I "think" I found the culprit. http://bazaar.launchpad.net/~phablet-team/platform-api/trunk/view/331/src/ubuntu/application/common/application/sensors/service.cpp#L84
It seems the old feedback plugin was async (see https://code.launchpad.net/~kalikiana/qtubuntu- sensors/feedback/+merge/183456 with https://code.launchpad.net/~kalikiana/qtubuntu- sensors/feedback/+merge/183456/comments/431467 and the reply https://code.launchpad.net/~kalikiana/qtubuntu- sensors/feedback/+merge/183456/comments/431975 ) while the new one is using synchronous dbus calls. http://bazaar.launchpad.net/~phablet-team/platform-api/trunk/view/331/src/ubuntu/application/common/application/sensors/service.cpp#L84 For some reason it seems the dbus service in my case stopped responding to the requests to enable the vibrator, and that was causing the UI thread to block waiting on a reply on dbus. ** Description changed: Krillin, rc-proposed/bq_aquaris.en r422 + + 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 ** Also affects: platform-api (Ubuntu) Importance: Undecided Status: New ** No longer affects: ubuntu-ui-toolkit (Ubuntu) -- You received this bug notification because you are a member of Ubuntu SDK bug tracking, which is subscribed to ubuntu-ui-toolkit in Ubuntu. https://bugs.launchpad.net/bugs/1620553 Title: [Krillin] Taps are delayed by 1-2seconds, although gestures are not. Keyboard is thus unusable Status in platform-api package in Ubuntu: New Bug description: Krillin, rc-proposed/bq_aquaris.en r422 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/ubuntu/+source/platform-api/+bug/1620553/+subscriptions -- Mailing list: https://launchpad.net/~ubuntu-sdk-bugs Post to : ubuntu-sdk-bugs@lists.launchpad.net Unsubscribe : https://launchpad.net/~ubuntu-sdk-bugs More help : https://help.launchpad.net/ListHelp
