import psutil
import time

try:
    with open('usage.log', 'a') as log_file:
        while True:
            cpu = psutil.cpu_percent(interval=1)
            memory = psutil.virtual_memory().percent
            log_entry = f"CPU: {cpu}%, Memory: {memory}%\n"
            log_file.write(log_entry)
            log_file.flush()
            time.sleep(4)
except KeyboardInterrupt:
    print('Monitoring stopped by user.')