Answers two review notes on the concurrent Tier A runner with measurements
instead of code changes:
- Two cores stay serial. Two in flight would give each project one Jest
worker, which runs Jest in-band; on a 2-core / 7 GB container ui-playback
and web ran out of their 2 GiB default heap. With a 4 GiB heap it passed
about 15% faster on a warm cache for 1.2 GiB more peak memory. CI runs on
4 cores. A test pins that the defaults never drop to one worker.
- Per-project output buffering is bounded in practice: a big project with
every test failing printed 1.8 MB while its Jest process peaked at 850 MB.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
