Document how to run the browser suites in parallel and sharded, with the
measured times, and what keeps specs stable beside each other: wait for
a rendering frame, a response or a visible state, never for time.
With b665aa6 the full workflows suite passed on chromium, touch, firefox
and webkit with 8 workers, each test 3 times (6132 passed, 0 failed,
24 minutes), and once at CI size (docker --cpus=4, 3 workers: 2044
passed, 25.5 minutes).
The npm download cache removed the npm ci stall: 0 to 2 s in every job
of run 39722172529, against about 300 s in most jobs before. The
workflow's timing comment now records that run; the whole workflow took
8m54s against about 33 minutes before sharding. Shard imbalance (shard 1
carries the concept-comparison specs) is documented, not tuned.
Vito Sansevero
cbc8a61b1d