Improves CI build performance

[NickSdot]

WIP

Results

f47a44e

Faster Windows CI through parallel builds/tests and overlapping database setup

Windows x64	Before	After	Improvement
Setup + build	10:53	3:22	69%
Tests	30:37	14:48	52%
Full job	41:55	18:48	55%

Cache hit rate: ~95%.

8e526f1

Benchmark checkout avoids downloading unnecessary historical file contents

Step	Before	After	Improvement
Benchmark checkout	~1:11	0:20	72%

d2b0d08

Keeps non-Windows compiler caches fresh

Before: the older the weekly cache, the lower the hit rate. 2026-07-27 was ~99% (0:30s) while 2026-08-02 was only ~25% (6:52). Rolling cache solves that. ¹

Compile job	Before 2	After	Improvement
Linux release	7:54	0:28	94%
Benchmark	2:33	0:17	89%
Unit tests	2:06	0:14	89%
Linux ASAN	1:50	0:27	75%
macOS	4:07	1:30	64%
Alpine ASAN	2:37	0:57	64%
Linux x32	2:10	0:57	56%

Cache hit rate: ~99%.

9de2a2e

Skip unused setup in the ordinary Linux ASAN job

Setup	Before	After	Improvement
Service containers	1:24	0:13	85%
MSSQL setup	0:14	Skipped	100%
Apt dependencies	0:54	0:42	22%
Total targeted setup	2:32	0:55	64%

Saves 1:37 per ASAN run. Depending on download speeds shaves off 1–3 min.

Footnotes

1. each new master commit rolls the cache forward. ↩

2. when cache not fresh. ↩

[Girgias]

You could just use the CI labels.

[NickSdot]

Seems to require explicit permissions. GUI doesn't allow and gh refuses.