mesh-build-go: keep a check ask's cache layer beside its workspace, for the build cache alone

Review of dda14e0e: the layer lay in the workspace, which every step binds read-write, and covered the module cache too. It is now the workspace's Workspaces.CacheLayer, removed by Release and Sweep, and holds only the build cache; the module cache keeps its throwaway layer. Pins mesh-build-go and mesh-build-node to mesh-sdk 979f2cd, the group's head (issue 1921).
mesh-build-go: give each ask a cache layer in its workspace, so what its digest and vet compile its tests find compiled
2026-10-29 01:05:18 +01:00 · 2026-10-29 00:54:45 +01:00 · 2026-10-29 00:54:13 +01:00 · 2026-10-29 00:54:13 +01:00 · 2026-10-29 00:10:42 +01:00
6 changed files with 25 additions and 17 deletions
@@ -43,16 +43,15 @@ func (m *Module) isolation(workspace string, write bool) buildstep.Isolation {
 		Env:         append([]string{"PATH=" + path, "LC_ALL=C"}, m.threadEnv()...),
 	}
 	if !write {
-		// What one command of the ask compiles is kept for its later commands (the vet, the unit tests, the integration
-		// level's compile), in the workspace and gone with it (issue 1921, try speed S2).
-		iso.CacheLayer = filepath.Join(iso.Workspace, cacheLayerDir)
+		// What one command of the ask compiles into the build cache is kept for its later commands (the digests, the unit
+		// tests, the integration level's compile), beside the workspace, out of every step's reach, and gone with it
+		// (issue 1921, try speed S2); the module cache keeps its throwaway layer.
+		iso.CacheLayer = m.spaces().CacheLayer(workspace)
+		iso.LayerCaches = []string{filepath.Join(m.Cache, "gobuild")}
 	}
 	return iso
 }

-// cacheLayerDir is the directory in a workspace's root where an ask keeps what its commands wrote into the caches.
-const cacheLayerDir = "cachelayer"
-
 // stepRunner is the runner of a run step of the workspace: buildstep.Isolated over m.Run, so every command it runs is
 // shut off; write is true for a trunk build and for a check's go vet, compile steps that run nothing of the change (ADR 0541 §2). Inside is the
 // integration level's own process, already running shut off (level.go): it runs its commands as they are.
@@ -111,9 +111,12 @@ func checkShutOff(t *testing.T, m *Module, s shutOff, write bool) {
 			t.Errorf("a trunk build's %s does not write the shared cache %s (bound %v, layered %v)", s.command, c, bound, layered)
 		case !write && (bound || !layered):
 			t.Errorf("%s may write the shared cache %s (bound %v, layered %v): only a trunk build does", s.command, c, bound, layered)
-		case !write && !strings.HasPrefix(s.uppers[c], filepath.Join(m.Work, "ws1", "cachelayer")+"/"):
-			// 1921/S2: what one command of the ask compiles is kept for its later commands, in the workspace
-			t.Errorf("%s writes the cache %s into %q, not the ask's cache layer in its workspace", s.command, c, s.uppers[c])
+		case !write && c == filepath.Join(m.Cache, "gobuild") && !strings.HasPrefix(s.uppers[c], filepath.Join(m.Work, "ws1.cachelayer")+"/"):
+			// 1921/S2: what one command of the ask compiles is kept for its later commands, beside the workspace
+			t.Errorf("%s writes the build cache %s into %q, not the ask's cache layer beside its workspace", s.command, c, s.uppers[c])
+		case !write && c != filepath.Join(m.Cache, "gobuild") && s.uppers[c] != "":
+			// the module cache keeps its throwaway layer
+			t.Errorf("%s keeps what it writes into the module cache %s (in %q)", s.command, c, s.uppers[c])
 		}
 	}
 	if want := filepath.Join(m.Work, "ws1"); !slices.Contains(s.binds, want) {
@@ -3,7 +3,7 @@ module meshbuildgo
 go 1.26.0

 require (
-	git.novox.be/novox/mesh-sdk/go v0.1.14-0.20261028235126-2a8670189188
+	git.novox.be/novox/mesh-sdk/go v0.1.14-0.20261029000420-979f2cd71819
 	github.com/distribution/distribution/v3 v3.1.2
 	github.com/nats-io/nats-server/v2 v2.11.17
 	github.com/nats-io/nats.go v1.54.0
@@ -1,7 +1,9 @@
-git.novox.be/novox/mesh-sdk/go v0.1.14-0.20261028190821-9e5666b4d6f5 h1:L7EJbCPZfJRCYHyco5Ck3ui+pWc//sp+h5nnPqSarng=
-git.novox.be/novox/mesh-sdk/go v0.1.14-0.20261028190821-9e5666b4d6f5/go.mod h1:ouERNpZizzwZ0HLEtAypsY9FR20FyUgUYRni6J7kVCY=
-git.novox.be/novox/mesh-sdk/go v0.1.14-0.20261028235126-2a8670189188 h1:0ZJZmp4wqiJlBlVHAdGonVIRaLf0Z79Ql4DFR2k8E8c=
-git.novox.be/novox/mesh-sdk/go v0.1.14-0.20261028235126-2a8670189188/go.mod h1:ouERNpZizzwZ0HLEtAypsY9FR20FyUgUYRni6J7kVCY=
+git.novox.be/novox/mesh-sdk/go v0.1.14-0.20261028230718-261f41aec1ae h1:bwcj9NnfGk/DP0sbTRInPAA4aMUnvr8+CmQLhnDvV9w=
+git.novox.be/novox/mesh-sdk/go v0.1.14-0.20261028230718-261f41aec1ae/go.mod h1:ouERNpZizzwZ0HLEtAypsY9FR20FyUgUYRni6J7kVCY=
+git.novox.be/novox/mesh-sdk/go v0.1.14-0.20261028235320-62a50ebcf822 h1:od9tMSw9yHRLe4c03/u9EVr7TpXZ+pEJa2XY5evx6Ho=
+git.novox.be/novox/mesh-sdk/go v0.1.14-0.20261028235320-62a50ebcf822/go.mod h1:ouERNpZizzwZ0HLEtAypsY9FR20FyUgUYRni6J7kVCY=
+git.novox.be/novox/mesh-sdk/go v0.1.14-0.20261029000420-979f2cd71819 h1:ypKERyJAbbsydMKLlPmWKU++wU2YCPLzGC0nzdw6QvQ=
+git.novox.be/novox/mesh-sdk/go v0.1.14-0.20261029000420-979f2cd71819/go.mod h1:ouERNpZizzwZ0HLEtAypsY9FR20FyUgUYRni6J7kVCY=
 github.com/alicebob/miniredis/v2 v2.35.0 h1:QwLphYqCEAo1eu1TqPRN2jgVMPBweeQcR21jeqDCONI=
 github.com/alicebob/miniredis/v2 v2.35.0/go.mod h1:TcL7YfarKPGDAthEtl5NBeHZfeUQj6OXMm/+iu5cLMM=
 github.com/antithesishq/antithesis-sdk-go v0.7.0-default-no-op h1:Z/MZK75wC/NSrkgqeNIa7jexam9uWzhLmFTSCPI/kn0=
@@ -3,7 +3,7 @@ module meshbuildnode
 go 1.26.0

 require (
-	git.novox.be/novox/mesh-sdk/go v0.1.14-0.20261028190821-9e5666b4d6f5
+	git.novox.be/novox/mesh-sdk/go v0.1.14-0.20261029000420-979f2cd71819
 	github.com/distribution/distribution/v3 v3.1.2
 	github.com/nats-io/nats.go v1.54.0
 )
@@ -1,5 +1,9 @@
-git.novox.be/novox/mesh-sdk/go v0.1.14-0.20261028190821-9e5666b4d6f5 h1:L7EJbCPZfJRCYHyco5Ck3ui+pWc//sp+h5nnPqSarng=
-git.novox.be/novox/mesh-sdk/go v0.1.14-0.20261028190821-9e5666b4d6f5/go.mod h1:ouERNpZizzwZ0HLEtAypsY9FR20FyUgUYRni6J7kVCY=
+git.novox.be/novox/mesh-sdk/go v0.1.14-0.20261028230718-261f41aec1ae h1:bwcj9NnfGk/DP0sbTRInPAA4aMUnvr8+CmQLhnDvV9w=
+git.novox.be/novox/mesh-sdk/go v0.1.14-0.20261028230718-261f41aec1ae/go.mod h1:ouERNpZizzwZ0HLEtAypsY9FR20FyUgUYRni6J7kVCY=
+git.novox.be/novox/mesh-sdk/go v0.1.14-0.20261028235320-62a50ebcf822 h1:od9tMSw9yHRLe4c03/u9EVr7TpXZ+pEJa2XY5evx6Ho=
+git.novox.be/novox/mesh-sdk/go v0.1.14-0.20261028235320-62a50ebcf822/go.mod h1:ouERNpZizzwZ0HLEtAypsY9FR20FyUgUYRni6J7kVCY=
+git.novox.be/novox/mesh-sdk/go v0.1.14-0.20261029000420-979f2cd71819 h1:ypKERyJAbbsydMKLlPmWKU++wU2YCPLzGC0nzdw6QvQ=
+git.novox.be/novox/mesh-sdk/go v0.1.14-0.20261029000420-979f2cd71819/go.mod h1:ouERNpZizzwZ0HLEtAypsY9FR20FyUgUYRni6J7kVCY=
 github.com/alicebob/miniredis/v2 v2.35.0 h1:QwLphYqCEAo1eu1TqPRN2jgVMPBweeQcR21jeqDCONI=
 github.com/alicebob/miniredis/v2 v2.35.0/go.mod h1:TcL7YfarKPGDAthEtl5NBeHZfeUQj6OXMm/+iu5cLMM=
 github.com/antithesishq/antithesis-sdk-go v0.7.0-default-no-op h1:Z/MZK75wC/NSrkgqeNIa7jexam9uWzhLmFTSCPI/kn0=
Author	SHA1	Message	Date
jschoubben	48a68b4b9e	mesh-build-go: keep a check ask's cache layer beside its workspace, for the build cache alone Review of `dda14e0e`: the layer lay in the workspace, which every step binds read-write, and covered the module cache too. It is now the workspace's Workspaces.CacheLayer, removed by Release and Sweep, and holds only the build cache; the module cache keeps its throwaway layer. Pins mesh-build-go and mesh-build-node to mesh-sdk 979f2cd, the group's head (issue 1921).	2026-10-29 01:05:18 +01:00
jschoubben	dda14e0e22	mesh-build-go: give each ask a cache layer in its workspace, so what its digest and vet compile its tests find compiled Pins mesh-build-go and mesh-build-node to mesh-sdk 62a50eb, the group's head, whose Isolation.CacheLayer keeps what one command of an ask writes into the caches for the ask's later commands, the shared cache unchanged (mesh-build-node sets no layer and behaves as before). A trunk build and the lint's vet still write the shared cache directly. Ported from feat/try-speed S2 (issue 1921; ADR 0541 §2).	2026-10-29 00:54:45 +01:00
jschoubben	6fa42dd69f	mesh-build-go: start the integration level's store and bus beside its compile, and compile the go.mod directories side by side The setup started the store, then the bus, then compiled each directory one after another: 132 s of setup in the L3 group check. Now the three start together and the directories compile up to the bound at once; the compile runs no test binary (-exec true), so it needs neither server and is given nothing a test reads. Ported from feat/try-speed S5 (issue 1921; ADR 0541 §1).	2026-10-29 00:54:13 +01:00
jschoubben	37fb9f01aa	mesh-build-go: let a check's go vet warm the shared Go build cache with cgo off, and say each linted directory as it ends A check's lint recompiled every package from a cold layer on each ask (g14 linted mesh-catalog's 8 directories in 141 s where ace, warm, took 17 s), and said nothing until it ended. ADR 0541 §2 and ADR 0542 §1 decided this; the built speed-up on feat/try-speed (S11) was parked. Ported here alone: CGO_ENABLED=0 in every check command's go environment, vet runs with the shared caches writable, and the lint says a phase per finished directory (issue 1921).	2026-10-29 00:54:13 +01:00
jschoubben	5dccf3820b	Pin mesh-build-go and mesh-build-node to mesh-sdk 261f41a, so a merge-only check ask answers the merge and runs no tests The checker now asks the remaining group members' merges alone after a failure; a build module before it would run both levels per member (issue 1921's kind; no open issue covers it).	2026-10-29 00:10:42 +01:00