Sometimes I get this error and server stops:

ERROR: could not serialize access due to concurrent update

2021-08-30 16:20:24,394 27 INFO paxchi_dbc odoo.service.model: SERIALIZATION_FAILURE, retry 2/5 in 0.9523 sec...

2021-08-30 16:20:26,245 27 INFO paxchi_dbc odoo.service.server: Dumping stacktrace of limit exceeding threads before reloading

2021-08-30 16:20:26,327 27 INFO paxchi_dbc odoo.tools.misc:

# Thread: (db:paxchi_dbc) (uid:9) (url:http://crm.paxchi.com/longpolling/poll)

File: "/opt/bitnami/python/lib/python3.6/threading.py", line 884, in _bootstrap

  self._bootstrap_inner()

File: "/opt/bitnami/python/lib/python3.6/threading.py", line 916, in _bootstrap_inner

  self.run()

File: "/opt/bitnami/python/lib/python3.6/threading.py", line 864, in run

  self._target(*self._args, **self._kwargs)

File: "/opt/bitnami/python/lib/python3.6/socketserver.py", line 654, in process_request_thread

  self.finish_request(request, client_address)

File: "/opt/bitnami/python/lib/python3.6/socketserver.py", line 364, in finish_request

  self.RequestHandlerClass(request, client_address, self)

File: "/opt/bitnami/python/lib/python3.6/socketserver.py", line 724, in __init__

  self.handle()

File: "/opt/bitnami/odoo/venv/lib/python3.6/site-packages/werkzeug/serving.py", line 293, in handle

  rv = BaseHTTPRequestHandler.handle(self)

File: "/opt/bitnami/python/lib/python3.6/http/server.py", line 418, in handle

  self.handle_one_request()

File: "/opt/bitnami/odoo/venv/lib/python3.6/site-packages/werkzeug/serving.py", line 328, in handle_one_request

  return self.run_wsgi()

File: "/opt/bitnami/odoo/venv/lib/python3.6/site-packages/werkzeug/serving.py", line 270, in run_wsgi

  execute(self.server.app)

File: "/opt/bitnami/odoo/venv/lib/python3.6/site-packages/werkzeug/serving.py", line 258, in execute

  application_iter = app(environ, start_response)

File: "/opt/bitnami/odoo/odoo/service/server.py", line 439, in app

  return self.app(e, s)

File: "/opt/bitnami/odoo/odoo/service/wsgi_server.py", line 142, in application

  return application_unproxied(environ, start_response)

File: "/opt/bitnami/odoo/odoo/service/wsgi_server.py", line 117, in application_unproxied

  result = odoo.http.root(environ, start_response)

File: "/opt/bitnami/odoo/odoo/http.py", line 1287, in __call__

  return self.dispatch(environ, start_response)

File: "/opt/bitnami/odoo/odoo/http.py", line 1257, in __call__

  return self.app(environ, start_wrapped)

File: "/opt/bitnami/odoo/venv/lib/python3.6/site-packages/werkzeug/wsgi.py", line 766, in __call__

  return self.app(environ, start_response)

File: "/opt/bitnami/odoo/odoo/http.py", line 1457, in dispatch

  result = ir_http._dispatch()

File: "/opt/bitnami/odoo/odoo/addons/website/models/ir_http.py", line 172, in _dispatch

  response = super(Http, cls)._dispatch()

File: "/opt/bitnami/odoo/odoo/addons/auth_signup/models/ir_http.py", line 19, in _dispatch

  return super(Http, cls)._dispatch()

File: "/opt/bitnami/odoo/odoo/addons/web_editor/models/ir_http.py", line 21, in _dispatch

  return super(IrHttp, cls)._dispatch()

File: "/opt/bitnami/odoo/odoo/addons/utm/models/ir_http.py", line 29, in _dispatch

  response = super(IrHttp, cls)._dispatch()

File: "/opt/bitnami/odoo/odoo/addons/http_routing/models/ir_http.py", line 519, in _dispatch

  result = super(IrHttp, cls)._dispatch()

File: "/opt/bitnami/odoo/odoo/addons/base/models/ir_http.py", line 234, in _dispatch

  result = request.dispatch()

File: "/opt/bitnami/odoo/odoo/http.py", line 669, in dispatch

  result = self._call_function(**self.params)

File: "/opt/bitnami/odoo/odoo/http.py", line 350, in _call_function

  return checked_call(self.db, *args, **kwargs)

File: "/opt/bitnami/odoo/odoo/service/model.py", line 94, in wrapper

  return f(dbname, *args, **kwargs)

File: "/opt/bitnami/odoo/odoo/http.py", line 339, in checked_call

  result = self.endpoint(*a, **kw)

File: "/opt/bitnami/odoo/odoo/http.py", line 915, in __call__

  return self.method(*args, **kw)

File: "/opt/bitnami/odoo/odoo/http.py", line 515, in response_wrap

  response = f(*args, **kw)

File: "/opt/bitnami/odoo/odoo/addons/bus/controllers/main.py", line 40, in poll

  return self._poll(request.db, channels, last, options)

File: "/opt/bitnami/odoo/odoo/addons/mail/controllers/bus.py", line 32, in _poll

  return super(MailChatController, self)._poll(dbname, channels, last, options)

File: "/opt/bitnami/odoo/odoo/addons/bus/controllers/main.py", line 28, in _poll

  return dispatch.poll(dbname, channels, last, options)

File: "/opt/bitnami/odoo/odoo/addons/bus/models/bus.py", line 136, in poll

  event.wait(timeout=timeout)

File: "/opt/bitnami/python/lib/python3.6/threading.py", line 551, in wait

  signaled = self._cond.wait(timeout)

File: "/opt/bitnami/python/lib/python3.6/threading.py", line 299, in wait

  gotit = waiter.acquire(True, timeout)