Cinder backing file too small for Tempest tests

[Peter Penchev]

Hi,

Thanks a lot for working on devstack!

Recently there have been many spurious test failures in the OpenStack Zuul checks and gate tests caused by the tempest-full scenario trying to run several volume- and snapshot-related tests in parallel. It turns out that the default Cinder backing file size in devstack (1025M) is not enough for all the snapshots and volumes that may be created if the test run happens to execute several of those at once.

This has not been a problem before because devstack-gate contains a change (https://review.openstack.org/#/c/35129/) that increases the size of the Cinder backing file to 24G, thus providing enough space. However, recent runs in the OpenStack test infrastructure do not always use devstack-gate, but run devstack directly from Ansible without overriding the backing file size.

It was suggested that the increase of the default file size should be made in devstack to also help others who run tempest through devstack in their local environments. Attached is the patch from the proposed https://review.openstack.org/#/c/533312 that increases the file size to 24G.

Thanks in advance for any comments, and keep up the great work!

Best regards,
Peter

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/533312
Committed: https://git.openstack.org/cgit/openstack-dev/devstack/commit/?id=6bcd8cad16c39dd8596d654eb4587e848d0db1fe
Submitter: Zuul
Branch: master

commit 6bcd8cad16c39dd8596d654eb4587e848d0db1fe
Author: Peter Penchev <email address hidden>
Date: Fri Jan 12 23:49:04 2018 +0200

    Bump the Cinder LVM backing file size to 24Gb.

    This follows a change made to devstack-gate in commit 841ebc3 to allow
    tempest to succeed even if it happens to run several volume tests in
    parallel. Right now it's possible for a tempest-full test (run without
    devstack-gate) to fail with an "Insufficient free virtual space" error in
    the cinder-scheduler log.

    Suggested by: Clark Boylan <email address hidden>
    Closes-Bug: 1743597
    Change-Id: I16ccb9976d1bc7c9f56a6a4d73e35042a5867ef9

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: stable/pike
Review: https://review.openstack.org/559741

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/559741
Committed: https://git.openstack.org/cgit/openstack-dev/devstack/commit/?id=1ff70fd807fffbce6ded63828e1ae4c5fd08b338
Submitter: Zuul
Branch: stable/pike

commit 1ff70fd807fffbce6ded63828e1ae4c5fd08b338
Author: Peter Penchev <email address hidden>
Date: Fri Jan 12 23:49:04 2018 +0200

    Bump the Cinder LVM backing file size to 24Gb.

    This follows a change made to devstack-gate in commit 841ebc3 to allow
    tempest to succeed even if it happens to run several volume tests in
    parallel. Right now it's possible for a tempest-full test (run without
    devstack-gate) to fail with an "Insufficient free virtual space" error in
    the cinder-scheduler log.

    Suggested by: Clark Boylan <email address hidden>
    Closes-Bug: 1743597
    Change-Id: I16ccb9976d1bc7c9f56a6a4d73e35042a5867ef9
    (cherry picked from commit 6bcd8cad16c39dd8596d654eb4587e848d0db1fe)