** 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. + + [Expected result] + ubuntu-drivers takes seconds to run, not minutes. + + + [Steps to reproduce] + 1. Run 'time ubuntu-drivers list' several times + 2. observe the time + + [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. + + [Test plan] + 1. Run 'time ubuntu-drivers list' several times + the test should take mere seconds instead of tens of seconds or even minutes + + + [Where problems could occur] + 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
