WebRender Q1 2020

The purpose of this document is to highlight our priorities for WebRender in Q1 of 2020

Where have we shipped WebRender?

For a list of the various places we have shipped WebRender, see: https://wiki.mozilla.org/Platform/GFX/WebRender_Where

Under 'compositor usage' you can see the % of Windows users who are using WebRender: https://firefoxgraphics.github.io/telemetry/#view=windows-features

Tracking

We are currently using GitHub's project feature to track our roadmaps

• Android Specific: https://github.com/orgs/FirefoxGraphics/projects/6
• WebRender quarterly breakdown: https://github.com/orgs/FirefoxGraphics/projects/4
• WebRender overall roadmap: https://github.com/orgs/FirefoxGraphics/projects/1
  • Note: this will be re-worked at January All Hands, it is currently out-of-date

Core Priorities

Shipping WebRender

We want to keep shipping WebRender to as many targets as possible each quarter. Below is a list of releases in Q1 and what we are aiming to ship per release:

• 72 (Jan 7)
  • WR on Android for Pixels 2, 3, 2XL and 3XL
    • https://bugzilla.mozilla.org/show_bug.cgi?id=1600133
• 73 (Feb 11)
  • WR for Nvidia laptops with small screen (update - we were going to target this for 72, moving to 73)
    • https://bugzilla.mozilla.org/show_bug.cgi?id=1566875
      • We are going to limit this to recent driver: https://bugzilla.mozilla.org/show_bug.cgi?id=1611193
• 74 (March 10)
  • Aiming to target shipping DirectComposition for 74 or 75 (pending fall-out bugs)
  • Update March 2: we are moving this to 75 due to bugs

As part of this effort, we will need to monitor and fix any critical correctness or perf bugs that appear that could potentially block shipping those targets. Here is a list of metabugs where we will track any key bugs we will be monitoring for this effort:

• WR-72: https://mzl.la/2pUB7wl
• WR-73: https://mzl.la/2JvXrmT
• WR-74: https://mzl.la/2PzWqfJ

Perf Infrastructure/Unblock more Intel

In Q4, we made good strides on the core work we needed to complete in order to improve performance so that we can ship on more Intel hardware, Intel laptops specifically.

Our first focus is on shipping our Windows Compositor (DirectComposition) work:

• https://bugzilla.mozilla.org/show_bug.cgi?id=1575902

We will address any fallout bugs that happen as a result of landing that code, re-measure performance and assess if there are any other tasks we should do this quarter.

Software WebRender

We want to make progress on our plans for a software fallback for WebRender. We are currently in the midst of testing our various options. Our goals are as follows:

• Perform the testing and investigation necessary to make a decision on path forward
• After that, we will detail out our first milestone for SW WR
• March milestone:
  • Once SW WR is in tree, run Wrench reftests and start fixing failures
• Feb milestone for SW WR: https://bugzilla.mozilla.org/show_bug.cgi?id=1612941

Useful tracking bugs:

• Bug for initial SW-WR perf investigations: https://bugzilla.mozilla.org/show_bug.cgi?id=1548395
• Metabug for tracking SW-WR: https://bugzilla.mozilla.org/show_bug.cgi?id=sw-wr

WR Perf

We want to make progress against any priority performance issues we deem necessary in Q1

Those items will be tagged as WR-Perf and tracked here in our quarterly project breakdown: https://github.com/orgs/FirefoxGraphics/projects/4

We are also performing regular triage of perf-specific bugs, those are visible: https://wiki.mozilla.org/Platform/GFX/perf_triage