@Albert and @Kevin: please find the full log attached. I had a quick look, the main thread is chocking on the polish phase. So it seems a layout performance problem, unless we're using Canvas in the QML code (Canvas does the rendering in the polish method, iirc)
Examples from the log: 3.4 seconds polish phase here qt.scenegraph.renderloop: update from item QQuickView(0x7a98a0) qt.scenegraph.renderloop: update from item QQuickView(0x7a98a0) qt.scenegraph.time.renderloop: Frame prepared with 'threaded' renderloop, polish=3479, lock=0, blockedForSync=78, animations=24 - (on Gui thread) QQuickView(0x7a98a0) qt.scenegraph.time.glyph: distancefield: 29 glyphs prepared in 23ms, rendering=15, upload=8 Pre-populating scope "com.canonical.elpais_ELPAIS" qt.scenegraph.time.texture: atlastexture uploaded in: 0ms (94x20) or 1.3sec polish phase qt.scenegraph.renderloop: update from item QQuickView(0x7a98a0) <Unknown File>:138:1: QML Label: Binding loop detected for property "height" qt.scenegraph.time.renderloop: Frame prepared with 'threaded' renderloop, polish=1297, lock=0, blockedForSync=40, animations=119 - (on Gui thread) QQuickView(0x7a98a0) flushUpdates: "com.canonical.scopes.engadget_engadget" #results = 25 finalize: true Adding # 25 results to category "root" qt.scenegraph.renderloop: update from item QQuickView(0x7a98a0) or 1.285sec polish phase qt.scenegraph.renderloop: update from item QQuickView(0x7a98a0) qt.scenegraph.renderloop: - lock for sync qt.scenegraph.renderloop: - wait for sync qt.scenegraph.renderloop: (RT) WM_RequestSync qt.scenegraph.renderloop: (RT) --- done processEventsAndWaitForMore() qt.scenegraph.renderloop: (RT) syncAndRender() qt.scenegraph.renderloop: (RT) - updatePending, doing sync qt.scenegraph.renderloop: (RT) sync() qt.scenegraph.renderloop: (RT) sceneGraphChanged qt.scenegraph.renderloop: (RT) - sync complete, waking Gui qt.scenegraph.renderloop: (RT) - rendering started qt.scenegraph.renderloop: - unlock after sync qt.scenegraph.time.renderloop: Frame prepared with 'threaded' renderloop, polish=1285, lock=0, blockedForSync=32, animations=0 - (on Gui thread) QQuickView(0x7a98a0) flushUpdates: "com.canonical.scopes.reddit" #results = 70 finalize: true Last result index= 30 category "posts" qt.scenegraph.renderloop: update from item QQuickView(0x7a98a0) qt.scenegraph.renderloop: - posting update Added # 70 results (called with 100 ), current results#= 100 See the 3+ secs polish time, that's the kind of freezes I'm seeing. There are also multiple 1+sec and 0.1secs+ of polish times in the log. There are also many examples of <Unknown File>:128:1: QML Label: Binding loop detected for property "height" and <Unknown File>:121:2: QML Icon: Binding loop detected for property "width" Those could be disturbing the polish phase, although they're likely not the cause of *all* the freezes. ** Attachment added: "unity8-dash qt.scenegraph.* log" https://bugs.launchpad.net/ubuntu/+source/unity8/+bug/1384374/+attachment/4686325/+files/unity8-dash.log -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1384374 Title: Dash pauses/stutters during scope switching left/right To manage notifications about this bug go to: https://bugs.launchpad.net/canonical-devices-system-image/+bug/1384374/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs