After a little bit of self-education, I found that /proc/sys/kernel/random/entropy_avail was below 100, which is probably a good explanation for my problem. A good value would have four digits, it seems.

My Devstack host runs Ubuntu 18, and I am now trying the rngd-tools5 package to improve the entropy situation. Since this is a test system, I am not so concerned about random number quality.

In short, the problem seems to be solved, but if anybody has additional comments, I would be interested to hear them.

Bernd

I run Stein Devstack in a virtual machine. Occasionally, openstack client commands take minutes to complete, which didn't happen at earlier releases, and which is rather annoying. The delay seems to take place at an early stage: Even when I forget to set the OS_* environment, it takes minutes until I am told that the request requires authentication.

Interrupting the command, the stack trace confirms this (as a side remark, it also takes a long while until my ^C is processed):

Traceback (most recent call last):
  File "/usr/local/bin/openstack", line 7, in <module>
    from openstackclient.shell import main
  File "/usr/local/lib/python2.7/dist-packages/openstackclient/shell.py", line 22, in <module>
    from osc_lib.api import auth
  File "/usr/local/lib/python2.7/dist-packages/osc_lib/api/auth.py", line 19, in <module>
    from keystoneauth1.loading import base
  File "/usr/local/lib/python2.7/dist-packages/keystoneauth1/loading/__init__.py", line 13, in <module>
    from keystoneauth1.loading import adapter
  File "/usr/local/lib/python2.7/dist-packages/keystoneauth1/loading/adapter.py", line 13, in <module>
    from keystoneauth1 import adapter
  File "/usr/local/lib/python2.7/dist-packages/keystoneauth1/adapter.py", line 17, in <module>
    from keystoneauth1 import session
  File "/usr/local/lib/python2.7/dist-packages/keystoneauth1/session.py", line 25, in <module>
    import requests
  File "/usr/local/lib/python2.7/dist-packages/requests/__init__.py", line 95, in <module>
    from urllib3.contrib import pyopenssl
  File "/usr/local/lib/python2.7/dist-packages/urllib3/contrib/pyopenssl.py", line 48, in <module>
    from cryptography.hazmat.backends.openssl import backend as openssl_backend
  File "/usr/local/lib/python2.7/dist-packages/cryptography/hazmat/backends/openssl/__init__.py", line 7, in <module>
    from cryptography.hazmat.backends.openssl.backend import backend
  File "/usr/local/lib/python2.7/dist-packages/cryptography/hazmat/backends/openssl/backend.py", line 2419, in <module>
    backend = Backend()
  File "/usr/local/lib/python2.7/dist-packages/cryptography/hazmat/backends/openssl/backend.py", line 119, in __init__
    self.activate_osrandom_engine()
  File "/usr/local/lib/python2.7/dist-packages/cryptography/hazmat/backends/openssl/backend.py", line 163, in activate_osrandom_engine
    with self._get_osurandom_engine() as e:
  File "/usr/lib/python2.7/contextlib.py", line 17, in __enter__
    return self.gen.next()
  File "/usr/local/lib/python2.7/dist-packages/cryptography/hazmat/backends/openssl/backend.py", line 146, in _get_osurandom_engine
    res = self._lib.ENGINE_init(e)
KeyboardInterrupt

My wild speculation is that the delay has something to do with obtaining a random number, which can be a problem on virtual machines due to their lack of entropy. My knowledge in this area is paper-thin, though. And I wonder what happens to all the Devstacks used in CI?

Thus my questions: Is the delay really caused by my running the cloud on a VM? What can I do to improve this?

Thanks,

Bernd