github.com/xtls/xray-core/common"
 	"github.com/xtls/xray-core/common/errors"
@@ -85,7 +84,7 @@ type Instance struct {
 	features                   []features.Feature
 	pendingResolutions         []resolution
 	pendingOptionalResolutions []resolution
-	running                    atomic.Bool
+	running                    bool
 	resolveLock                sync.Mutex
 
 	ctx context.Context
@@ -93,7 +92,9 @@ type Instance struct {
 
 // Instance state
 func (server *Instance) IsRunning() bool {
-	return server.running.Load()
+	server.statusLock.Lock()
+	defer server.statusLock.Unlock()
+	return server.running
 }
 
 func AddInboundHandler(server *Instance, config *InboundHandlerConfig) error {
@@ -263,7 +264,7 @@ func (s *Instance) Close() error {
 	s.statusLock.Lock()
 	defer s.statusLock.Unlock()
 
-	s.running.Store(false)
+	s.running = false
 
 	var errs []interface{}
 	for _, f := range s.features {
@@ -321,7 +322,7 @@ func (s *Instance) RequireFeatures(callback interface{}, optional bool) error {
 
 // AddFeature registers a feature into current Instance.
 func (s *Instance) AddFeature(feature features.Feature) error {
-	if s.running.Load() {
+	if s.IsRunning() {
 		if err := feature.Start(); err != nil {
 			errors.LogInfoInner(s.ctx, err, "failed to start feature")
 		}
@@ -389,7 +390,7 @@ func (s *Instance) Start() error {
 	s.statusLock.Lock()
 	defer s.statusLock.Unlock()
 
-	s.running.Store(true)
+	s.running = true
 	for _, f := range s.features {
 		if err := f.Start(); err != nil {
 			return err
diff --git a/transport/internet/hysteria/config.go b/transport/internet/hysteria/config.go
index 24d4a98be..bf87d604c 100644
--- a/transport/internet/hysteria/config.go
+++ b/transport/internet/hysteria/config.go
@@ -79,7 +79,6 @@ const (
 	StatusNull status = iota
 	StatusActive
 	StatusInactive
-	StatusClosed
 )
 
 const protocolName = "hysteria"
diff --git a/transport/internet/hysteria/dialer.go b/transport/internet/hysteria/dialer.go
index dedc02fd6..29b8a5d18 100644
--- a/transport/internet/hysteria/dialer.go
+++ b/transport/internet/hysteria/dialer.go
@@ -29,6 +29,7 @@ import (
 type client struct {
 	sync.Mutex
 
+	instance     *core.Instance
 	dest         net.Destination
 	config       *Config
 	tlsConfig    *gotls.Config
@@ -36,17 +37,13 @@ type client struct {
 	finalMask    *finalmask.FinalMask
 	quicParams   *internet.QuicParams
 
-	conn     *quic.Conn
-	tr       *quic.Transport
-	pktConn  net.PacketConn
-	udpSM    *udpSessionManager
-	instance *core.Instance
+	conn    *quic.Conn
+	tr      *quic.Transport
+	pktConn net.PacketConn
+	udpSM   *udpSessionManager
 }
 
 func (c *client) status() status {
-	if c.instance != nil && !c.instance.IsRunning() {
-		return StatusClosed
-	}
 	if c.conn == nil {
 		return StatusNull
 	}
@@ -54,16 +51,17 @@ func (c *client) status() status {
 	case <-c.conn.Context().Done():
 		return StatusInactive
 	default:
-		return StatusActive
+		if c.instance == nil || c.instance.IsRunning() {
+			return StatusActive
+		}
+		return StatusInactive
 	}
 }
 
 func (c *client) close() {
-	if c.conn != nil {
-		c.conn.CloseWithError(closeErrCodeOK, "")
-	}
-	common.CloseIfExists(c.tr)
-	common.CloseIfExists(c.pktConn)
+	c.conn.CloseWithError(closeErrCodeOK, "")
+	c.tr.Close()
+	c.pktConn.Close()
 	c.conn = nil
 	c.tr = nil
 	c.pktConn = nil
@@ -71,9 +69,11 @@ func (c *client) close() {
 }
 
 func (c *client) dial(ctx context.Context) error {
-	switch c.status() {
-	case StatusClosed:
+	if c.instance != nil && !c.instance.IsRunning() {
 		return errors.New("client is closed")
+	}
+
+	switch c.status() {
 	case StatusActive:
 		return nil
 	case StatusInactive:
@@ -264,18 +264,13 @@ func (c *client) udp(ctx context.Context) (stat.Connection, error) {
 	return c.udpSM.udp()
 }
 
-func (c *client) clean() (shouldDelete bool) {
+func (c *client) clean() bool {
 	c.Lock()
 	defer c.Unlock()
-	switch c.status() {
-	case StatusClosed:
+	if c.status() == StatusInactive {
 		c.close()
-		return true
-	case StatusInactive:
-		c.close()
-		return false
 	}
-	return false
+	return c.status() == StatusNull
 }
 
 type dialerConf struct {
@@ -291,21 +286,13 @@ type clientManager struct {
 func (m *clientManager) clean() {
 	ticker := time.NewTicker(idleCleanupInterval)
 	for range ticker.C {
-		var toDelete []dialerConf
-		m.RLock()
+		m.Lock()
 		for k, c := range m.m {
 			if c.clean() {
-				toDelete = append(toDelete, k)
-			}
-		}
-		m.RUnlock()
-		if len(toDelete) > 0 {
-			m.Lock()
-			for _, k := range toDelete {
 				delete(m.m, k)
 			}
-			m.Unlock()
 		}
+		m.Unlock()
 	}
 }
 
@@ -331,6 +318,7 @@ func Dial(ctx context.Context, dest net.Destination, streamSettings *internet.Me
 	})
 
 	dialerConfKey := dialerConf{dest, streamSettings}
+
 	manager.RLock()
 	c := manager.m[dialerConfKey]
 	manager.RUnlock()