The display-compositor currently sends presentation-feedback to clients only for the frames where the client explicitly requests for it. Instead of this, we would like to send the presentation time to the client for all frames, so that the client has better information about how it is doing in terms of performance.
Turning on presentation-feedback for a lot of frames has previously caused regressions [1], so we need to do this cautiously and in small steps. I think we can take the following sub-steps to turn this on:
. Turn on presentation-time for each frame from OutputSurface back to Display.
. Always send the presentation-times back to client.
. Report the presentation-times in telemetry tests and UMA.
. Cleanup of code no-longer needed (e.g. LayerTreeSettings::always_request_presentation_time etc.)
[1] https://bugs.chromium.org/p/chromium/issues/detail?id=851088#c5
Comment 1 by fsam...@chromium.org
, Sep 13