ci(seed): keep the trusted seed on the Mac before the R2 upload

.github/workflows/seed-derived-data.yml

@@ -445,6 +445,20 @@ jobs:
         id: bound
         run: python3 scripts/ci/seed_derived_data.py prune "$CMUX_COMPILE_ADMISSION_DERIVED_DATA"
 
+      # Before the R2 upload, and before the product steps below rewrite
+      # Build/Products: the copy is the seed exactly as "Save seed" uploads it
+      # (keep only clones the tree). An APFS clone, so seconds. The LAN seed
+      # archive reads kept seeds from this Mac within a minute, so keeping
+      # first hands them to the owned minis about 160 s sooner, the length of
+      # the upload (cmuxterm-hq#658).
+      - name: Keep the seed on this Mac
+        if: steps.bound.outputs.save == 'true' && env.CMUX_SEED_LOCAL_CACHE != ''
+        continue-on-error: true
+        env:
+          SEED_KEY: ${{ steps.key.outputs.scoped }}${{ github.sha }}
+          SEED_PREFIX: ${{ steps.key.outputs.prefix }}
+        run: python3 scripts/ci/seed_derived_data.py keep "$CMUX_COMPILE_ADMISSION_DERIVED_DATA" "$SEED_KEY" "$SEED_PREFIX"
+
       - name: Save seed
         if: steps.bound.outputs.save == 'true'
         uses: ./.github/actions/cache-save
@@ -458,16 +472,6 @@ jobs:
           path: ${{ env.CMUX_COMPILE_ADMISSION_DERIVED_DATA }}
           key: ${{ steps.key.outputs.scoped }}${{ github.sha }}
 
-      # Before the product steps below rewrite Build/Products: the copy must
-      # be the seed exactly as saved. An APFS clone, so seconds.
-      - name: Keep the seed on this Mac
-        if: steps.bound.outputs.save == 'true' && env.CMUX_SEED_LOCAL_CACHE != ''
-        continue-on-error: true
-        env:
-          SEED_KEY: ${{ steps.key.outputs.scoped }}${{ github.sha }}
-          SEED_PREFIX: ${{ steps.key.outputs.prefix }}
-        run: python3 scripts/ci/seed_derived_data.py keep "$CMUX_COMPILE_ADMISSION_DERIVED_DATA" "$SEED_KEY" "$SEED_PREFIX"
-
       # Publish the product exactly as ci-macos.yml compile admission does
       # (tests/test_seed_derived_data.py pins the copy). Staging and relocation
       # rewrite Build/Products, so these follow "Save seed". Only a main push

tests/test_seed_derived_data.py

@@ -229,16 +229,18 @@ def test_a_seed_job_records_its_prefix_so_the_mac_prefetches_between_jobs(self):
             self.assertEqual(seed.main(["seed", "keep", str(self.derived), "k2", "../evil-"]), 0)
         self.assertFalse((self.root / "cmux-ci-2" / seed.SEED_SOURCE).exists())
 
-    def test_the_trusted_seed_job_keeps_its_seeds_between_save_and_the_product_steps(self):
+    def test_the_trusted_seed_job_keeps_its_seeds_before_save_and_the_product_steps(self):
+        """Keep clones the seed before the R2 upload, so the LAN archive need not wait for it."""
         seeder = steps("seed-derived-data.yml", "seed")
         choose_at, choose = named(seeder, "Keep seeds on a trusted Mac")
         adopt_at, _ = named(seeder, "Adopt the newest seed")
         save_at, _ = named(seeder, "Save seed")
         keep_at, keep = named(seeder, "Keep the seed on this Mac")
         stage_at, _ = named(seeder, "Stage compiled package frameworks")
         self.assertLess(choose_at, adopt_at)
-        self.assertLess(save_at, keep_at)
-        self.assertLess(keep_at, stage_at)
+        self.assertLess(adopt_at, keep_at)
+        self.assertLess(keep_at, save_at)  # the LAN archive gets the seed without waiting on R2
+        self.assertLess(save_at, stage_at)
         self.assertIn("matrix.pool == vars.CI_SEED_TRUSTED_POOL", choose["if"])
         # only runners that run nothing else as this user: a kept seed becomes the next R2 seed
         self.assertIn("vars.CI_SEED_KEEP_LOCAL_RUNNERS", choose["if"])