test(vulkan): explain the dmabuf alloc budget and report the sync path

commit: d55622625bd5bd0b280f43c5a5362f3d2735d734
author: brice · 9d ago · 2026-10-13 18:33 UTC
parent: 0f2ac29
signature: GPG VerifiedCD88F9E564E0102646FB6077A1A07C7C7C3E349D · arch-gpg Verified for the committer email

1 file · +6 -4

M internal/adapters/vulkan/scene_perf_test.go +6 -4


@@ -42,7 +42,7 @@ func TestRenderSteadyStateAllocations(t *testing.T) {
42	42		}
43	43		frame()
44	44		if allocs := testing.AllocsPerRun(20, frame); allocs > 3 {
45		-	t.Errorf("small steady-state Render: %.1f allocs/frame, want <=3", allocs)
	45	+	t.Errorf("small steady-state Render: %.1f allocs/frame, want <=3 (syncFD path: %v)", allocs, r.syncFD)
46	46		} else {
47	47		t.Logf("small steady-state Render: %.1f allocs/frame", allocs)
48	48		}

@@ -138,8 +138,10 @@ func TestRenderSteadyStateAllocations(t *testing.T) {
138	138		}
139	139
140	140		// A steady frame that draws a client dmabuf also records the ownership
141		-	// barriers (acquire and release) of its image: no allocation per frame beyond
142		-	// the SHM scene's. Skipped without a GPU or /dev/udmabuf.
	141	+	// barriers (acquire and release) of its image, which allocate nothing. The
	142	+	// frame still allocates more than the SHM scene: importing the client's
	143	+	// read fence and its retire closure (about 4 per frame). Skipped without a
	144	+	// GPU or /dev/udmabuf.
143	145		func TestRenderSteadyStateDMABufAllocations(t *testing.T) {
144	146		r, err := New(80, 32)
145	147		if err != nil {

@@ -181,7 +183,7 @@ func TestRenderSteadyStateDMABufAllocations(t *testing.T) {
181	183		allocs := testing.AllocsPerRun(20, moved)
182	184		t.Logf("dmabuf Render: %.1f allocs/frame", allocs)
183	185		if allocs > 7 {
184		-	t.Errorf("dmabuf steady-state Render: %.1f allocs/frame, want <=7", allocs)
	186	+	t.Errorf("dmabuf steady-state Render: %.1f allocs/frame, want <=7 (syncFD path: %v; a driver without sync-file export takes another path)", allocs, r.syncFD)
185	187		}
186	188		}
187	189

 			}
 			frame()
 			if allocs := testing.AllocsPerRun(20, frame); allocs > 3 {
-				t.Errorf("small steady-state Render: %.1f allocs/frame, want <=3", allocs)
+				t.Errorf("small steady-state Render: %.1f allocs/frame, want <=3 (syncFD path: %v)", allocs, r.syncFD)
 			} else {
 				t.Logf("small steady-state Render: %.1f allocs/frame", allocs)
 			}
 }
 // A steady frame that draws a client dmabuf also records the ownership
-// barriers (acquire and release) of its image: no allocation per frame beyond
+// barriers (acquire and release) of its image, which allocate nothing. The
-// the SHM scene's. Skipped without a GPU or /dev/udmabuf.
+// frame still allocates more than the SHM scene: importing the client's
+// read fence and its retire closure (about 4 per frame). Skipped without a
+// GPU or /dev/udmabuf.
 func TestRenderSteadyStateDMABufAllocations(t *testing.T) {
 	r, err := New(80, 32)
 	if err != nil {
 	allocs := testing.AllocsPerRun(20, moved)
 	t.Logf("dmabuf Render: %.1f allocs/frame", allocs)
 	if allocs > 7 {
-		t.Errorf("dmabuf steady-state Render: %.1f allocs/frame, want <=7", allocs)
+		t.Errorf("dmabuf steady-state Render: %.1f allocs/frame, want <=7 (syncFD path: %v; a driver without sync-file export takes another path)", allocs, r.syncFD)
 	}
 }