2006, 'MySQL server has gone away' 2013, 'Lost connection to MySQL server during query

[kiven-man]

Describe the bug I have some scheduled tasks, get the connection operation database through the connection pool, and perform the task operation database again to report MySQL 2006 and MySQL2013 error.

my setting: DATABASES = { 'default': { 'ENGINE': 'dj_db_conn_pool.backends.mysql', 'NAME': SQL_DB, 'USER': SQL_USER, 'HOST': SQL_HOST, 'POOL_OPTIONS': { 'POOL_SIZE': 5, 'MAX_OVERFLOW': -1, 'RECYCLE': 60 } }, }

Environment

• Python Version: 3.7
• Django Version: 2.2.4

Traceback The above exception was the direct cause of the following exception:

Traceback (most recent call last): File "", line 1, in File "/Users/admin/Desktop/code/virtualenv/mbot/lib/python3.9/site-packages/django/db/models/query.py", line 263, in repr data = list(self[:REPR_OUTPUT_SIZE + 1]) File "/Users/admin/Desktop/code/virtualenv/mbot/lib/python3.9/site-packages/django/db/models/query.py", line 269, in len self._fetch_all() File "/Users/admin/Desktop/code/virtualenv/mbot/lib/python3.9/site-packages/django/db/models/query.py", line 1308, in _fetch_all self._result_cache = list(self._iterable_class(self)) File "/Users/admin/Desktop/code/virtualenv/mbot/lib/python3.9/site-packages/django/db/models/query.py", line 53, in iter results = compiler.execute_sql(chunked_fetch=self.chunked_fetch, chunk_size=self.chunk_size) File "/Users/admin/Desktop/code/virtualenv/mbot/lib/python3.9/site-packages/django/db/models/sql/compiler.py", line 1156, in execute_sql cursor.execute(sql, params) File "/Users/admin/Desktop/code/virtualenv/mbot/lib/python3.9/site-packages/django/db/backends/utils.py", line 98, in execute return super().execute(sql, params) File "/Users/admin/Desktop/code/virtualenv/mbot/lib/python3.9/site-packages/django/db/backends/utils.py", line 66, in execute return self._execute_with_wrappers(sql, params, many=False, executor=self._execute) File "/Users/admin/Desktop/code/virtualenv/mbot/lib/python3.9/site-packages/django/db/backends/utils.py", line 75, in _execute_with_wrappers return executor(sql, params, many, context) File "/Users/admin/Desktop/code/virtualenv/mbot/lib/python3.9/site-packages/django/db/backends/utils.py", line 84, in _execute return self.cursor.execute(sql, params) File "/Users/admin/Desktop/code/virtualenv/mbot/lib/python3.9/site-packages/django/db/utils.py", line 90, in exit raise dj_exc_value.with_traceback(traceback) from exc_value File "/Users/admin/Desktop/code/virtualenv/mbot/lib/python3.9/site-packages/django/db/backends/utils.py", line 84, in _execute return self.cursor.execute(sql, params) File "/Users/admin/Desktop/code/virtualenv/mbot/lib/python3.9/site-packages/django/db/backends/mysql/base.py", line 73, in execute return self.cursor.execute(query, args) File "/Users/admin/Desktop/code/virtualenv/mbot/lib/python3.9/site-packages/MySQLdb/cursors.py", line 206, in execute res = self._query(query) File "/Users/admin/Desktop/code/virtualenv/mbot/lib/python3.9/site-packages/MySQLdb/cursors.py", line 319, in _query db.query(q) File "/Users/admin/Desktop/code/virtualenv/mbot/lib/python3.9/site-packages/MySQLdb/connections.py", line 259, in query _mysql.connection.query(self, query) django.db.utils.OperationalError: (2006, 'MySQL server has gone away')

Traceback (most recent call last): File "", line 1, in File "/Users/admin/Desktop/code/virtualenv/mbot/lib/python3.9/site-packages/django/db/models/query.py", line 263, in repr data = list(self[:REPR_OUTPUT_SIZE + 1]) File "/Users/admin/Desktop/code/virtualenv/mbot/lib/python3.9/site-packages/django/db/models/query.py", line 269, in len self._fetch_all() File "/Users/admin/Desktop/code/virtualenv/mbot/lib/python3.9/site-packages/django/db/models/query.py", line 1308, in _fetch_all self._result_cache = list(self._iterable_class(self)) File "/Users/admin/Desktop/code/virtualenv/mbot/lib/python3.9/site-packages/django/db/models/query.py", line 53, in iter results = compiler.execute_sql(chunked_fetch=self.chunked_fetch, chunk_size=self.chunk_size) File "/Users/admin/Desktop/code/virtualenv/mbot/lib/python3.9/site-packages/django/db/models/sql/compiler.py", line 1156, in execute_sql cursor.execute(sql, params) File "/Users/admin/Desktop/code/virtualenv/mbot/lib/python3.9/site-packages/django/db/backends/utils.py", line 98, in execute return super().execute(sql, params) File "/Users/admin/Desktop/code/virtualenv/mbot/lib/python3.9/site-packages/django/db/backends/utils.py", line 66, in execute return self._execute_with_wrappers(sql, params, many=False, executor=self._execute) File "/Users/admin/Desktop/code/virtualenv/mbot/lib/python3.9/site-packages/django/db/backends/utils.py", line 75, in _execute_with_wrappers return executor(sql, params, many, context) File "/Users/admin/Desktop/code/virtualenv/mbot/lib/python3.9/site-packages/django/db/backends/utils.py", line 84, in _execute return self.cursor.execute(sql, params) File "/Users/admin/Desktop/code/virtualenv/mbot/lib/python3.9/site-packages/django/db/utils.py", line 90, in exit raise dj_exc_value.with_traceback(traceback) from exc_value File "/Users/admin/Desktop/code/virtualenv/mbot/lib/python3.9/site-packages/django/db/backends/utils.py", line 84, in _execute return self.cursor.execute(sql, params) File "/Users/admin/Desktop/code/virtualenv/mbot/lib/python3.9/site-packages/django/db/backends/mysql/base.py", line 73, in execute return self.cursor.execute(query, args) File "/Users/admin/Desktop/code/virtualenv/mbot/lib/python3.9/site-packages/MySQLdb/cursors.py", line 206, in execute res = self._query(query) File "/Users/admin/Desktop/code/virtualenv/mbot/lib/python3.9/site-packages/MySQLdb/cursors.py", line 319, in _query db.query(q) File "/Users/admin/Desktop/code/virtualenv/mbot/lib/python3.9/site-packages/MySQLdb/connections.py", line 259, in query _mysql.connection.query(self, query) django.db.utils.OperationalError: (2013, 'Lost connection to MySQL server during query')

[altairbow]

Due to network error?

[kiven-man]

Due to network error?

No, I don't know how connection pooling keeps connections active and how to allocate valid connections. I'm guessing there's a problem with the connection pool allocation that caused the problem above.

[altairbow]

Use django's built-in backend to see if this problem continues