touch-packages team mailing list archive

[Marcus Tomlinson <marcus.tomlinson@xxxxxxxxxxxxx>]

Public bug reported:

Some causes ruled out:

1. OA in scopes can't be to blame as I have tested with and without it
enabled, and with and without it present in the code
(https://bugs.launchpad.net/ubuntu/+source/unity-scopes-
api/+bug/1392615/comments/4).

2. Location can't be blamed either (for the same reasons as above, as
well as removing location service usage from the shell plugin itself).

3. When profiling the QML and C++ code, I saw no indication that the
shell plugin was doing anything process intensive enough to cause any
hold up. In fact, it seems to be doing a pretty good job handling calls
from the UI thread asynchronously.


Observations made when profiling unity8:

1. The QML ListView component updates its current item index when the
next item reaches half-way across the screen (therefore, in mid
animation between scopes). There doesn't look to be any serious blocking
actions taking place during the onIsCurrentChange, setActive, etc.
methods that I could find, but we should keep this in mind.

2. ResultsModel::data() seems to be called constantly while scrolling a
scope up and down. I assume this should only be called once per result
item (This doesn't explain the horizontal scrolling lag, but it may
explain some vertical lag).

3. If you pull down to refresh any scope, then continuously move the
dash left and right, the dash movement is smooth until results start
showing up in the scope, at which point you see a lag as they appear.
The lag observed here is almost definitely the same lag we see when
scrolling through scopes (jittering as results start to pop up in scopes
as they populate).

(NOTE: All of the above points were observed with and without the latest
unity8 performance fixes in rtm silo 8)

** Affects: unity8 (Ubuntu)
     Importance: Undecided
         Status: New

-- 
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/1395994

Title:
  UI lags when scrolling through favorited scopes

Status in “unity8” package in Ubuntu:
  New

Bug description:
  Some causes ruled out:

  1. OA in scopes can't be to blame as I have tested with and without it
  enabled, and with and without it present in the code
  (https://bugs.launchpad.net/ubuntu/+source/unity-scopes-
  api/+bug/1392615/comments/4).

  2. Location can't be blamed either (for the same reasons as above, as
  well as removing location service usage from the shell plugin itself).

  3. When profiling the QML and C++ code, I saw no indication that the
  shell plugin was doing anything process intensive enough to cause any
  hold up. In fact, it seems to be doing a pretty good job handling
  calls from the UI thread asynchronously.

  
  Observations made when profiling unity8:

  1. The QML ListView component updates its current item index when the
  next item reaches half-way across the screen (therefore, in mid
  animation between scopes). There doesn't look to be any serious
  blocking actions taking place during the onIsCurrentChange, setActive,
  etc. methods that I could find, but we should keep this in mind.

  2. ResultsModel::data() seems to be called constantly while scrolling
  a scope up and down. I assume this should only be called once per
  result item (This doesn't explain the horizontal scrolling lag, but it
  may explain some vertical lag).

  3. If you pull down to refresh any scope, then continuously move the
  dash left and right, the dash movement is smooth until results start
  showing up in the scope, at which point you see a lag as they appear.
  The lag observed here is almost definitely the same lag we see when
  scrolling through scopes (jittering as results start to pop up in
  scopes as they populate).

  (NOTE: All of the above points were observed with and without the
  latest unity8 performance fixes in rtm silo 8)

To manage notifications about this bug go to:
https://bugs.launchpad.net/ubuntu/+source/unity8/+bug/1395994/+subscriptions