Open Stack

Hi,

After a few tempest run I noticed slowdowns in the nova-api-os-compute
uwsgi  processes. I check the processes with py-spy and found that a lot
of process blocked on read(). Here is my py-spy output from one of my
nova-api-os-compute uwsgi process: http://paste.openstack.org/show/731677/

And the stack trace:

thread_id = Thread-2 filename = /usr/lib/python2.7/threading.py lineno =
774 function = __bootstrap line = self.__bootstrap_inner()
thread_id = Thread-2 filename = /usr/lib/python2.7/threading.py lineno =
801 function = __bootstrap_inner line = self.run()
thread_id = Thread-2 filename = /usr/lib/python2.7/threading.py lineno =
754 function = run line = self.__target(*self.__args, **self.__kwargs)
thread_id = Thread-2 filename =
/openstack/venvs/nova-17.0.4/lib/python2.7/site-packages/oslo_messaging/_drivers/amqpdriver.py
lineno = 382 function = poll line =
self.conn.consume(timeout=current_timeout)
thread_id = Thread-2 filename =
/openstack/venvs/nova-17.0.4/lib/python2.7/site-packages/oslo_messaging/_drivers/impl_rabbit.py
lineno = 1083 function = consume line = error_callback=_error_callback)
thread_id = Thread-2 filename =
/openstack/venvs/nova-17.0.4/lib/python2.7/site-packages/oslo_messaging/_drivers/impl_rabbit.py
lineno = 807 function = ensure line = ret, channel = autoretry_method()
thread_id = Thread-2 filename =
/openstack/venvs/nova-17.0.4/lib/python2.7/site-packages/kombu/connection.py
lineno = 494 function = _ensured line = return fun(*args, **kwargs)
thread_id = Thread-2 filename =
/openstack/venvs/nova-17.0.4/lib/python2.7/site-packages/kombu/connection.py
lineno = 570 function = __call__ line = return fun(*args,
channel=channels[0], **kwargs), channels[0]
thread_id = Thread-2 filename =
/openstack/venvs/nova-17.0.4/lib/python2.7/site-packages/oslo_messaging/_drivers/impl_rabbit.py
lineno = 796 function = execute_method line = method()
thread_id = Thread-2 filename =
/openstack/venvs/nova-17.0.4/lib/python2.7/site-packages/oslo_messaging/_drivers/impl_rabbit.py
lineno = 1068 function = _consume line =
self.connection.drain_events(timeout=poll_timeout)
thread_id = Thread-2 filename =
/openstack/venvs/nova-17.0.4/lib/python2.7/site-packages/kombu/connection.py
lineno = 301 function = drain_events line = return
self.transport.drain_events(self.connection, **kwargs)
thread_id = Thread-2 filename =
/openstack/venvs/nova-17.0.4/lib/python2.7/site-packages/kombu/transport/pyamqp.py
lineno = 103 function = drain_events line = return
connection.drain_events(**kwargs)
thread_id = Thread-2 filename =
/openstack/venvs/nova-17.0.4/lib/python2.7/site-packages/amqp/connection.py
lineno = 471 function = drain_events line = while not
self.blocking_read(timeout):
thread_id = Thread-2 filename =
/openstack/venvs/nova-17.0.4/lib/python2.7/site-packages/amqp/connection.py
lineno = 476 function = blocking_read line = frame =
self.transport.read_frame()
thread_id = Thread-2 filename =
/openstack/venvs/nova-17.0.4/lib/python2.7/site-packages/amqp/transport.py
lineno = 226 function = read_frame line = frame_header = read(7, True)
thread_id = Thread-2 filename =
/openstack/venvs/nova-17.0.4/lib/python2.7/site-packages/amqp/transport.py
lineno = 346 function = _read line = s = recv(n - len(rbuf))  # see note
above
thread_id = Thread-2 filename = /usr/lib/python2.7/ssl.py lineno = 643
function = read line = v = self._sslobj.read(len)

I am using nova 17.0.4.dev1, amqp (2.2.2), oslo.messaging (5.35.0),
kombu (4.1.0). I have 3 controller nodes. The openstack deployed by OSA
17.0.4.

I can reproduce the read() block if I click on "Log" in Horizon to see
the console outputs from one of my VM or run a tempest test:
tempest.api.compute.admin.test_hypervisor.HypervisorAdminTestJSON.test_get_hypervisor_uptime.

The nova-api response time increasing when more and more nova-api
processes get blocked at this read. Is it a normal behavior?

--- 
Regards,
Robert Varjasi
consultant at Component Soft Ltd.