OK, I think I understand this now. Maybe. The problem is that the unity8 nested server BufferStream has not been assigned a frame_clock (doesn't know what monitor to sync to), so it's defaulting to unthrottled behaviour even though the swap interval is 1.
This problem should probably occur with any nested server. However it was not noticed in testing because it will only be perceptible if your nested server is also slow enough that its rendering period aliases visibly with the physical screen. ** Changed in: mir/0.26 Status: Confirmed => Triaged ** Changed in: unity8 (Ubuntu) Status: Confirmed => Invalid ** Changed in: canonical-devices-system-image Status: Confirmed => Triaged -- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to unity8 in Ubuntu. https://bugs.launchpad.net/bugs/1661128 Title: [regression] Unity8 stutters constantly (like half frame rate) Status in Canonical System Image: Triaged Status in Mir: In Progress Status in Mir 0.26 series: Triaged Status in unity8 package in Ubuntu: Invalid Bug description: Unity8 stutters constantly (like half frame rate) on a high-end desktop. This regression only happened recently, perhaps due to the introduction of Mir 0.26.0. Surprisingly though, using the same Mir release I can start a demo server on another VT and everything is silky-smooth. The problem only seems to occur with Unity8. To manage notifications about this bug go to: https://bugs.launchpad.net/canonical-devices-system-image/+bug/1661128/+subscriptions -- Mailing list: https://launchpad.net/~touch-packages Post to : touch-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~touch-packages More help : https://help.launchpad.net/ListHelp