Telemetry benchmarks start scrolling before page is initialized |
|||
Issue descriptionI noted this while investigating why my patch in https://codereview.chromium.org/2365793002/ regressed the scheduler.tough_scheduling_cases benchmark in issue 650029. It turns out that benchmark starts scrolling before the page is completely initialized. This means that the ScrollBegin comes in and we target the current outer viewport scroll layer. After this, the active tree receives a new outer viewport causing us to lose the current scrolling layer and thus dropping the scrolls on the floor. Previously, we'd target the inner viewport which doesn't change so this wasn't a problem. Really though, there's no reason to treat the viewport as special. We shouldn't start sending events until the active tree is fully initialized.
,
Oct 5 2016
All the layers for the page are ready to scroll on the compositor's active tree. Currently, it could be that we wait until the main thread/Blink says the page is loaded, but we start sending scroll events to the compositor before we've committed those changes. This means we could be scrolling layers belonging to the previous page and could be a source of flakiness (in addition to making my change above more painful).
,
Oct 5 2016
So you suggest we wait for things like DOMContentLoaded?
,
Oct 5 2016
I'm not sure what the solution is yet, but I doubt there's a web-API available for this. We'd likely need to add a private hook somewhere or some small delay, I'll investigate.
,
Oct 7 2016
,
Oct 11 2016
The following revision refers to this bug: https://chromium.googlesource.com/chromium/src.git/+/eb735dcc1ff10e3c333345bd0902c1baed793543 commit eb735dcc1ff10e3c333345bd0902c1baed793543 Author: catapult-deps-roller <catapult-deps-roller@chromium.org> Date: Tue Oct 11 17:06:48 2016 Roll src/third_party/catapult/ a1fdeaa2c..840e04295 (2 commits). https://chromium.googlesource.com/external/github.com/catapult-project/catapult.git/+log/a1fdeaa2c402..840e04295a00 $ git log a1fdeaa2c..840e04295 --date=short --no-merges --format='%ad %ae %s' 2016-10-11 nednguyen Output error message & exit gracefully when telemetry cannot find the browser 2016-10-11 bokan Wait a frame before finishing navigation BUG= 652905 CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.android:android_optional_gpu_tests_rel TBR=catapult-sheriff@chromium.org Review-Url: https://codereview.chromium.org/2407323002 Cr-Commit-Position: refs/heads/master@{#424463} [modify] https://crrev.com/eb735dcc1ff10e3c333345bd0902c1baed793543/DEPS
,
Oct 21 2016
|
|||
►
Sign in to add a comment |
|||
Comment 1 by nedngu...@google.com
, Oct 5 2016