ci: stabilize Windows test-cost ratchet

.github/workflows/ci.yml

@@ -230,7 +230,7 @@ jobs:
 
       - name: Windows test-cost ratchet
         if: needs.changes.result == 'success' && matrix.os == 'windows-latest' && (contains(github.event.pull_request.labels.*.name, 'allow-test-cost-growth') || contains(github.event.pull_request.labels.*.name, 'run-test-cost') || contains(github.event.pull_request.labels.*.name, 'test-cost') || needs.changes.outputs.test_cost == 'true')
-        timeout-minutes: 20
+        timeout-minutes: 30
         shell: pwsh
         env:
           # A labeled PR may authorize a ratchet update, but the orchestrator

internal/core/runtime/parallel_race_late_arm_race_test.go

@@ -169,6 +169,12 @@ func TestTryOpenParallelGroup_ContextDoneLateArmStillTerminalized(t *testing.T)
 		t.Fatal("tryOpenParallelGroup did not return after release")
 	}
 
+	deadline := time.Now().Add(5 * time.Second)
+	for time.Now().Before(deadline) &&
+		(fastStream.cancelCount.Load() == 0 && fastStream.closeCount.Load() == 0 ||
+			lateStream.cancelCount.Load() == 0 && lateStream.closeCount.Load() == 0) {
+		time.Sleep(10 * time.Millisecond)
+	}
 	if fastStream.cancelCount.Load() == 0 && fastStream.closeCount.Load() == 0 {
 		t.Errorf("expected fast arm to be terminalized (cancel or close)")
 	}

internal/qa/ci_iteration_speed_contract_test.go

@@ -413,8 +413,8 @@ func TestQAFastPreflight_TestCostRatchetContracts(t *testing.T) {
 		t.Fatal("CI must place the Windows test-cost ratchet before building the release binary")
 	}
 	ratchetBlock := ci[ratchet:buildBinary]
-	if !strings.Contains(ratchetBlock, "timeout-minutes: 20") {
-		t.Fatal("Windows test-cost ratchet step must declare timeout-minutes: 20")
+	if !strings.Contains(ratchetBlock, "timeout-minutes: 30") {
+		t.Fatal("Windows test-cost ratchet step must declare timeout-minutes: 30")
 	}
 	if !strings.Contains(ratchetBlock, "& ./scripts/test-cost-ratchet.ps1") {
 		t.Fatal("Windows test-cost ratchet step must invoke & ./scripts/test-cost-ratchet.ps1 directly")

scripts/test-cost-budget.json

@@ -27,7 +27,7 @@
     },
     "quality-checks": {
       "cpu": { "ratio": 1.30, "delta_seconds": 5 },
-      "processes": { "ratio": 1.15, "delta": 6 },
+      "processes": { "ratio": 1.15, "delta": 8 },
       "io_operations": { "ratio": 1.40, "delta": 7500 },
       "wall": { "ratio": 1.50, "delta_seconds": 10 }
     },

scripts/test-cost-ratchet.ps1

@@ -409,6 +409,36 @@ function Apply-AnchorCompatibilityPatch {
     Test-CleanCheckout $AnchorRoot
 }
 
+function Apply-CurrentAnchorLoadCompatibilityPatch {
+    param(
+        [Parameter(Mandatory = $true)][string]$RepositoryRoot,
+        [Parameter(Mandatory = $true)][string]$AnchorRoot,
+        [Parameter(Mandatory = $true)][string]$AnchorCommit
+    )
+
+    $currentAnchor = "6dbb831885341516117034923f0c3203373aded0"
+    if ($AnchorCommit -ne $currentAnchor) {
+        return
+    }
+
+    # The pinned anchor's late-arm assertion must wait for asynchronous
+    # terminalization when the full suite saturates a Windows runner.
+    $relativePath = "internal/core/runtime/parallel_race_late_arm_race_test.go"
+    Copy-Item -LiteralPath (Join-Path $RepositoryRoot $relativePath) -Destination (Join-Path $AnchorRoot $relativePath) -Force
+    $absolutePath = Join-Path $AnchorRoot $relativePath
+    $content = [IO.File]::ReadAllText($absolutePath)
+    [IO.File]::WriteAllText($absolutePath, $content.Replace("`r`n", "`n"), [Text.UTF8Encoding]::new($false))
+    Invoke-GitChecked @("-C", $AnchorRoot, "add", "--", $relativePath)
+    Invoke-GitChecked @(
+        "-C", $AnchorRoot,
+        "-c", "user.name=Go-LIP test-cost ratchet",
+        "-c", "user.email=test-cost-ratchet@invalid.local",
+        "-c", "commit.gpgsign=false",
+        "commit", "-m", "test: stabilize pinned anchor late-arm assertion"
+    )
+    Test-CleanCheckout $AnchorRoot
+}
+
 function Build-TestCostBinary {
     param(
         [Parameter(Mandatory = $true)][string]$Label,
@@ -588,6 +618,7 @@ try {
     )
     $anchorCreated = $true
     Apply-AnchorCompatibilityPatch $RepositoryRoot $anchorRoot $AnchorCommit $anchorTempRoot
+    Apply-CurrentAnchorLoadCompatibilityPatch $RepositoryRoot $anchorRoot $AnchorCommit
 
     # The committed anchor predates the ratchet tool itself. Build the neutral
     # measurement wrapper once from head, then point it at each source tree.