Comment 31 for bug 1896463

Reviewed: https://review.opendev.org/c/openstack/nova/+/841288
Committed: https://opendev.org/openstack/nova/commit/e558aa2046b649696b69551657e5d429e8117427
Submitter: "Zuul (22348)"
Branch: stable/train

commit e558aa2046b649696b69551657e5d429e8117427
Author: Balazs Gibizer <email address hidden>
Date: Thu Sep 24 15:04:21 2020 +0200

    Reproduce bug 1896463 in func env

    There is a race condition between the rebuild and the
    _update_available_resource periodic task on the compute. This patch adds
    a reproducer functional test. Unfortunately it needs some injected sleep
    to make the race happen in a stable way. This is suboptimal but only
    adds 3 seconds of slowness to the test execution.

    Conflicts:
      nova/tests/functional/regressions/test_bug_1896463.py due to
      I84c58de90dad6d86271767363aef90ddac0f1730 and
      I8c96b337f32148f8f5899c9b87af331b1fa41424 is not in stable/train.
      Also I had to make the test code python 2 compatible.

    Change-Id: Id0577bceed9808b52da4acc352cf9c204f6c8861
    Related-Bug: #1896463
    (cherry picked from commit 3f348602ae4a40c52c7135b2cb48deaa6052c488)
    (cherry picked from commit d768cdbb88d0b0b3ca38623c4bb26d5eabdf1596)
    (cherry picked from commit 02114a9d7f2e8b62d3a7091ca3fde251dfffa860)