[전희선] 10주차 미션 제출 (#96)

Author: heehehe

8th_members/전희선/10주차.md

@@ -0,0 +1,44 @@
+### 멀티스레딩 + 스레드 개수 제한 통한 port scanner 실행
+
+- 실행 코드
+    ```python
+    import socket
+    import time
+    from concurrent.futures import ThreadPoolExecutor, as_completed
+    from queue import Queue
+    import sys
+    
+    timeout = 1.0
+    
+    def check_port(host: str, port: int) -> int:
+        with socket.socket(socket.AF_INET, socket.SOCK_STREAM) as sock:
+            sock.settimeout(timeout)
+            result = sock.connect_ex((host, port))
+            if result == 0:
+                return port
+        return None
+    
+    def main():
+        MAX_WORKERS = int(sys.argv[1])  # worker 수 입력으로 받아 다르게 테스트
+    
+        start = time.time()
+        host = "localhost"  # Replace with a host you own
+        open_ports = []
+    
+        with ThreadPoolExecutor(max_workers=MAX_WORKERS) as executor:
+            futures = [executor.submit(check_port, host, port) for port in range(10000, 65536)]  # port 범위 확장 
+    
+            for future in as_completed(futures):
+                port = future.result()
+                if port is not None:
+                    open_ports.append(port)
+    
+        for port in open_ports:
+            print(f"Port {port} is open")
+        print(f"Completed scan in {time.time() - start:.2f} seconds")
+    
+    if __name__ == '__main__':
+        main()
+    ```
+- 결과: worker 수를 30으로 했을 때 가장 적게 걸리는 점을 통해, 멀티스레딩도 오버헤드가 존재하며 (멀티프로세스에 비해 상대적으로 적을 뿐) worker 개수가 많다고 항상 좋은 것은 아니라는 점을 확인할 수 있었습니다 :)
+    <img width="553" alt="image" src="https://github.com/heehehe/CPython-Guide/assets/41580746/ac04e28c-e075-42db-acf8-593efdcc3b3f">