As of Beta 53, we still have 50-50 split of control and test. We have determined to re-organize the the control/test split to 10% control and 90% test.
The goal of 53 Beta and Release is to allow e10s to expand to all users, unless they have add-ons marked specifically MPC=False (not multiprocess compatible). See the full update from Shell, here.
e10s-multi is enabled as of Firefox 54 Nightly, now with 4 content processes enabled. We are on track for enabling e10s-multi with 4 content processes in Aurora. A plan for Beta 54 experiments are currently work in progress.
Our forecast for the engineering schedule tracks to being MVP as of 55 and we are working to uplift as much as possible to 54 with an eye toards shipping in 54 so long as we meet or exceed our release criteria.
[ON TRACK] E10s-Multi
The team is currently focused on correctness, measuring performance and memory, and Scaling to 4 Processes. You can read more about what this means in the e10s-multi wiki. Basically, we are working hard so multi can ride the trains.
The E10s-Multi plan is taking shape: our current forecast predicts that engineering MVP will be complete before the end of Firefox 55. We are currently 80% complete.
We have one hard dependency bug 1346247 we need to land before we can enable on Aurora, and one nice-to-have bug 1293277.
Determining what Beta experiment design will need to be and making sure any new engineering work required for the System Add-On is defined is currently in progress and should be complete by the end of March 24th.