** Description changed: + [Impact] + Some basic operations on ubuntu-drivers are extremely slow (> 1mn) and CPU-intensive, to the point that users might think it broken. + + Examples of such operations are + ubuntu-drivers list + ubuntu-drivers list-oem + + Both of those operations are used in subiquity. While the performance + hit there might not be too noticeable due to parallelism with other + steps of the install, it's still fairly bad. + + And of course users of both the ubuntu-drivers CLI and the software- + properties panel GUI feel the impact in full. + + [Proposed fix] + + https://github.com/canonical/ubuntu-drivers-common/pull/116 + + There is an issue when trying to compute a stable key to cache the + results of a costly computation (modalias mapping), resulting in a + write-only cache. + + The fix is to remove the cache entirely, expose the computation method + as a new public API, and let the caller optionally provide the + previously cached value. + + Regression risks are minimal: for all the use cases listed above, the + call sites are within ubuntu-drivers-common and have been inspected for + correctness of hoisting the modalias mapping out of the loop. Any other + caller of the changed API doesn't need to be changed as the new argument + is optional. The removal of the cache is essentially a NOP since cached + values weren't retrieved anyway due to the original bug. + + [Original report] Looking for drivers is extremely slow. Verified to exist on multiple systems. ---------------- $ time ubuntu-drivers list nvidia-driver-560-open, (kernel modules provided by linux-modules-nvidia-560-open-generic-hwe-24.04) nvidia-driver-560, (kernel modules provided by linux-modules-nvidia-560-generic-hwe-24.04) real 1m48.680s user 0m26.984s sys 1m21.665s ----------------
-- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/2092601 Title: ubuntu-drivers list - Extremely slow To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/ubuntu-drivers-common/+bug/2092601/+subscriptions -- ubuntu-bugs mailing list [email protected] https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
