diff --git a/.github/workflows/tests.yml b/.github/workflows/tests.yml
index 2578f71..e5058dc 100644
--- a/.github/workflows/tests.yml
+++ b/.github/workflows/tests.yml
@@ -35,4 +35,4 @@ jobs:
       - name: Unit Test
         run: MOCKEY_DEBUG=true go test -gcflags="all=-l -N" -covermode=atomic -coverprofile=coverage.out ./...
       - name: Benchmark
-        run: go test -bench=. -benchmem -run=none ./...
+        run: go test -gcflags="all=-l -N" -bench=. -benchmem -run=none ./...
diff --git a/internal/monkey/mem/write_darwin.go b/internal/monkey/mem/write_darwin.go
index 8867cec..5c80fae 100644
--- a/internal/monkey/mem/write_darwin.go
+++ b/internal/monkey/mem/write_darwin.go
@@ -28,7 +28,7 @@ import (
 func Write(target uintptr, data []byte) error {
 	targetPage := common.PageOf(target)
 	fnPage := common.PageOf(reflect.ValueOf(write).Pointer())
-	tool.DebugPrintf("Write: target page(0x%x), fn page(0x%x)\n", targetPage, fnPage)
+	tool.DebugPrintf("Write: target page(0x%x), fn page(0x%x), len(%v)\n", targetPage, fnPage, len(data))
 	res := write(target, common.PtrOf(data), len(data), targetPage, common.PageSize(), syscall.PROT_READ|syscall.PROT_EXEC)
 	if res != 0 {
 		return fmt.Errorf("write failed, code %v", res)
diff --git a/internal/monkey/mem/write_linux.go b/internal/monkey/mem/write_linux.go
index 4a85c04..4f60687 100644
--- a/internal/monkey/mem/write_linux.go
+++ b/internal/monkey/mem/write_linux.go
@@ -28,7 +28,7 @@ import (
 func Write(target uintptr, data []byte) error {
 	targetPage := common.PageOf(target)
 	fnPage := common.PageOf(reflect.ValueOf(write).Pointer())
-	tool.DebugPrintf("Write: target page(0x%x), fn page(0x%x)\n", targetPage, fnPage)
+	tool.DebugPrintf("Write: target page(0x%x), fn page(0x%x), len(%v)\n", targetPage, fnPage, len(data))
 	res := write(target, common.PtrOf(data), len(data), targetPage, common.PageSize(), syscall.PROT_READ|syscall.PROT_EXEC)
 	if res != 0 {
 		return fmt.Errorf("write failed, code %v", res)
diff --git a/internal/tool/check_gcflags.go b/internal/tool/check_gcflags.go
new file mode 100644
index 0000000..83a9a8d
--- /dev/null
+++ b/internal/tool/check_gcflags.go
@@ -0,0 +1,36 @@
+/*
+ * Copyright 2022 ByteDance Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package tool
+
+import (
+	"os"
+)
+
+func init() {
+	// set MOCKEY_CHECK_GCFLAGS=false to disable this check
+	checkGCflags()
+}
+
+func checkGCflags() int {
+	if flag := os.Getenv("MOCKEY_CHECK_GCFLAGS"); flag != "false" && !IsGCFlagsSet() {
+		panic(`
+Mockey init failed, did you forget to add -gcflags="all=-N -l" ?
+(Set env MOCKEY_CHECK_GCFLAGS=false to disable gcflags check) 
+		`)
+	}
+	return 0
+}
diff --git a/internal/tool/check_gcflags_amd64.go b/internal/tool/check_gcflags_amd64.go
new file mode 100644
index 0000000..01031c8
--- /dev/null
+++ b/internal/tool/check_gcflags_amd64.go
@@ -0,0 +1,54 @@
+/*
+ * Copyright 2022 ByteDance Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package tool
+
+import (
+	"reflect"
+	"unsafe"
+
+	"golang.org/x/arch/x86/x86asm"
+)
+
+func fn() {
+}
+
+func fn2() {
+	fn()
+}
+
+func IsGCFlagsSet() bool {
+	var asm []byte
+	header := (*reflect.SliceHeader)(unsafe.Pointer(&asm))
+	header.Data = reflect.ValueOf(fn2).Pointer()
+	header.Len = 1000
+	header.Cap = 1000
+
+	flag := false
+	pos := 0
+	for pos < len(asm) {
+		inst, _ := x86asm.Decode(asm[pos:], 64)
+		if inst.Op == x86asm.RET {
+			break
+		}
+		if inst.Op == x86asm.CALL {
+			flag = true
+			break
+		}
+		pos += int(inst.Len)
+	}
+	return flag
+}
diff --git a/internal/tool/check_gcflags_arm64.go b/internal/tool/check_gcflags_arm64.go
new file mode 100644
index 0000000..b38be9b
--- /dev/null
+++ b/internal/tool/check_gcflags_arm64.go
@@ -0,0 +1,54 @@
+/*
+ * Copyright 2022 ByteDance Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package tool
+
+import (
+	"reflect"
+	"unsafe"
+
+	"golang.org/x/arch/arm64/arm64asm"
+)
+
+func fn() {
+}
+
+func fn2() {
+	fn()
+}
+
+func IsGCFlagsSet() bool {
+	var asm []byte
+	header := (*reflect.SliceHeader)(unsafe.Pointer(&asm))
+	header.Data = reflect.ValueOf(fn2).Pointer()
+	header.Len = 1000
+	header.Cap = 1000
+
+	flag := false
+	pos := 0
+	for pos < len(asm) {
+		inst, _ := arm64asm.Decode(asm[pos:])
+		if inst.Op == arm64asm.RET {
+			break
+		}
+		if inst.Op == arm64asm.BL {
+			flag = true
+			break
+		}
+		pos += int(unsafe.Sizeof(inst.Enc))
+	}
+	return flag
+}