Public bug reported: [Impact]
* Every ceph-volume list lvm <device> call invokes blkid for numerous PARTUUIDs. For some setups with many slower IO devices this can make this call to run for minutes without any actual justification for that. In fact, the upstream ceph approach changed in this matter and post-bionic releases already have ceph-volume that does not invoke blkid at all in this context making the call much faster. Please examine the attached ceph-volume.log fragment for a ceph-volume call, the accumulated blkid calls take around 1 min 7 s. [Test Case] * Setup a ceph-osd with numerous block devices with long access time for blkid. * Run time ceph-volume --log-path ceph-volume.log --log-level debug lvm list <device> on one of them and check the log to see that most of the execution time is consumed by blkid calls. [Where problems could occur] * Although a potential fix does not introduce any changes to how ceph- volume is used any automation depending on ceph-volume log parsing may notice a change. [Other Info] * The fix to this is available for Focal and beyond. * Xenial is not affected due to lack of ceph-volume in its ceph release. ** Affects: ceph (Ubuntu) Importance: Undecided Status: Fix Released ** Affects: ceph (Ubuntu Bionic) Importance: Medium Assignee: Dariusz Gadomski (dgadomski) Status: In Progress ** Tags: sts -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1908375 Title: ceph-volume lvm list <device> calls blkid numerous times for differrent devices To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/ceph/+bug/1908375/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs