diff --git a/config/config.go b/config/config.go
index db1b883..104bed3 100644
--- a/config/config.go
+++ b/config/config.go
@@ -19,9 +19,9 @@ type ConfYaml struct {
 // SectionCore is sub seciont of config.
 type SectionCore struct {
 	Port            string     `yaml:"port"`
-	MaxNotification int        `yaml:"max_notification"`
-	WorkerNum       int        `yaml:"worker_num"`
-	QueueNum        int        `yaml:"queue_num"`
+	MaxNotification int64      `yaml:"max_notification"`
+	WorkerNum       int64      `yaml:"worker_num"`
+	QueueNum        int64      `yaml:"queue_num"`
 	Mode            string     `yaml:"mode"`
 	SSL             bool       `yaml:"ssl"`
 	CertPath        string     `yaml:"cert_path"`
@@ -102,13 +102,13 @@ func BuildDefaultPushConf() ConfYaml {
 
 	// Core
 	conf.Core.Port = "8088"
-	conf.Core.WorkerNum = runtime.NumCPU()
-	conf.Core.QueueNum = 8192
+	conf.Core.WorkerNum = int64(runtime.NumCPU())
+	conf.Core.QueueNum = int64(8192)
 	conf.Core.Mode = "release"
 	conf.Core.SSL = false
 	conf.Core.CertPath = "cert.pem"
 	conf.Core.KeyPath = "key.pem"
-	conf.Core.MaxNotification = 100
+	conf.Core.MaxNotification = int64(100)
 	conf.Core.HTTPProxy = ""
 	conf.Core.PID.Enabled = false
 	conf.Core.PID.Path = "gorush.pid"
diff --git a/config/config_test.go b/config/config_test.go
index fb59ddb..c22e674 100644
--- a/config/config_test.go
+++ b/config/config_test.go
@@ -55,13 +55,13 @@ func (suite *ConfigTestSuite) SetupTest() {
 func (suite *ConfigTestSuite) TestValidateConfDefault() {
 	// Core
 	assert.Equal(suite.T(), "8088", suite.ConfGorushDefault.Core.Port)
-	assert.Equal(suite.T(), runtime.NumCPU(), suite.ConfGorushDefault.Core.WorkerNum)
-	assert.Equal(suite.T(), 8192, suite.ConfGorushDefault.Core.QueueNum)
+	assert.Equal(suite.T(), int64(runtime.NumCPU()), suite.ConfGorushDefault.Core.WorkerNum)
+	assert.Equal(suite.T(), int64(8192), suite.ConfGorushDefault.Core.QueueNum)
 	assert.Equal(suite.T(), "release", suite.ConfGorushDefault.Core.Mode)
 	assert.Equal(suite.T(), false, suite.ConfGorushDefault.Core.SSL)
 	assert.Equal(suite.T(), "cert.pem", suite.ConfGorushDefault.Core.CertPath)
 	assert.Equal(suite.T(), "key.pem", suite.ConfGorushDefault.Core.KeyPath)
-	assert.Equal(suite.T(), 100, suite.ConfGorushDefault.Core.MaxNotification)
+	assert.Equal(suite.T(), int64(100), suite.ConfGorushDefault.Core.MaxNotification)
 	assert.Equal(suite.T(), "", suite.ConfGorushDefault.Core.HTTPProxy)
 	// Pid
 	assert.Equal(suite.T(), false, suite.ConfGorushDefault.Core.PID.Enabled)
@@ -107,13 +107,13 @@ func (suite *ConfigTestSuite) TestValidateConfDefault() {
 func (suite *ConfigTestSuite) TestValidateConf() {
 	// Core
 	assert.Equal(suite.T(), "8088", suite.ConfGorush.Core.Port)
-	assert.Equal(suite.T(), 8, suite.ConfGorush.Core.WorkerNum)
-	assert.Equal(suite.T(), 8192, suite.ConfGorush.Core.QueueNum)
+	assert.Equal(suite.T(), int64(8), suite.ConfGorush.Core.WorkerNum)
+	assert.Equal(suite.T(), int64(8192), suite.ConfGorush.Core.QueueNum)
 	assert.Equal(suite.T(), "release", suite.ConfGorush.Core.Mode)
 	assert.Equal(suite.T(), false, suite.ConfGorush.Core.SSL)
 	assert.Equal(suite.T(), "cert.pem", suite.ConfGorush.Core.CertPath)
 	assert.Equal(suite.T(), "key.pem", suite.ConfGorush.Core.KeyPath)
-	assert.Equal(suite.T(), 100, suite.ConfGorush.Core.MaxNotification)
+	assert.Equal(suite.T(), int64(100), suite.ConfGorush.Core.MaxNotification)
 	assert.Equal(suite.T(), "", suite.ConfGorush.Core.HTTPProxy)
 	// Pid
 	assert.Equal(suite.T(), false, suite.ConfGorush.Core.PID.Enabled)
diff --git a/gorush.go b/gorush.go
index 841c22b..f7c8d7b 100644
--- a/gorush.go
+++ b/gorush.go
@@ -236,6 +236,6 @@ func main() {
 
 	gorush.InitAppStatus()
 	gorush.InitAPNSClient()
-	gorush.InitWorkers(gorush.PushConf.Core.WorkerNum, gorush.PushConf.Core.QueueNum)
+	gorush.InitWorkers(int64(gorush.PushConf.Core.WorkerNum), int64(gorush.PushConf.Core.QueueNum))
 	gorush.RunHTTPServer()
 }
diff --git a/gorush/notification.go b/gorush/notification.go
index 078a1d9..d7d75f2 100644
--- a/gorush/notification.go
+++ b/gorush/notification.go
@@ -186,10 +186,10 @@ func InitAPNSClient() error {
 }
 
 // InitWorkers for initialize all workers.
-func InitWorkers(workerNum, queueNum int) {
+func InitWorkers(workerNum int64, queueNum int64) {
 	LogAccess.Debug("worker number is ", workerNum, ", queue number is ", queueNum)
 	QueueNotification = make(chan PushNotification, queueNum)
-	for i := 0; i < workerNum; i++ {
+	for i := int64(0); i < workerNum; i++ {
 		go startWorker()
 	}
 }
diff --git a/gorush/notification_test.go b/gorush/notification_test.go
index 71f23e8..5f8f1de 100644
--- a/gorush/notification_test.go
+++ b/gorush/notification_test.go
@@ -329,7 +329,7 @@ func TestOverwriteAndroidAPIKey(t *testing.T) {
 func TestSenMultipleNotifications(t *testing.T) {
 	PushConf = config.BuildDefaultPushConf()
 
-	InitWorkers(2, 2)
+	InitWorkers(int64(2), 2)
 
 	PushConf.Ios.Enabled = true
 	PushConf.Ios.KeyPath = "../certificate/certificate-valid.pem"
diff --git a/gorush/server.go b/gorush/server.go
index 0f7318e..892a404 100644
--- a/gorush/server.go
+++ b/gorush/server.go
@@ -40,7 +40,7 @@ func pushHandler(c *gin.Context) {
 		return
 	}
 
-	if len(form.Notifications) > PushConf.Core.MaxNotification {
+	if int64(len(form.Notifications)) > PushConf.Core.MaxNotification {
 		msg = fmt.Sprintf("Number of notifications(%d) over limit(%d)", len(form.Notifications), PushConf.Core.MaxNotification)
 		LogAccess.Debug(msg)
 		abortWithError(c, http.StatusBadRequest, msg)
diff --git a/gorush/server_test.go b/gorush/server_test.go
index 2555e1b..7e88f67 100644
--- a/gorush/server_test.go
+++ b/gorush/server_test.go
@@ -151,7 +151,7 @@ func TestEmptyNotifications(t *testing.T) {
 func TestOutOfRangeMaxNotifications(t *testing.T) {
 	initTest()
 
-	PushConf.Core.MaxNotification = 1
+	PushConf.Core.MaxNotification = int64(1)
 
 	r := gofight.New()