Thanks Pat telling me how to reproduce it. I have reproduced it. I am trying to figuring out the reason and at the same time I wrote to James for help.
-- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to platform-api in Ubuntu. https://bugs.launchpad.net/bugs/1620553 Title: OSK becomes unusable as taps are delayed by 1-2 seconds and vibration doesn't occur any more (although gestures continue to work) Status in Canonical System Image: In Progress Status in platform-api package in Ubuntu: In Progress Status in usensord package in Ubuntu: In Progress Bug description: Krillin, rc-proposed/bq_aquaris.en r422 TEST CASE: 1. Create to alarms that'll trigger at the same time 2. Wait until they go off 3. Dismiss the alarms 4. Verify that there is still haptic feedback and OSK is still responsive ACTUAL RESULT Step 4 fails. UPDATE: see comment #5, it turns out it's the haptics plugin doing SYNC dbus calls and blocking the UI thread when the dbus service does not reply or the replies come with a big delay Description: All at once taps have become incredibly delayed, by 1 or 2 secs. Gestures still work ok, no delay there. Swiping the greeter -> no delay. Tapping numbers to input code on the greeter --> 2 secs delay. Even though both are parts of unity8. So it doesn't seem to only be a problem of unity8 clients, but also unity8 itself. I have no idea why horizontal/vertical swipes would be unaffected, though. The virtual keyboard is also completely unusable because of the huge delay that each tap has. Also noticed that the vibration is gone, taps don't trigger vibration anymore. Webview also seemed to be unaffected by the delays (although I'm not entirely sure, the bug is now gone) I also restarted unity8 and unity8-dash with Mir input logging enabled. That showed that the touch events were being delivered as expected, no delay. restart unity8 MIR_CLIENT_INPUT_RECEIVER_REPORT=log and restart unity8-dash MIR_CLIENT_INPUT_RECEIVER_REPORT=log Restarting lightdm (that forces the restart of unity-system- compositor) fixed the issue. Additional info: I had Mir touchspots visualization enabled, which are known to cause more stuttering, but I think they're unlikely to be the cause of this bug, I had them enabled for 2 weeks and haven't noticed any problem like this before. This is the log from a tap on an icon in the shell: [2016-09-06 10:52:51.876400] <DEBUG> input-receiver: Received event:touch_event(when=54593678129000 (6.030520ms ago), from=3, touch = {{id=0, action=down, tool=finger, x=426.211, y=292.695, pressure=0.85098, major=19.963, minor=0, size=19.963}, modifiers=1) [2016-09-06 10:52:51.953821] <DEBUG> input-receiver: Received event:touch_event(when=54593751953000 (9.709366ms ago), from=3, touch = {{id=0, action=change, tool=finger, x=426.211, y=292.695, pressure=0.843137, major=19.963, minor=0, size=19.963}, modifiers=1) [2016-09-06 10:52:51.954343] <DEBUG> input-receiver: Received event:touch_event(when=54593761256000 (0.958751ms ago), from=3, touch = {{id=0, action=up, tool=finger, x=426.211, y=292.695, pressure=0.843137, major=19.963, minor=0, size=19.963}, modifiers=1) SEE VIDEO ATTACHMENT BELOW To manage notifications about this bug go to: https://bugs.launchpad.net/canonical-devices-system-image/+bug/1620553/+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