Given tests: order arrivals by limiter state instead of sleeps (limiter, spread, cancel-while-queued)

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>

docs/plans/v1.1/_files/internal/proxy/cancel_test.go

@@ -84,7 +84,7 @@ hosts = ["alpha"]
 default_model = "shared"
 `, alpha)
 	go func() { drain(r.post("/r/v1/chat/completions", conversation(1, 1))) }() // holds the one slot
-	time.Sleep(100 * time.Millisecond)
+	waitUntil(t, func() bool { return r.lim.InFlight("alpha", "shared") == 1 })
 	ctx, cancel := context.WithTimeout(context.Background(), 150*time.Millisecond)
 	defer cancel()
 	req, _ := http.NewRequestWithContext(ctx, http.MethodPost, r.front.URL+"/r/v1/chat/completions", strings.NewReader(conversation(2, 1)))

docs/plans/v1/_files/internal/limiter/limiter_test.go

@@ -39,10 +39,7 @@ func TestParallelAndQueue(t *testing.T) {
 		}
 		got3 <- err
 	}()
-	time.Sleep(20 * time.Millisecond)
+	waitUntil(t, func() bool { return l.Queued("alpha", "m") == 1 })
-	if l.Queued("alpha", "m") != 1 {
-		t.Errorf("queued = %d, want 1", l.Queued("alpha", "m"))
-	}
 	// Fourth finds the queue full and is refused at once.
 	start := time.Now()
 	_, _, err = l.Acquire(ctx, "alpha", "m")
@@ -52,7 +49,7 @@ func TestParallelAndQueue(t *testing.T) {
 	if time.Since(start) > 50*time.Millisecond {
 		t.Errorf("a full queue must refuse immediately, took %v", time.Since(start))
 	}
-	time.Sleep(30 * time.Millisecond)
+	time.Sleep(50 * time.Millisecond) // a lower bound on the third's wait, checked above as >= 40 ms
 	rel1()                            // frees a slot: the queued third proceeds
 	select {
 	case err := <-got3:
@@ -95,7 +92,7 @@ func TestCancelWhileQueuedLeaksNothing(t *testing.T) {
 	ctx, cancel := context.WithCancel(context.Background())
 	done := make(chan error, 1)
 	go func() { _, _, err := l.Acquire(ctx, "h", "m"); done <- err }()
-	time.Sleep(20 * time.Millisecond)
+	waitUntil(t, func() bool { return l.Queued("h", "m") == 1 })
 	cancel()
 	select {
 	case err := <-done:
@@ -139,7 +136,7 @@ func TestQueueIsFIFO(t *testing.T) {
 			time.Sleep(5 * time.Millisecond)
 			r()
 		}(i)
-		time.Sleep(15 * time.Millisecond) // stagger arrivals so the order is defined
+		waitUntil(t, func() bool { return l.Queued("h", "m") == i }) // arrivals in order, by observation
 	}
 	rel()
 	wg.Wait()
@@ -176,3 +173,16 @@ func TestFreeSlotsSumsModels(t *testing.T) {
 		t.Errorf("unknown host has no slots")
 	}
 }
+
+// waitUntil polls cond every millisecond for up to two seconds and fails the test if it never holds.
+func waitUntil(t *testing.T, cond func() bool) {
+	t.Helper()
+	deadline := time.Now().Add(2 * time.Second)
+	for time.Now().Before(deadline) {
+		if cond() {
+			return
+		}
+		time.Sleep(time.Millisecond)
+	}
+	t.Fatal("condition not reached within two seconds")
+}

docs/plans/v1/_files/internal/proxy/proxy_test.go

@@ -70,9 +70,9 @@ func TestDifferentConversationsSpreadByFreeSlots(t *testing.T) {
 	for i := 1; i <= 2; i++ {
 		wg.Add(1)
 		go func(i int) { defer wg.Done(); drain(r.post("/r/v1/chat/completions", conversation(i, 1))) }(i)
-		time.Sleep(50 * time.Millisecond) // arrive one after the other so both pick beta (10 > 2)
+		// arrive one after the other so both pick beta (10 > 2): wait until beta holds i slots
+		waitUntil(t, func() bool { return r.lim.InFlight("beta", "shared") == i })
 	}
-	time.Sleep(50 * time.Millisecond)
 	// …so a third conversation starting now is sent to alpha (beta has 0 free slots, alpha 2).
 	resp := r.post("/r/v1/chat/completions", conversation(3, 1))
 	drain(resp)

docs/plans/v2.1/README.md

@@ -12,8 +12,10 @@
 - **02-props-loaded-only** (to be written after v2 merges) — the poller asks `/props?model=X`
   only for models `/v1/models` lists as loaded, because llama-server's router autoloads a model
   named in that query (`models_autoload`). See the v2 README's note of 2026-09-25.
-- **03-timing-margins** (to be written) — the remaining sleep-ordered assertions in v1 and v2
+- ~~03-timing-margins~~ — done by the owner directly (test-only work, no implementer task): the
-  given tests move to state-based waits, as `TestQueueFullIs503` and `TestParallelAndQueue` did.
+  remaining ordering sleeps in `limiter_test.go`, `proxy_test.go` and `cancel_test.go` now wait on
+  limiter state (`Queued`/`InFlight`); the one sleep left is a deliberate lower bound. Five clean
+  `-race` runs of both packages except the 499 defect task 01 fixes.
 
 **How this plan was made:** acceptance tests first; no reference implementation. The given test
 for task 01 was run against the v2 tree (fails six of six) and against a throwaway fix that

internal/limiter/limiter_test.go

@@ -39,10 +39,7 @@ func TestParallelAndQueue(t *testing.T) {
 		}
 		got3 <- err
 	}()
-	time.Sleep(20 * time.Millisecond)
+	waitUntil(t, func() bool { return l.Queued("alpha", "m") == 1 })
-	if l.Queued("alpha", "m") != 1 {
-		t.Errorf("queued = %d, want 1", l.Queued("alpha", "m"))
-	}
 	// Fourth finds the queue full and is refused at once.
 	start := time.Now()
 	_, _, err = l.Acquire(ctx, "alpha", "m")
@@ -52,7 +49,7 @@ func TestParallelAndQueue(t *testing.T) {
 	if time.Since(start) > 50*time.Millisecond {
 		t.Errorf("a full queue must refuse immediately, took %v", time.Since(start))
 	}
-	time.Sleep(30 * time.Millisecond)
+	time.Sleep(50 * time.Millisecond) // a lower bound on the third's wait, checked above as >= 40 ms
 	rel1()                            // frees a slot: the queued third proceeds
 	select {
 	case err := <-got3:
@@ -95,7 +92,7 @@ func TestCancelWhileQueuedLeaksNothing(t *testing.T) {
 	ctx, cancel := context.WithCancel(context.Background())
 	done := make(chan error, 1)
 	go func() { _, _, err := l.Acquire(ctx, "h", "m"); done <- err }()
-	time.Sleep(20 * time.Millisecond)
+	waitUntil(t, func() bool { return l.Queued("h", "m") == 1 })
 	cancel()
 	select {
 	case err := <-done:
@@ -139,7 +136,7 @@ func TestQueueIsFIFO(t *testing.T) {
 			time.Sleep(5 * time.Millisecond)
 			r()
 		}(i)
-		time.Sleep(15 * time.Millisecond) // stagger arrivals so the order is defined
+		waitUntil(t, func() bool { return l.Queued("h", "m") == i }) // arrivals in order, by observation
 	}
 	rel()
 	wg.Wait()
@@ -176,3 +173,16 @@ func TestFreeSlotsSumsModels(t *testing.T) {
 		t.Errorf("unknown host has no slots")
 	}
 }
+
+// waitUntil polls cond every millisecond for up to two seconds and fails the test if it never holds.
+func waitUntil(t *testing.T, cond func() bool) {
+	t.Helper()
+	deadline := time.Now().Add(2 * time.Second)
+	for time.Now().Before(deadline) {
+		if cond() {
+			return
+		}
+		time.Sleep(time.Millisecond)
+	}
+	t.Fatal("condition not reached within two seconds")
+}

internal/proxy/cancel_test.go

@@ -84,7 +84,7 @@ hosts = ["alpha"]
 default_model = "shared"
 `, alpha)
 	go func() { drain(r.post("/r/v1/chat/completions", conversation(1, 1))) }() // holds the one slot
-	time.Sleep(100 * time.Millisecond)
+	waitUntil(t, func() bool { return r.lim.InFlight("alpha", "shared") == 1 })
 	ctx, cancel := context.WithTimeout(context.Background(), 150*time.Millisecond)
 	defer cancel()
 	req, _ := http.NewRequestWithContext(ctx, http.MethodPost, r.front.URL+"/r/v1/chat/completions", strings.NewReader(conversation(2, 1)))

internal/proxy/proxy_test.go

@@ -70,9 +70,9 @@ func TestDifferentConversationsSpreadByFreeSlots(t *testing.T) {
 	for i := 1; i <= 2; i++ {
 		wg.Add(1)
 		go func(i int) { defer wg.Done(); drain(r.post("/r/v1/chat/completions", conversation(i, 1))) }(i)
-		time.Sleep(50 * time.Millisecond) // arrive one after the other so both pick beta (10 > 2)
+		// arrive one after the other so both pick beta (10 > 2): wait until beta holds i slots
+		waitUntil(t, func() bool { return r.lim.InFlight("beta", "shared") == i })
 	}
-	time.Sleep(50 * time.Millisecond)
 	// …so a third conversation starting now is sent to alpha (beta has 0 free slots, alpha 2).
 	resp := r.post("/r/v1/chat/completions", conversation(3, 1))
 	drain(resp)