[Bug 1850754] Please test proposed package

[Corey Bryant]

Hello Dariusz, or anyone else affected,

Accepted ceph into train-proposed. The package will build now and be
available in the Ubuntu Cloud Archive in a few hours, and then in the
-proposed repository.

Please help us by testing this new package. To enable the -proposed
repository:

  sudo add-apt-repository cloud-archive:train-proposed
  sudo apt-get update

Your feedback will aid us getting this update out to other Ubuntu users.

If this package fixes the bug for you, please add a comment to this bug,
mentioning the version of the package you tested, and change the tag
from verification-train-needed to verification-train-done. If it does
not fix the bug for you, please add a comment stating that, and change
the tag to verification-train-failed. In either case, details of your
testing will help us make a better decision.

Further information regarding the verification process can be found at
https://wiki.ubuntu.com/QATeam/PerformingSRUVerification . Thank you in
advance!

** Tags added: verification-train-needed

-- 
You received this bug notification because you are a member of Ubuntu
OpenStack, which is subscribed to Ubuntu Cloud Archive.
https://bugs.launchpad.net/bugs/1850754

Title:
  ceph-volume lvm list is O(n^2)

Status in Ceph:
  Unknown
Status in Ubuntu Cloud Archive:
  Fix Committed
Status in Ubuntu Cloud Archive queens series:
  Fix Committed
Status in Ubuntu Cloud Archive rocky series:
  New
Status in Ubuntu Cloud Archive stein series:
  New
Status in Ubuntu Cloud Archive train series:
  Fix Committed
Status in ceph package in Ubuntu:
  Fix Released
Status in ceph source package in Bionic:
  Fix Committed
Status in ceph source package in Disco:
  New
Status in ceph source package in Eoan:
  Fix Committed

Bug description:
  [Impact]
  ceph-volume lvm calls take too much time and the time grows exponentially.
  A simple call may take several minutes depending on the LV configuration.

  [Test Case]
  1. Create a setup with a large number of disks and logical volumes (e.g. 24)
  2. Call ceph-volume lvm list for one of the disks.
  3. Wait for the call to finish.

  [Regression Potential]
  Patch introduces LV caching, so changing LVs while ceph-volume is running may lead to race conditions.

  [Other Info]
  Original bug description:
   
   * Anything else you think is useful to include
   * Anticipate questions from users, SRU, +1 maintenance, security teams and the Technical Board
   * and address these questions in advance

  ceph-volume lvm list calls take very long time due to the fact it has
  been implemented with O(n^2). This leads to unproportionally long
  execution time taking under consideration the fact that no complex
  computation is needed.

  Steps to reproduce:
  1. Create a setup with a large number of disks and logical volumes (e.g. 24)
  2. Call ceph-volume lvm list for one of the disks.
  3. Wait for the call to finish.

  Expected result:
  Call is executed within seconds at most.

  Actual result:
  Call may take even minutes in some circumstances (large number of disks, some OSDs stopped).

To manage notifications about this bug go to:
https://bugs.launchpad.net/ceph/+bug/1850754/+subscriptions