The problem with refcount of python object

```

1. from functools import lru_cache
2. import fluent.handler
3. import logging
4. import logging.config
5. import sys
6. from concurrent.futures import ThreadPoolExecutor
7.
8. logging.basicConfig(level=logging.INFO)
9.
10. fluentd_format = {
11. 'hostname': '%(hostname)s',
12. 'module': '%(module)s.%(funcName)s',
13. 'where': '%(filename)s:%(lineno)d',
14. 'level': '%(levelname)s',
15. 'exception': '%(exc_text)s',
16. 'process': '%(processName)s',
17. }
18.
19.
20. def fluentd_handler(pendings):
21. if fluentd_handler.first_time:
22. fluentd_handler.first_time = False
23. print("failed to send log to fluentd")
24.
25.
26. fluentd_handler.first_time = True
27.
28. def setup_fluent(tag, host, port):
29. root = logging.getLogger()
30. fluent_handler = fluent.handler.FluentHandler(tag, host=host, port=port,
31. buffer_overflow_handler=fluentd_handler,
32. nanosecond_precision=True)
33. fluent_handler.setLevel(logging.INFO)
34. formatter = fluent.handler.FluentRecordFormatter(fluentd_format)
35. fluent_handler.setFormatter(formatter)
36. root.addHandler(fluent_handler)
37.
38. class TestObj(object):
39. def __init__(self, name, idx):
40. self.name = name
41. self.idx = idx
42.
43. def __del__(self):
44. print("test obj destroyed!")
45.
46. def doing(self):
47. print('name:%s,idx:%s' % (self.name, self.idx))
48.
49.
50. @lru_cache(maxsize=64)
51. def get_object(name , id):
52. return TestObj(name, id);
53.
54.
55. def cache_test():
56. obj1 = get_object('segment000', 0)
57. logging.info("TestObj's refcount is %s", sys.getrefcount(obj1))
58.
59. if __name__ == '__main__':
60. setup_fluent('cachetest', 'localhost', 24224)
61. pool = ThreadPoolExecutor(max_workers=2)
62. for i in range(20):
63. f = pool.submit(cache_test)
64. f.result()
65. logging.info('before clearing,cache info:%s', get_object.cache_info())
66. get_object.cache_clear()
67. logging.info('after clearing,cache info:%s', get_object.cache_info())

```