Author	SHA1	Message	Date
pat-s	e23bd3e539	perf: seed pure-R binaries into a new slot, interleave shards, and stop builds before the timeout (#242) ... Speeds up the full rebuild for a new slot, e.g. the upcoming Alpine version. ## Changes - **Seed pure-R binaries** (`local/seed-pure-r.R`, `local/seed-helpers.R`), opt-in via the new `SEED_FROM` variable on `build-all-versions-install-deps`. About 74% of the ~84k candidate versions have no compiled code and cost ~20s each to build; their R objects are identical across slots. Before the build list is computed, each donor candidate is downloaded and verified, then copied server-side: - donor must be the same OS family and arch; - DESCRIPTION has `Built` (not a CRAN source fallback) with an empty platform and no `libs/`; - built by the target's primary R minor; - bincraft's `tarball_abi_verdict()` calls it portable across every installed minor (unknown means no seed). Each copy gets the `single_builds` and `abi_flat_safety` rows an upload writes, so build-all skips it and the per-minor indexes keep it. Re-runs skip existing objects and rewrite rows idempotently. - **Interleaved shards** in `local/build-all.R` via `shard_slice()`; contiguous alphabetical quarters ranged from 0.1h to 28h. - **Shared build deadline**: `build-all-versions` sets `BUILD_DEADLINE` from `BUILD_BUDGET_HOURS` (44h, repo timeout 50h); `build-all.R` and `build-newer-r.R` stop cleanly when it passes, so archiving still runs. - `codename_platform()` replaces the hard-coded codename-to-platform list. ## Testing - New unit tests for the seed verdict, candidate filter, platform names and deadline; all `local/tests` pass. - Verdicts checked on real amd64/alpine324 tarballs: R6 2.6.1/2.5.1 and jsonstat seeded, cli refused as compiled. - `crow lint .crow/` passes. - The seed has not run against B2/Postgres yet; the first bootstrap run is its end-to-end test. ## Usage Trigger `build-all-versions` with `target_arch`, `OS`, `OS_VERSION` and `SEED_FROM="alpine324 alpine323"`. The new Alpine version still needs adding to the `OS_VERSION` options once its image exists. Reviewed-on: #242	2026-10-24 02:04:06 +00:00