Merge pull request #343 from bnema/perf/startup-first-presentation

perf(startup): trace first GTK presentation

commit: 41933ea68d5c3abc53fc57b247cf575ea912ce71
author: bnema · 3mo ago · 2026-07-14 10:05 UTC
committer: GitHub · 3mo ago · 2026-07-14 10:05 UTC
merge of: aaec84c + 8b5f874 · diff against the first parent
signature: GPG UnverifiedB5690EEEBB952194 The key is unknown

19 files · +1208 -184

M cmd/dumber/main.go +6 -1


@@ -141,6 +141,11 @@ func configureBrowserLaunchRelay(cfg *config.Config) {
141	141		}
142	142
143	143		func main() {
	144	+	// This is intentionally before subprocess detection: each process records
	145	+	// its own first observable main event before CEF can take over execution.
	146	+	logging.InitStartupTrace("")
	147	+	logging.Trace().Mark("process_entry")
	148	+
144	149		// CEF subprocess handling: when CEF re-launches this binary with
145	150		// --type=renderer/gpu/etc, we must call ExecuteProcess before anything
146	151		// else (Cobra, config, arg stripping). We only treat a leading Chromium

@@ -218,6 +223,7 @@ func runGUI(cfg *config.Config) int {
218	223		cfg = initConfig()
219	224		configureBrowserLaunchRelay(cfg)
220	225		}
	226	+	logging.Trace().Mark("config_complete")
221	227		timer.Mark("config")
222	228
223	229		ctx := initStartupContextWithTrace(cfg)

@@ -414,7 +420,6 @@ func resolveCurrentExecutable(executable func() (string, error)) (string, error)
414	420
415	421		func initStartupContextWithTrace(cfg *config.Config) context.Context {
416	422		logging.InitStartupTrace(cfg.Logging.Level)
417		-	logging.Trace().Mark("config_loaded")
418	423
419	424		ctx := initStartupContext(cfg)
420	425		bootstrapLog := logging.FromContext(ctx)

 }
 func main() {
+	// This is intentionally before subprocess detection: each process records
+	// its own first observable main event before CEF can take over execution.
+	logging.InitStartupTrace("")
+	logging.Trace().Mark("process_entry")
 	// CEF subprocess handling: when CEF re-launches this binary with
 	// --type=renderer/gpu/etc, we must call ExecuteProcess before anything
 	// else (Cobra, config, arg stripping). We only treat a leading Chromium
 		cfg = initConfig()
 		configureBrowserLaunchRelay(cfg)
 	}
+	logging.Trace().Mark("config_complete")
 	timer.Mark("config")
 	ctx := initStartupContextWithTrace(cfg)
 func initStartupContextWithTrace(cfg *config.Config) context.Context {
 	logging.InitStartupTrace(cfg.Logging.Level)
-	logging.Trace().Mark("config_loaded")
 	ctx := initStartupContext(cfg)
 	bootstrapLog := logging.FromContext(ctx)

A docs/first-presentation.md +50 -0

@@ -0,0 +1,50 @@
	1	+	# First presentation startup trace
	2	+
	3	+	Dumber records one cold-start timeline for each GUI process. The trace begins
	4	+	at `process_entry`, before CEF subprocess handling, and accepts these one-shot
	5	+	milestones only in order:
	6	+
	7	+	1. `process_entry`
	8	+	2. `config_complete`
	9	+	3. `cef_library_load_begin` (immediately before `InitWithApp`)
	10	+	4. `cef_initialized`
	11	+	5. `browser_create_requested`
	12	+	6. `first_accelerated_paint_received`
	13	+	7. `first_dmabuf_texture_swap` (after `GtkPicture.SetPaintable` succeeds)
	14	+	8. `first_gtk_presentation` (the subsequent GTK frame-clock after-paint)
	15	+
	16	+	CEF library-load completion is intentionally not recorded: `InitWithApp` is an
	17	+	opaque operation. Duplicate, unknown, and out-of-order transitions are
	18	+	rejected. At the last milestone Dumber emits exactly one normal-level JSON
	19	+	summary (`startup_trace: first presentation`) with the selected `backend`, an
	20	+	`incomplete_reason`, total milliseconds, and monotonic milestones.
	21	+
	22	+	## Reproducible collection
	23	+
	24	+	Build the candidate, then run:
	25	+
	26	+	```bash
	27	+	DUMBER_FIRST_PRESENTATION_BIN="$PWD/dist/dumber" \
	28	+	DUMBER_MACHINE_GPU_PROFILE=integrated-gpu \
	29	+	scripts/collect_first_presentation.sh
	30	+	```
	31	+
	32	+	By default each collection is a fresh directory below
	33	+	`$XDG_STATE_HOME/dumber/roadmap-evidence` (or
	34	+	`$HOME/.local/state/dumber/roadmap-evidence` when `XDG_STATE_HOME` is unset),
	35	+	not in the repository. `DUMBER_FIRST_PRESENTATION_OUTPUT` may override it only
	36	+	with a new absolute directory below an existing non-symlink parent. The
	37	+	collector never clears or reuses a caller-supplied path.
	38	+
	39	+	The script requires the current display and the CEF 147 runtime at
	40	+	`~/.local/share/cef-147-runtime` (override with `DUMBER_CEF_DIR`). It performs
	41	+	exactly five bounded launches with fresh XDG homes and CEF root cache, fixes the
	42	+	DMABUF/Vulkan renderer, and writes exactly `metadata.json`, `run-01.json`
	43	+	through `run-05.json`, and `baseline.json`. Metadata includes only coarse,
	44	+	comparison-safe OS/architecture, display protocol, and machine/GPU profile
	45	+	labels. Set `DUMBER_MACHINE_GPU_PROFILE` to one of `generic-gpu`,
	46	+	`integrated-gpu`, `discrete-gpu`, `hybrid-gpu`, `virtual-gpu`, or `unknown-gpu`;
	47	+	do not use a device model or other identifier. Publish only the seven reviewed
	48	+	JSON files to an external Gist. Raw logs and temporary XDG homes are removed and
	49	+	must not be published. A missing or incomplete timeline, non-DMABUF backend, or
	50	+	invalid run fails collection.

@@ -0,0 +1,50 @@
	1	+	# First presentation startup trace
	2	+
	3	+	Dumber records one cold-start timeline for each GUI process. The trace begins
	4	+	at `process_entry`, before CEF subprocess handling, and accepts these one-shot
	5	+	milestones only in order:
	6	+
	7	+	1. `process_entry`
	8	+	2. `config_complete`
	9	+	3. `cef_library_load_begin` (immediately before `InitWithApp`)
	10	+	4. `cef_initialized`
	11	+	5. `browser_create_requested`
	12	+	6. `first_accelerated_paint_received`
	13	+	7. `first_dmabuf_texture_swap` (after `GtkPicture.SetPaintable` succeeds)
	14	+	8. `first_gtk_presentation` (the subsequent GTK frame-clock after-paint)
	15	+
	16	+	CEF library-load completion is intentionally not recorded: `InitWithApp` is an
	17	+	opaque operation. Duplicate, unknown, and out-of-order transitions are
	18	+	rejected. At the last milestone Dumber emits exactly one normal-level JSON
	19	+	summary (`startup_trace: first presentation`) with the selected `backend`, an
	20	+	`incomplete_reason`, total milliseconds, and monotonic milestones.
	21	+
	22	+	## Reproducible collection
	23	+
	24	+	Build the candidate, then run:
	25	+
	26	+	```bash
	27	+	DUMBER_FIRST_PRESENTATION_BIN="$PWD/dist/dumber" \
	28	+	DUMBER_MACHINE_GPU_PROFILE=integrated-gpu \
	29	+	scripts/collect_first_presentation.sh
	30	+	```
	31	+
	32	+	By default each collection is a fresh directory below
	33	+	`$XDG_STATE_HOME/dumber/roadmap-evidence` (or
	34	+	`$HOME/.local/state/dumber/roadmap-evidence` when `XDG_STATE_HOME` is unset),
	35	+	not in the repository. `DUMBER_FIRST_PRESENTATION_OUTPUT` may override it only
	36	+	with a new absolute directory below an existing non-symlink parent. The
	37	+	collector never clears or reuses a caller-supplied path.
	38	+
	39	+	The script requires the current display and the CEF 147 runtime at
	40	+	`~/.local/share/cef-147-runtime` (override with `DUMBER_CEF_DIR`). It performs
	41	+	exactly five bounded launches with fresh XDG homes and CEF root cache, fixes the
	42	+	DMABUF/Vulkan renderer, and writes exactly `metadata.json`, `run-01.json`
	43	+	through `run-05.json`, and `baseline.json`. Metadata includes only coarse,
	44	+	comparison-safe OS/architecture, display protocol, and machine/GPU profile
	45	+	labels. Set `DUMBER_MACHINE_GPU_PROFILE` to one of `generic-gpu`,
	46	+	`integrated-gpu`, `discrete-gpu`, `hybrid-gpu`, `virtual-gpu`, or `unknown-gpu`;
	47	+	do not use a device model or other identifier. Publish only the seven reviewed
	48	+	JSON files to an external Gist. Raw logs and temporary XDG homes are removed and
	49	+	must not be published. A missing or incomplete timeline, non-DMABUF backend, or
	50	+	invalid run fails collection.

M go.mod +1 -1


@@ -7,7 +7,7 @@ require (
7	7		github.com/andybalholm/brotli v1.2.2
8	8		github.com/bnema/purego v0.11.0-bnema.4
9	9		github.com/bnema/purego-cef v0.13.3
10		-	github.com/bnema/purego-cef2gtk v0.8.2
	10	+	github.com/bnema/purego-cef2gtk v0.8.4
11	11		github.com/bnema/purego-pipewire v0.1.4
12	12		github.com/bnema/purego-sqlite v0.1.3
13	13		github.com/bnema/puregotk v0.7.0


@@ -7,7 +7,7 @@ require (
7		github.com/andybalholm/brotli v1.2.2	7		github.com/andybalholm/brotli v1.2.2
8		github.com/bnema/purego v0.11.0-bnema.4	8		github.com/bnema/purego v0.11.0-bnema.4
9		github.com/bnema/purego-cef v0.13.3	9		github.com/bnema/purego-cef v0.13.3
10	-	github.com/bnema/purego-cef2gtk v0.8.2	10	+	github.com/bnema/purego-cef2gtk v0.8.4
11		github.com/bnema/purego-pipewire v0.1.4	11		github.com/bnema/purego-pipewire v0.1.4
12		github.com/bnema/purego-sqlite v0.1.3	12		github.com/bnema/purego-sqlite v0.1.3
13		github.com/bnema/puregotk v0.7.0	13		github.com/bnema/puregotk v0.7.0

M go.sum +8 -0 generated file: collapsed

load diff

M internal/infrastructure/cef/engine_init.go +24 -3


@@ -56,6 +56,7 @@ func NewEngine(
56	56		return nil, err
57	57		}
58	58		cef2gtk.ConfigureRenderStackEnvironment(renderStackPlan)
	59	+	logging.Trace().SetBackend(renderStackPlan.Backend.String())
59	60
60	61		settings, err := prepareCEFSettings(opts, paths, cfg, logger)
61	62		if err != nil {

@@ -146,6 +147,24 @@ func resolvedStateRoot(defaultStateRoot string, opts port.EngineOptions) string
146	147		return defaultStateRoot
147	148		}
148	149
	150	+	// configureCEFSubprocessRuntime chooses the CEF runtime used by both the
	151	+	// browser and CEF helper processes. CEF re-execs this binary for helpers before
	152	+	// Dumber can load configuration, so the selected configured runtime must be in
	153	+	// its inherited environment before InitWithApp launches any child. A caller's
	154	+	// explicit CEF_DIR remains the override for both process types.
	155	+	func configureCEFSubprocessRuntime(configured string) string {
	156	+	if explicit := os.Getenv("CEF_DIR"); explicit != "" {
	157	+	return explicit
	158	+	}
	159	+	if configured == "" {
	160	+	return ""
	161	+	}
	162	+	if err := os.Setenv("CEF_DIR", configured); err != nil {
	163	+	return configured
	164	+	}
	165	+	return configured
	166	+	}
	167	+
149	168		// prepareCEFSettings builds purecef.Settings from the engine config.
150	169		func prepareCEFSettings(
151	170		opts port.EngineOptions,

@@ -169,9 +188,7 @@ func prepareCEFSettings(
169	188		settings.MultiThreadedMessageLoop = true
170	189		settings.ExternalMessagePump = false
171	190		settings.RootCachePath = resolvedStateRoot(paths.StateRoot, opts)
172		-	if cfg.CEFDir != "" {
173		-	settings.CEFDir = cfg.CEFDir
174		-	}
	191	+	settings.CEFDir = configureCEFSubprocessRuntime(cfg.CEFDir)
175	192		if runtimeLogFile, err := prepareCEFLogFile(paths.LogFile, cfg.LogFile); err != nil {
176	193		logger.Warn().Err(err).Msg("cef: failed to prepare runtime log file")
177	194		} else {

@@ -199,9 +216,13 @@ func initializeCEF(eng Engine, settings purecef.Settings, logger zerolog.Logge
199	216		Str("env_cef_dir", os.Getenv("CEF_DIR")).
200	217		Msg("cef: runtime selection")
201	218		logger.Debug().Msg("cef: calling InitWithApp")
	219	+	// InitWithApp encapsulates loading libcef, so only the begin boundary is
	220	+	// observable here; do not invent a separate library-load completion event.
	221	+	logging.Trace().Mark("cef_library_load_begin")
202	222		if err := purecef.InitWithApp(settings, app); err != nil {
203	223		return fmt.Errorf("cef.InitWithApp: %w", err)
204	224		}
	225	+	logging.Trace().Mark("cef_initialized")
205	226		if libcefPath := loadedLibCEFPath(); libcefPath != "" {
206	227		logger.Info().Str("libcef_path", libcefPath).Msg("cef: runtime library loaded")
207	228		} else {

 		return nil, err
 	}
 	cef2gtk.ConfigureRenderStackEnvironment(renderStackPlan)
+	logging.Trace().SetBackend(renderStackPlan.Backend.String())
 	settings, err := prepareCEFSettings(opts, paths, cfg, logger)
 	if err != nil {
 	return defaultStateRoot
 }
+// configureCEFSubprocessRuntime chooses the CEF runtime used by both the
+// browser and CEF helper processes. CEF re-execs this binary for helpers before
+// Dumber can load configuration, so the selected configured runtime must be in
+// its inherited environment before InitWithApp launches any child. A caller's
+// explicit CEF_DIR remains the override for both process types.
+func configureCEFSubprocessRuntime(configured string) string {
+	if explicit := os.Getenv("CEF_DIR"); explicit != "" {
+		return explicit
+	}
+	if configured == "" {
+		return ""
+	}
+	if err := os.Setenv("CEF_DIR", configured); err != nil {
+		return configured
+	}
+	return configured
+}
 // prepareCEFSettings builds purecef.Settings from the engine config.
 func prepareCEFSettings(
 	opts port.EngineOptions,
 	settings.MultiThreadedMessageLoop = true
 	settings.ExternalMessagePump = false
 	settings.RootCachePath = resolvedStateRoot(paths.StateRoot, opts)
-	if cfg.CEFDir != "" {
+	settings.CEFDir = configureCEFSubprocessRuntime(cfg.CEFDir)
-		settings.CEFDir = cfg.CEFDir
-	}
 	if runtimeLogFile, err := prepareCEFLogFile(paths.LogFile, cfg.LogFile); err != nil {
 		logger.Warn().Err(err).Msg("cef: failed to prepare runtime log file")
 	} else {
 		Str("env_cef_dir", os.Getenv("CEF_DIR")).
 		Msg("cef: runtime selection")
 	logger.Debug().Msg("cef: calling InitWithApp")
+	// InitWithApp encapsulates loading libcef, so only the begin boundary is
+	// observable here; do not invent a separate library-load completion event.
+	logging.Trace().Mark("cef_library_load_begin")
 	if err := purecef.InitWithApp(settings, app); err != nil {
 		return fmt.Errorf("cef.InitWithApp: %w", err)
 	}
+	logging.Trace().Mark("cef_initialized")
 	if libcefPath := loadedLibCEFPath(); libcefPath != "" {
 		logger.Info().Str("libcef_path", libcefPath).Msg("cef: runtime library loaded")
 	} else {

M internal/infrastructure/cef/engine_init_test.go +16 -0


@@ -36,6 +36,22 @@ func TestResolvedStateRoot_UsesProfileDefault(t *testing.T) {
36	36		require.Equal(t, profile.CEFUserDataDir(), root)
37	37		}
38	38
	39	+	func TestConfigureCEFSubprocessRuntime_PropagatesConfiguredRuntimeBeforeInit(t *testing.T) {
	40	+	t.Setenv("CEF_DIR", "")
	41	+
	42	+	runtime := filepath.Join(t.TempDir(), "cef-147")
	43	+	require.Equal(t, runtime, configureCEFSubprocessRuntime(runtime))
	44	+	require.Equal(t, runtime, os.Getenv("CEF_DIR"))
	45	+	}
	46	+
	47	+	func TestConfigureCEFSubprocessRuntime_PreservesExplicitEnvironmentOverride(t *testing.T) {
	48	+	explicitRuntime := filepath.Join(t.TempDir(), "cef-env")
	49	+	t.Setenv("CEF_DIR", explicitRuntime)
	50	+
	51	+	require.Equal(t, explicitRuntime, configureCEFSubprocessRuntime(filepath.Join(t.TempDir(), "cef-config")))
	52	+	require.Equal(t, explicitRuntime, os.Getenv("CEF_DIR"))
	53	+	}
	54	+
39	55		func TestPrepareCEFSettings_UsesResolvedProfilePaths(t *testing.T) {
40	56		logger := zerolog.Nop()
41	57		profile := testCEFDevProfile(t)


@@ -36,6 +36,22 @@ func TestResolvedStateRoot_UsesProfileDefault(t *testing.T) {
36	require.Equal(t, profile.CEFUserDataDir(), root)	36		require.Equal(t, profile.CEFUserDataDir(), root)
37	}	37		}
38		38
		39	+	func TestConfigureCEFSubprocessRuntime_PropagatesConfiguredRuntimeBeforeInit(t *testing.T) {
		40	+	t.Setenv("CEF_DIR", "")
		41	+
		42	+	runtime := filepath.Join(t.TempDir(), "cef-147")
		43	+	require.Equal(t, runtime, configureCEFSubprocessRuntime(runtime))
		44	+	require.Equal(t, runtime, os.Getenv("CEF_DIR"))
		45	+	}
		46	+
		47	+	func TestConfigureCEFSubprocessRuntime_PreservesExplicitEnvironmentOverride(t *testing.T) {
		48	+	explicitRuntime := filepath.Join(t.TempDir(), "cef-env")
		49	+	t.Setenv("CEF_DIR", explicitRuntime)
		50	+
		51	+	require.Equal(t, explicitRuntime, configureCEFSubprocessRuntime(filepath.Join(t.TempDir(), "cef-config")))
		52	+	require.Equal(t, explicitRuntime, os.Getenv("CEF_DIR"))
		53	+	}
		54	+
39	func TestPrepareCEFSettings_UsesResolvedProfilePaths(t *testing.T) {	55		func TestPrepareCEFSettings_UsesResolvedProfilePaths(t *testing.T) {
40	logger := zerolog.Nop()	56		logger := zerolog.Nop()
41	profile := testCEFDevProfile(t)	57		profile := testCEFDevProfile(t)

M internal/infrastructure/cef/factory.go +2 -0


@@ -278,6 +278,8 @@ func (f WebViewFactory) postPendingBrowserCreate(ctx context.Context, wv WebVi
278	278		// renderer without an initial paint. We replay pending navigation from
279	279		// OnAfterCreated once the host is fully wired.
280	280		initialURL := "about:blank"
	281	+	// This is the request boundary, not the later OnAfterCreated callback.
	282	+	logging.Trace().Mark("browser_create_requested")
281	283		result := cefBrowserHostCreateBrowser(
282	284		pc.windowInfo,
283	285		pc.client,


@@ -278,6 +278,8 @@ func (f WebViewFactory) postPendingBrowserCreate(ctx context.Context, wv WebVi
278	// renderer without an initial paint. We replay pending navigation from	278		// renderer without an initial paint. We replay pending navigation from
279	// OnAfterCreated once the host is fully wired.	279		// OnAfterCreated once the host is fully wired.
280	initialURL := "about:blank"	280		initialURL := "about:blank"
		281	+	// This is the request boundary, not the later OnAfterCreated callback.
		282	+	logging.Trace().Mark("browser_create_requested")
281	result := cefBrowserHostCreateBrowser(	283		result := cefBrowserHostCreateBrowser(
282	pc.windowInfo,	284		pc.windowInfo,
283	pc.client,	285		pc.client,

M internal/infrastructure/cef/render_handler_adapter.go +35 -15


@@ -23,6 +23,26 @@ type dumberRenderHandler struct {
23	23
24	24		var _ purecef.RenderHandler = (*dumberRenderHandler)(nil)
25	25
	26	+	// startupPresentationHooks consumes the one-shot facts emitted by
	27	+	// purego-cef2gtk. The bridge owns the native DMABUF and frame-clock boundaries;
	28	+	// Dumber only records their ordered application-level timeline.
	29	+	func startupPresentationHooks() cef2gtk.Hooks {
	30	+	return cef2gtk.Hooks{
	31	+	OnFirstAcceleratedPaint: func() {
	32	+	logging.Trace().Mark("first_accelerated_paint_received")
	33	+	},
	34	+	OnFirstDMABUFTextureSwap: func() {
	35	+	logging.Trace().Mark("first_dmabuf_texture_swap")
	36	+	},
	37	+	OnFirstPresentation: func() {
	38	+	logging.Trace().MarkGTKAfterPaint()
	39	+	},
	40	+	OnDMABUFUnsupported: func() {
	41	+	logging.Trace().SetIncompleteReason("dmabuf_texture_swap_unavailable")
	42	+	},
	43	+	}
	44	+	}
	45	+
26	46		func newDumberRenderHandler(wv *WebView) purecef.RenderHandler {
27	47		if wv == nil \|\| wv.viewBridge == nil {
28	48		return nil

@@ -30,23 +50,23 @@ func newDumberRenderHandler(wv *WebView) purecef.RenderHandler {
30	50		h := &dumberRenderHandler{wv: wv}
31	51
32	52		var unsupportedPaintOnce sync.Once
33		-	h.main = wv.viewBridge.RenderHandler(cef2gtk.Hooks{
34		-	OnUnsupportedPaint: func() {
35		-	unsupportedPaintOnce.Do(func() {
36		-	if wv.ctx != nil {
37		-	logging.FromContext(wv.ctx).Warn().Msg("cef: unsupported CPU paint from accelerated bridge")
38		-	}
39		-	})
40		-	},
41		-	OnError: func(err error) {
	53	+	hooks := startupPresentationHooks()
	54	+	hooks.OnUnsupportedPaint = func() {
	55	+	unsupportedPaintOnce.Do(func() {
42	56		if wv.ctx != nil {
43		-	logging.FromContext(wv.ctx).Warn().Err(err).Msg("cef: accelerated render bridge error")
	57	+	logging.FromContext(wv.ctx).Warn().Msg("cef: unsupported CPU paint from accelerated bridge")
44	58		}
45		-	},
46		-	OnTextSelectionChanged: func(selectedText string, _ *purecef.Range) {
47		-	handleRenderTextSelectionChanged(wv, selectedText)
48		-	},
49		-	})
	59	+	})
	60	+	}
	61	+	hooks.OnError = func(err error) {
	62	+	if wv.ctx != nil {
	63	+	logging.FromContext(wv.ctx).Warn().Err(err).Msg("cef: accelerated render bridge error")
	64	+	}
	65	+	}
	66	+	hooks.OnTextSelectionChanged = func(selectedText string, _ *purecef.Range) {
	67	+	handleRenderTextSelectionChanged(wv, selectedText)
	68	+	}
	69	+	h.main = wv.viewBridge.RenderHandler(hooks)
50	70
51	71		if wv.popupSurface != nil {
52	72		var popupUnsupportedPaintOnce sync.Once

 var _ purecef.RenderHandler = (*dumberRenderHandler)(nil)
+// startupPresentationHooks consumes the one-shot facts emitted by
+// purego-cef2gtk. The bridge owns the native DMABUF and frame-clock boundaries;
+// Dumber only records their ordered application-level timeline.
+func startupPresentationHooks() cef2gtk.Hooks {
+	return cef2gtk.Hooks{
+		OnFirstAcceleratedPaint: func() {
+			logging.Trace().Mark("first_accelerated_paint_received")
+		},
+		OnFirstDMABUFTextureSwap: func() {
+			logging.Trace().Mark("first_dmabuf_texture_swap")
+		},
+		OnFirstPresentation: func() {
+			logging.Trace().MarkGTKAfterPaint()
+		},
+		OnDMABUFUnsupported: func() {
+			logging.Trace().SetIncompleteReason("dmabuf_texture_swap_unavailable")
+		},
+	}
+}
 func newDumberRenderHandler(wv *WebView) purecef.RenderHandler {
 	if wv == nil || wv.viewBridge == nil {
 		return nil
 	h := &dumberRenderHandler{wv: wv}
 	var unsupportedPaintOnce sync.Once
-	h.main = wv.viewBridge.RenderHandler(cef2gtk.Hooks{
+	hooks := startupPresentationHooks()
-		OnUnsupportedPaint: func() {
+	hooks.OnUnsupportedPaint = func() {
-			unsupportedPaintOnce.Do(func() {
+		unsupportedPaintOnce.Do(func() {
-				if wv.ctx != nil {
-					logging.FromContext(wv.ctx).Warn().Msg("cef: unsupported CPU paint from accelerated bridge")
-				}
-			})
-		},
-		OnError: func(err error) {
 			if wv.ctx != nil {
-				logging.FromContext(wv.ctx).Warn().Err(err).Msg("cef: accelerated render bridge error")
+				logging.FromContext(wv.ctx).Warn().Msg("cef: unsupported CPU paint from accelerated bridge")
 			}
-		},
+		})
-		OnTextSelectionChanged: func(selectedText string, _ *purecef.Range) {
+	}
-			handleRenderTextSelectionChanged(wv, selectedText)
+	hooks.OnError = func(err error) {
-		},
+		if wv.ctx != nil {
-	})
+			logging.FromContext(wv.ctx).Warn().Err(err).Msg("cef: accelerated render bridge error")
+		}
+	}
+	hooks.OnTextSelectionChanged = func(selectedText string, _ *purecef.Range) {
+		handleRenderTextSelectionChanged(wv, selectedText)
+	}
+	h.main = wv.viewBridge.RenderHandler(hooks)
 	if wv.popupSurface != nil {
 		var popupUnsupportedPaintOnce sync.Once

A internal/infrastructure/cef/startup_presentation_hooks_test.go +16 -0

@@ -0,0 +1,16 @@
	1	+	package cef
	2	+
	3	+	import (
	4	+	"testing"
	5	+
	6	+	"github.com/stretchr/testify/require"
	7	+	)
	8	+
	9	+	func TestStartupPresentationHooksWireEveryUpstreamFirstPresentationCallback(t *testing.T) {
	10	+	hooks := startupPresentationHooks()
	11	+
	12	+	require.NotNil(t, hooks.OnFirstAcceleratedPaint)
	13	+	require.NotNil(t, hooks.OnFirstDMABUFTextureSwap)
	14	+	require.NotNil(t, hooks.OnFirstPresentation)
	15	+	require.NotNil(t, hooks.OnDMABUFUnsupported)
	16	+	}

@@ -0,0 +1,16 @@
	1	+	package cef
	2	+
	3	+	import (
	4	+	"testing"
	5	+
	6	+	"github.com/stretchr/testify/require"
	7	+	)
	8	+
	9	+	func TestStartupPresentationHooksWireEveryUpstreamFirstPresentationCallback(t *testing.T) {
	10	+	hooks := startupPresentationHooks()
	11	+
	12	+	require.NotNil(t, hooks.OnFirstAcceleratedPaint)
	13	+	require.NotNil(t, hooks.OnFirstDMABUFTextureSwap)
	14	+	require.NotNil(t, hooks.OnFirstPresentation)
	15	+	require.NotNil(t, hooks.OnDMABUFUnsupported)
	16	+	}

A internal/logging/first_presentation_collector_test.go +301 -0

@@ -0,0 +1,301 @@
	1	+	package logging
	2	+
	3	+	import (
	4	+	"encoding/json"
	5	+	"os"
	6	+	"os/exec"
	7	+	"path/filepath"
	8	+	"strings"
	9	+	"testing"
	10	+
	11	+	"github.com/stretchr/testify/require"
	12	+	)
	13	+
	14	+	const validFirstPresentationLog = `{"message":"startup_trace: milestone","milestone":"process_entry","t_ms":0,"delta_ms":0,"time":"2026-07-14T09:00:00+02:00","machine_path":"/home/alice/private"}
	15	+	{"message":"startup_trace: milestone","milestone":"config_complete","t_ms":1,"delta_ms":1}
	16	+	{"message":"startup_trace: milestone","milestone":"cef_library_load_begin","t_ms":2,"delta_ms":1}
	17	+	{"message":"startup_trace: milestone","milestone":"cef_initialized","t_ms":3,"delta_ms":1}
	18	+	{"message":"startup_trace: milestone","milestone":"browser_create_requested","t_ms":4,"delta_ms":1}
	19	+	{"message":"startup_trace: milestone","milestone":"first_accelerated_paint_received","t_ms":5,"delta_ms":1}
	20	+	{"message":"startup_trace: milestone","milestone":"first_dmabuf_texture_swap","t_ms":6,"delta_ms":1}
	21	+	{"message":"startup_trace: milestone","milestone":"first_gtk_presentation","t_ms":7,"delta_ms":1}
	22	+	{"message":"startup_trace: first presentation","backend":"gdk-dmabuf","incomplete_reason":"","total_ms":7,"host":"alice"}`
	23	+
	24	+	func TestFirstPresentationCollectorNeverRecursivelyDeletesCallerOutput(t *testing.T) {
	25	+	repoRoot, err := filepath.Abs(filepath.Join("..", ".."))
	26	+	require.NoError(t, err)
	27	+	script, err := os.ReadFile(filepath.Join(repoRoot, "scripts", "collect_first_presentation.sh"))
	28	+	require.NoError(t, err)
	29	+	require.NotContains(t, string(script), "rm -rf \"$output\"")
	30	+	require.NotContains(t, string(script), "rm -rf -- \"$output\"")
	31	+	}
	32	+
	33	+	func TestFirstPresentationCollectorRejectsUnsafeOutputPaths(t *testing.T) {
	34	+	repoRoot, err := filepath.Abs(filepath.Join("..", ".."))
	35	+	require.NoError(t, err)
	36	+	temp := t.TempDir()
	37	+	runtime := filepath.Join(temp, "cef-147-runtime")
	38	+	require.NoError(t, os.Mkdir(runtime, 0o755))
	39	+	binary := filepath.Join(temp, "dumber")
	40	+	require.NoError(t, os.WriteFile(binary, collectorTestBinary(validFirstPresentationLog), 0o755))
	41	+	home := filepath.Join(temp, "home")
	42	+	require.NoError(t, os.Mkdir(home, 0o755))
	43	+
	44	+	unrelated := filepath.Join(temp, "unrelated")
	45	+	require.NoError(t, os.Mkdir(unrelated, 0o755))
	46	+	unrelatedSentinel := filepath.Join(unrelated, "keep")
	47	+	require.NoError(t, os.WriteFile(unrelatedSentinel, []byte("do not delete"), 0o600))
	48	+
	49	+	safeParent := filepath.Join(temp, "safe")
	50	+	require.NoError(t, os.Mkdir(safeParent, 0o755))
	51	+	parentSentinel := filepath.Join(safeParent, "keep")
	52	+	require.NoError(t, os.WriteFile(parentSentinel, []byte("do not delete"), 0o600))
	53	+
	54	+	external := filepath.Join(temp, "external")
	55	+	require.NoError(t, os.Mkdir(external, 0o755))
	56	+	externalSentinel := filepath.Join(external, "keep")
	57	+	require.NoError(t, os.WriteFile(externalSentinel, []byte("do not delete"), 0o600))
	58	+	link := filepath.Join(temp, "link")
	59	+	require.NoError(t, os.Symlink(external, link))
	60	+
	61	+	for _, test := range []struct {
	62	+	name string
	63	+	output string
	64	+	verify func(t *testing.T)
	65	+	}{
	66	+	{name: "empty", output: ""},
	67	+	{name: "root", output: "/"},
	68	+	{name: "home", output: home},
	69	+	{name: "existing unrelated directory", output: unrelated, verify: func(t *testing.T) {
	70	+	requireFileContents(t, unrelatedSentinel, "do not delete")
	71	+	}},
	72	+	{name: "parent traversal", output: safeParent + "/../escaped", verify: func(t *testing.T) {
	73	+	requireFileContents(t, parentSentinel, "do not delete")
	74	+	require.NoFileExists(t, filepath.Join(temp, "escaped"))
	75	+	}},
	76	+	{name: "symlink escape", output: filepath.Join(link, "escaped"), verify: func(t *testing.T) {
	77	+	requireFileContents(t, externalSentinel, "do not delete")
	78	+	require.NoFileExists(t, filepath.Join(external, "escaped"))
	79	+	}},
	80	+	} {
	81	+	t.Run(test.name, func(t *testing.T) {
	82	+	cmd := exec.Command(filepath.Join(repoRoot, "scripts", "collect_first_presentation.sh"))
	83	+	// An isolated directory prevents a regression from reaching the tracked
	84	+	// default artifact path while this test proves output validation is first.
	85	+	cmd.Dir = temp
	86	+	cmd.Env = append(os.Environ(),
	87	+	"HOME="+home,
	88	+	"DISPLAY=:test",
	89	+	"DUMBER_CEF_DIR="+runtime,
	90	+	"DUMBER_FIRST_PRESENTATION_BIN="+binary,
	91	+	"DUMBER_FIRST_PRESENTATION_OUTPUT="+test.output,
	92	+	)
	93	+	result, err := cmd.CombinedOutput()
	94	+	require.Errorf(t, err, "collector accepted unsafe output %q: %s", test.output, result)
	95	+	require.Contains(t, string(result), "unsafe output path")
	96	+	if test.verify != nil {
	97	+	test.verify(t)
	98	+	}
	99	+	})
	100	+	}
	101	+	}
	102	+
	103	+	func requireFileContents(t *testing.T, path, want string) {
	104	+	t.Helper()
	105	+	contents, err := os.ReadFile(path)
	106	+	require.NoError(t, err)
	107	+	require.Equal(t, want, string(contents))
	108	+	}
	109	+
	110	+	func TestFirstPresentationCollectorSanitizesMachineLocalValues(t *testing.T) {
	111	+	repoRoot, err := filepath.Abs(filepath.Join("..", ".."))
	112	+	require.NoError(t, err)
	113	+	temp := t.TempDir()
	114	+	runtime := filepath.Join(temp, "cef-147-runtime")
	115	+	require.NoError(t, os.Mkdir(runtime, 0o755))
	116	+
	117	+	binary := filepath.Join(temp, "dumber")
	118	+	require.NoError(t, os.WriteFile(binary, collectorTestBinary(validFirstPresentationLog), 0o755))
	119	+
	120	+	output := filepath.Join(temp, "artifacts")
	121	+	cmd := exec.Command(filepath.Join(repoRoot, "scripts", "collect_first_presentation.sh"))
	122	+	cmd.Dir = repoRoot
	123	+	cmd.Env = append(os.Environ(),
	124	+	"DISPLAY=:test",
	125	+	"WAYLAND_DISPLAY=",
	126	+	"DUMBER_CEF_DIR="+runtime,
	127	+	"DUMBER_FIRST_PRESENTATION_BIN="+binary,
	128	+	"DUMBER_FIRST_PRESENTATION_OUTPUT="+output,
	129	+	"DUMBER_FIRST_PRESENTATION_TIMEOUT_SECONDS=1",
	130	+	"DUMBER_MACHINE_GPU_PROFILE=integrated-gpu",
	131	+	)
	132	+	result, err := cmd.CombinedOutput()
	133	+	require.NoErrorf(t, err, "collector failed: %s", result)
	134	+
	135	+	var artifacts strings.Builder
	136	+	for _, name := range append([]string{"metadata.json", "baseline.json"}, runArtifactNames()...) {
	137	+	artifactContents, readErr := os.ReadFile(filepath.Join(output, name))
	138	+	require.NoError(t, readErr)
	139	+	artifacts.Write(artifactContents)
	140	+	}
	141	+	for _, forbidden := range []string{"/home/", temp, "alice", "machine_path", `"time"`} {
	142	+	require.NotContainsf(t, artifacts.String(), forbidden, "committed artifact leaked %q", forbidden)
	143	+	}
	144	+	for _, required := range []string{
	145	+	`"measured_source_revision"`,
	146	+	`"tag": "v0.8.4"`,
	147	+	`"revision": "f217ece342dea3ef2a3f98671fcd16a39ad0037d"`,
	148	+	} {
	149	+	require.Contains(t, artifacts.String(), required)
	150	+	}
	151	+
	152	+	var metadata struct {
	153	+	Comparison struct {
	154	+	OS string `json:"os"`
	155	+	Architecture string `json:"architecture"`
	156	+	DisplayProtocol string `json:"display_protocol"`
	157	+	MachineGPUProfile string `json:"machine_gpu_profile"`
	158	+	} `json:"comparison"`
	159	+	}
	160	+	contents, err := os.ReadFile(filepath.Join(output, "metadata.json"))
	161	+	require.NoError(t, err)
	162	+	require.NoError(t, json.Unmarshal(contents, &metadata))
	163	+	require.NotEmpty(t, metadata.Comparison.OS)
	164	+	require.NotEmpty(t, metadata.Comparison.Architecture)
	165	+	require.Equal(t, "x11", metadata.Comparison.DisplayProtocol)
	166	+	require.Equal(t, "integrated-gpu", metadata.Comparison.MachineGPUProfile)
	167	+	}
	168	+
	169	+	func TestFirstPresentationCollectorDefaultsToXDGStateEvidenceDirectory(t *testing.T) {
	170	+	repoRoot, err := filepath.Abs(filepath.Join("..", ".."))
	171	+	require.NoError(t, err)
	172	+	temp := t.TempDir()
	173	+	runtime := filepath.Join(temp, "cef-147-runtime")
	174	+	require.NoError(t, os.Mkdir(runtime, 0o755))
	175	+	binary := filepath.Join(temp, "dumber")
	176	+	require.NoError(t, os.WriteFile(binary, collectorTestBinary(validFirstPresentationLog), 0o755))
	177	+	stateHome := filepath.Join(temp, "state")
	178	+
	179	+	cmd := exec.Command(filepath.Join(repoRoot, "scripts", "collect_first_presentation.sh"))
	180	+	cmd.Dir = repoRoot
	181	+	cmd.Env = append(envWithout("DUMBER_FIRST_PRESENTATION_OUTPUT"),
	182	+	"DISPLAY=:test",
	183	+	"WAYLAND_DISPLAY=",
	184	+	"DUMBER_CEF_DIR="+runtime,
	185	+	"DUMBER_FIRST_PRESENTATION_BIN="+binary,
	186	+	"DUMBER_FIRST_PRESENTATION_TIMEOUT_SECONDS=1",
	187	+	"DUMBER_MACHINE_GPU_PROFILE=integrated-gpu",
	188	+	"XDG_STATE_HOME="+stateHome,
	189	+	)
	190	+	result, err := cmd.CombinedOutput()
	191	+	require.NoErrorf(t, err, "collector failed: %s", result)
	192	+
	193	+	evidenceRoot := filepath.Join(stateHome, "dumber", "roadmap-evidence")
	194	+	entries, err := os.ReadDir(evidenceRoot)
	195	+	require.NoError(t, err)
	196	+	require.Len(t, entries, 1)
	197	+	require.True(t, entries[0].IsDir())
	198	+	require.FileExists(t, filepath.Join(evidenceRoot, entries[0].Name(), "metadata.json"))
	199	+	require.NotContains(t, string(result), filepath.Join(repoRoot, "phase1"))
	200	+	}
	201	+
	202	+	func envWithout(name string) []string {
	203	+	prefix := name + "="
	204	+	var environment []string
	205	+	for _, entry := range os.Environ() {
	206	+	if !strings.HasPrefix(entry, prefix) {
	207	+	environment = append(environment, entry)
	208	+	}
	209	+	}
	210	+	return environment
	211	+	}
	212	+
	213	+	func TestFirstPresentationCollectorReadsProvenanceWithScopedGitSafeDirectory(t *testing.T) {
	214	+	repoRoot, err := filepath.Abs(filepath.Join("..", ".."))
	215	+	require.NoError(t, err)
	216	+	temp := t.TempDir()
	217	+	runtime := filepath.Join(temp, "cef-147-runtime")
	218	+	require.NoError(t, os.Mkdir(runtime, 0o755))
	219	+	binary := filepath.Join(temp, "dumber")
	220	+	require.NoError(t, os.WriteFile(binary, collectorTestBinary(validFirstPresentationLog), 0o755))
	221	+	gitDir := filepath.Join(temp, "bin")
	222	+	require.NoError(t, os.Mkdir(gitDir, 0o755))
	223	+	git := filepath.Join(gitDir, "git")
	224	+	require.NoError(t, os.WriteFile(git, []byte(`#!/bin/sh
	225	+	if [ "$1" = "-c" ] && [ "$2" = "safe.directory=$EXPECTED_SAFE_DIRECTORY" ] && [ "$3" = "rev-parse" ] && [ "$4" = "HEAD" ]; then
	226	+	echo 0123456789abcdef0123456789abcdef01234567
	227	+	exit 0
	228	+	fi
	229	+	echo "fatal: detected dubious ownership in repository" >&2
	230	+	exit 128
	231	+	`), 0o755))
	232	+
	233	+	output := filepath.Join(temp, "artifacts")
	234	+	cmd := exec.Command(filepath.Join(repoRoot, "scripts", "collect_first_presentation.sh"))
	235	+	cmd.Dir = repoRoot
	236	+	cmd.Env = append(os.Environ(),
	237	+	"DISPLAY=:test",
	238	+	"DUMBER_CEF_DIR="+runtime,
	239	+	"DUMBER_FIRST_PRESENTATION_BIN="+binary,
	240	+	"DUMBER_FIRST_PRESENTATION_OUTPUT="+output,
	241	+	"DUMBER_FIRST_PRESENTATION_TIMEOUT_SECONDS=1",
	242	+	"EXPECTED_SAFE_DIRECTORY="+repoRoot,
	243	+	"PATH="+gitDir+":"+os.Getenv("PATH"),
	244	+	)
	245	+	result, err := cmd.CombinedOutput()
	246	+	require.NoErrorf(t, err, "collector failed: %s", result)
	247	+
	248	+	var metadata struct {
	249	+	MeasuredSourceRevision string `json:"measured_source_revision"`
	250	+	}
	251	+	contents, err := os.ReadFile(filepath.Join(output, "metadata.json"))
	252	+	require.NoError(t, err)
	253	+	require.NoError(t, json.Unmarshal(contents, &metadata))
	254	+	require.Equal(t, "0123456789abcdef0123456789abcdef01234567", metadata.MeasuredSourceRevision)
	255	+	}
	256	+
	257	+	func TestFirstPresentationCollectorRejectsInconsistentTiming(t *testing.T) {
	258	+	repoRoot, err := filepath.Abs(filepath.Join("..", ".."))
	259	+	require.NoError(t, err)
	260	+
	261	+	for _, test := range []struct {
	262	+	name string
	263	+	old string
	264	+	new string
	265	+	}{
	266	+	{name: "non-integer delta", old: `"delta_ms":1}`, new: `"delta_ms":"1"}`},
	267	+	{name: "incorrect delta", old: `"delta_ms":1}`, new: `"delta_ms":2}`},
	268	+	{name: "non-integer summary total", old: `"total_ms":7`, new: `"total_ms":7.5`},
	269	+	{name: "incorrect summary total", old: `"total_ms":7`, new: `"total_ms":8`},
	270	+	} {
	271	+	t.Run(test.name, func(t *testing.T) {
	272	+	temp := t.TempDir()
	273	+	runtime := filepath.Join(temp, "cef-147-runtime")
	274	+	require.NoError(t, os.Mkdir(runtime, 0o755))
	275	+	binary := filepath.Join(temp, "dumber")
	276	+	log := strings.Replace(validFirstPresentationLog, test.old, test.new, 1)
	277	+	require.NoError(t, os.WriteFile(binary, collectorTestBinary(log), 0o755))
	278	+
	279	+	cmd := exec.Command(filepath.Join(repoRoot, "scripts", "collect_first_presentation.sh"))
	280	+	cmd.Dir = repoRoot
	281	+	cmd.Env = append(os.Environ(),
	282	+	"DISPLAY=:test",
	283	+	"DUMBER_CEF_DIR="+runtime,
	284	+	"DUMBER_FIRST_PRESENTATION_BIN="+binary,
	285	+	"DUMBER_FIRST_PRESENTATION_OUTPUT="+filepath.Join(temp, "artifacts"),
	286	+	"DUMBER_FIRST_PRESENTATION_TIMEOUT_SECONDS=1",
	287	+	)
	288	+	result, err := cmd.CombinedOutput()
	289	+	require.Errorf(t, err, "collector accepted malformed timing artifact: %s", result)
	290	+	require.Contains(t, string(result), "invalid or incomplete non-DMABUF timeline")
	291	+	})
	292	+	}
	293	+	}
	294	+
	295	+	func collectorTestBinary(log string) []byte {
	296	+	return []byte("#!/bin/sh\ncat <<'EOF'\n" + log + "\nEOF\nexit 139\n")
	297	+	}
	298	+
	299	+	func runArtifactNames() []string {
	300	+	return []string{"run-01.json", "run-02.json", "run-03.json", "run-04.json", "run-05.json"}
	301	+	}

@@ -0,0 +1,301 @@
	1	+	package logging
	2	+
	3	+	import (
	4	+	"encoding/json"
	5	+	"os"
	6	+	"os/exec"
	7	+	"path/filepath"
	8	+	"strings"
	9	+	"testing"
	10	+
	11	+	"github.com/stretchr/testify/require"
	12	+	)
	13	+
	14	+	const validFirstPresentationLog = `{"message":"startup_trace: milestone","milestone":"process_entry","t_ms":0,"delta_ms":0,"time":"2026-07-14T09:00:00+02:00","machine_path":"/home/alice/private"}
	15	+	{"message":"startup_trace: milestone","milestone":"config_complete","t_ms":1,"delta_ms":1}
	16	+	{"message":"startup_trace: milestone","milestone":"cef_library_load_begin","t_ms":2,"delta_ms":1}
	17	+	{"message":"startup_trace: milestone","milestone":"cef_initialized","t_ms":3,"delta_ms":1}
	18	+	{"message":"startup_trace: milestone","milestone":"browser_create_requested","t_ms":4,"delta_ms":1}
	19	+	{"message":"startup_trace: milestone","milestone":"first_accelerated_paint_received","t_ms":5,"delta_ms":1}
	20	+	{"message":"startup_trace: milestone","milestone":"first_dmabuf_texture_swap","t_ms":6,"delta_ms":1}
	21	+	{"message":"startup_trace: milestone","milestone":"first_gtk_presentation","t_ms":7,"delta_ms":1}
	22	+	{"message":"startup_trace: first presentation","backend":"gdk-dmabuf","incomplete_reason":"","total_ms":7,"host":"alice"}`
	23	+
	24	+	func TestFirstPresentationCollectorNeverRecursivelyDeletesCallerOutput(t *testing.T) {
	25	+	repoRoot, err := filepath.Abs(filepath.Join("..", ".."))
	26	+	require.NoError(t, err)
	27	+	script, err := os.ReadFile(filepath.Join(repoRoot, "scripts", "collect_first_presentation.sh"))
	28	+	require.NoError(t, err)
	29	+	require.NotContains(t, string(script), "rm -rf \"$output\"")
	30	+	require.NotContains(t, string(script), "rm -rf -- \"$output\"")
	31	+	}
	32	+
	33	+	func TestFirstPresentationCollectorRejectsUnsafeOutputPaths(t *testing.T) {
	34	+	repoRoot, err := filepath.Abs(filepath.Join("..", ".."))
	35	+	require.NoError(t, err)
	36	+	temp := t.TempDir()
	37	+	runtime := filepath.Join(temp, "cef-147-runtime")
	38	+	require.NoError(t, os.Mkdir(runtime, 0o755))
	39	+	binary := filepath.Join(temp, "dumber")
	40	+	require.NoError(t, os.WriteFile(binary, collectorTestBinary(validFirstPresentationLog), 0o755))
	41	+	home := filepath.Join(temp, "home")
	42	+	require.NoError(t, os.Mkdir(home, 0o755))
	43	+
	44	+	unrelated := filepath.Join(temp, "unrelated")
	45	+	require.NoError(t, os.Mkdir(unrelated, 0o755))
	46	+	unrelatedSentinel := filepath.Join(unrelated, "keep")
	47	+	require.NoError(t, os.WriteFile(unrelatedSentinel, []byte("do not delete"), 0o600))
	48	+
	49	+	safeParent := filepath.Join(temp, "safe")
	50	+	require.NoError(t, os.Mkdir(safeParent, 0o755))
	51	+	parentSentinel := filepath.Join(safeParent, "keep")
	52	+	require.NoError(t, os.WriteFile(parentSentinel, []byte("do not delete"), 0o600))
	53	+
	54	+	external := filepath.Join(temp, "external")
	55	+	require.NoError(t, os.Mkdir(external, 0o755))
	56	+	externalSentinel := filepath.Join(external, "keep")
	57	+	require.NoError(t, os.WriteFile(externalSentinel, []byte("do not delete"), 0o600))
	58	+	link := filepath.Join(temp, "link")
	59	+	require.NoError(t, os.Symlink(external, link))
	60	+
	61	+	for _, test := range []struct {
	62	+	name string
	63	+	output string
	64	+	verify func(t *testing.T)
	65	+	}{
	66	+	{name: "empty", output: ""},
	67	+	{name: "root", output: "/"},
	68	+	{name: "home", output: home},
	69	+	{name: "existing unrelated directory", output: unrelated, verify: func(t *testing.T) {
	70	+	requireFileContents(t, unrelatedSentinel, "do not delete")
	71	+	}},
	72	+	{name: "parent traversal", output: safeParent + "/../escaped", verify: func(t *testing.T) {
	73	+	requireFileContents(t, parentSentinel, "do not delete")
	74	+	require.NoFileExists(t, filepath.Join(temp, "escaped"))
	75	+	}},
	76	+	{name: "symlink escape", output: filepath.Join(link, "escaped"), verify: func(t *testing.T) {
	77	+	requireFileContents(t, externalSentinel, "do not delete")
	78	+	require.NoFileExists(t, filepath.Join(external, "escaped"))
	79	+	}},
	80	+	} {
	81	+	t.Run(test.name, func(t *testing.T) {
	82	+	cmd := exec.Command(filepath.Join(repoRoot, "scripts", "collect_first_presentation.sh"))
	83	+	// An isolated directory prevents a regression from reaching the tracked
	84	+	// default artifact path while this test proves output validation is first.
	85	+	cmd.Dir = temp
	86	+	cmd.Env = append(os.Environ(),
	87	+	"HOME="+home,
	88	+	"DISPLAY=:test",
	89	+	"DUMBER_CEF_DIR="+runtime,
	90	+	"DUMBER_FIRST_PRESENTATION_BIN="+binary,
	91	+	"DUMBER_FIRST_PRESENTATION_OUTPUT="+test.output,
	92	+	)
	93	+	result, err := cmd.CombinedOutput()
	94	+	require.Errorf(t, err, "collector accepted unsafe output %q: %s", test.output, result)
	95	+	require.Contains(t, string(result), "unsafe output path")
	96	+	if test.verify != nil {
	97	+	test.verify(t)
	98	+	}
	99	+	})
	100	+	}
	101	+	}
	102	+
	103	+	func requireFileContents(t *testing.T, path, want string) {
	104	+	t.Helper()
	105	+	contents, err := os.ReadFile(path)
	106	+	require.NoError(t, err)
	107	+	require.Equal(t, want, string(contents))
	108	+	}
	109	+
	110	+	func TestFirstPresentationCollectorSanitizesMachineLocalValues(t *testing.T) {
	111	+	repoRoot, err := filepath.Abs(filepath.Join("..", ".."))
	112	+	require.NoError(t, err)
	113	+	temp := t.TempDir()
	114	+	runtime := filepath.Join(temp, "cef-147-runtime")
	115	+	require.NoError(t, os.Mkdir(runtime, 0o755))
	116	+
	117	+	binary := filepath.Join(temp, "dumber")
	118	+	require.NoError(t, os.WriteFile(binary, collectorTestBinary(validFirstPresentationLog), 0o755))
	119	+
	120	+	output := filepath.Join(temp, "artifacts")
	121	+	cmd := exec.Command(filepath.Join(repoRoot, "scripts", "collect_first_presentation.sh"))
	122	+	cmd.Dir = repoRoot
	123	+	cmd.Env = append(os.Environ(),
	124	+	"DISPLAY=:test",
	125	+	"WAYLAND_DISPLAY=",
	126	+	"DUMBER_CEF_DIR="+runtime,
	127	+	"DUMBER_FIRST_PRESENTATION_BIN="+binary,
	128	+	"DUMBER_FIRST_PRESENTATION_OUTPUT="+output,
	129	+	"DUMBER_FIRST_PRESENTATION_TIMEOUT_SECONDS=1",
	130	+	"DUMBER_MACHINE_GPU_PROFILE=integrated-gpu",
	131	+	)
	132	+	result, err := cmd.CombinedOutput()
	133	+	require.NoErrorf(t, err, "collector failed: %s", result)
	134	+
	135	+	var artifacts strings.Builder
	136	+	for _, name := range append([]string{"metadata.json", "baseline.json"}, runArtifactNames()...) {
	137	+	artifactContents, readErr := os.ReadFile(filepath.Join(output, name))
	138	+	require.NoError(t, readErr)
	139	+	artifacts.Write(artifactContents)
	140	+	}
	141	+	for _, forbidden := range []string{"/home/", temp, "alice", "machine_path", `"time"`} {
	142	+	require.NotContainsf(t, artifacts.String(), forbidden, "committed artifact leaked %q", forbidden)
	143	+	}
	144	+	for _, required := range []string{
	145	+	`"measured_source_revision"`,
	146	+	`"tag": "v0.8.4"`,
	147	+	`"revision": "f217ece342dea3ef2a3f98671fcd16a39ad0037d"`,
	148	+	} {
	149	+	require.Contains(t, artifacts.String(), required)
	150	+	}
	151	+
	152	+	var metadata struct {
	153	+	Comparison struct {
	154	+	OS string `json:"os"`
	155	+	Architecture string `json:"architecture"`
	156	+	DisplayProtocol string `json:"display_protocol"`
	157	+	MachineGPUProfile string `json:"machine_gpu_profile"`
	158	+	} `json:"comparison"`
	159	+	}
	160	+	contents, err := os.ReadFile(filepath.Join(output, "metadata.json"))
	161	+	require.NoError(t, err)
	162	+	require.NoError(t, json.Unmarshal(contents, &metadata))
	163	+	require.NotEmpty(t, metadata.Comparison.OS)
	164	+	require.NotEmpty(t, metadata.Comparison.Architecture)
	165	+	require.Equal(t, "x11", metadata.Comparison.DisplayProtocol)
	166	+	require.Equal(t, "integrated-gpu", metadata.Comparison.MachineGPUProfile)
	167	+	}
	168	+
	169	+	func TestFirstPresentationCollectorDefaultsToXDGStateEvidenceDirectory(t *testing.T) {
	170	+	repoRoot, err := filepath.Abs(filepath.Join("..", ".."))
	171	+	require.NoError(t, err)
	172	+	temp := t.TempDir()
	173	+	runtime := filepath.Join(temp, "cef-147-runtime")
	174	+	require.NoError(t, os.Mkdir(runtime, 0o755))
	175	+	binary := filepath.Join(temp, "dumber")
	176	+	require.NoError(t, os.WriteFile(binary, collectorTestBinary(validFirstPresentationLog), 0o755))
	177	+	stateHome := filepath.Join(temp, "state")
	178	+
	179	+	cmd := exec.Command(filepath.Join(repoRoot, "scripts", "collect_first_presentation.sh"))
	180	+	cmd.Dir = repoRoot
	181	+	cmd.Env = append(envWithout("DUMBER_FIRST_PRESENTATION_OUTPUT"),
	182	+	"DISPLAY=:test",
	183	+	"WAYLAND_DISPLAY=",
	184	+	"DUMBER_CEF_DIR="+runtime,
	185	+	"DUMBER_FIRST_PRESENTATION_BIN="+binary,
	186	+	"DUMBER_FIRST_PRESENTATION_TIMEOUT_SECONDS=1",
	187	+	"DUMBER_MACHINE_GPU_PROFILE=integrated-gpu",
	188	+	"XDG_STATE_HOME="+stateHome,
	189	+	)
	190	+	result, err := cmd.CombinedOutput()
	191	+	require.NoErrorf(t, err, "collector failed: %s", result)
	192	+
	193	+	evidenceRoot := filepath.Join(stateHome, "dumber", "roadmap-evidence")
	194	+	entries, err := os.ReadDir(evidenceRoot)
	195	+	require.NoError(t, err)
	196	+	require.Len(t, entries, 1)
	197	+	require.True(t, entries[0].IsDir())
	198	+	require.FileExists(t, filepath.Join(evidenceRoot, entries[0].Name(), "metadata.json"))
	199	+	require.NotContains(t, string(result), filepath.Join(repoRoot, "phase1"))
	200	+	}
	201	+
	202	+	func envWithout(name string) []string {
	203	+	prefix := name + "="
	204	+	var environment []string
	205	+	for _, entry := range os.Environ() {
	206	+	if !strings.HasPrefix(entry, prefix) {
	207	+	environment = append(environment, entry)
	208	+	}
	209	+	}
	210	+	return environment
	211	+	}
	212	+
	213	+	func TestFirstPresentationCollectorReadsProvenanceWithScopedGitSafeDirectory(t *testing.T) {
	214	+	repoRoot, err := filepath.Abs(filepath.Join("..", ".."))
	215	+	require.NoError(t, err)
	216	+	temp := t.TempDir()
	217	+	runtime := filepath.Join(temp, "cef-147-runtime")
	218	+	require.NoError(t, os.Mkdir(runtime, 0o755))
	219	+	binary := filepath.Join(temp, "dumber")
	220	+	require.NoError(t, os.WriteFile(binary, collectorTestBinary(validFirstPresentationLog), 0o755))
	221	+	gitDir := filepath.Join(temp, "bin")
	222	+	require.NoError(t, os.Mkdir(gitDir, 0o755))
	223	+	git := filepath.Join(gitDir, "git")
	224	+	require.NoError(t, os.WriteFile(git, []byte(`#!/bin/sh
	225	+	if [ "$1" = "-c" ] && [ "$2" = "safe.directory=$EXPECTED_SAFE_DIRECTORY" ] && [ "$3" = "rev-parse" ] && [ "$4" = "HEAD" ]; then
	226	+	echo 0123456789abcdef0123456789abcdef01234567
	227	+	exit 0
	228	+	fi
	229	+	echo "fatal: detected dubious ownership in repository" >&2
	230	+	exit 128
	231	+	`), 0o755))
	232	+
	233	+	output := filepath.Join(temp, "artifacts")
	234	+	cmd := exec.Command(filepath.Join(repoRoot, "scripts", "collect_first_presentation.sh"))
	235	+	cmd.Dir = repoRoot
	236	+	cmd.Env = append(os.Environ(),
	237	+	"DISPLAY=:test",
	238	+	"DUMBER_CEF_DIR="+runtime,
	239	+	"DUMBER_FIRST_PRESENTATION_BIN="+binary,
	240	+	"DUMBER_FIRST_PRESENTATION_OUTPUT="+output,
	241	+	"DUMBER_FIRST_PRESENTATION_TIMEOUT_SECONDS=1",
	242	+	"EXPECTED_SAFE_DIRECTORY="+repoRoot,
	243	+	"PATH="+gitDir+":"+os.Getenv("PATH"),
	244	+	)
	245	+	result, err := cmd.CombinedOutput()
	246	+	require.NoErrorf(t, err, "collector failed: %s", result)
	247	+
	248	+	var metadata struct {
	249	+	MeasuredSourceRevision string `json:"measured_source_revision"`
	250	+	}
	251	+	contents, err := os.ReadFile(filepath.Join(output, "metadata.json"))
	252	+	require.NoError(t, err)
	253	+	require.NoError(t, json.Unmarshal(contents, &metadata))
	254	+	require.Equal(t, "0123456789abcdef0123456789abcdef01234567", metadata.MeasuredSourceRevision)
	255	+	}
	256	+
	257	+	func TestFirstPresentationCollectorRejectsInconsistentTiming(t *testing.T) {
	258	+	repoRoot, err := filepath.Abs(filepath.Join("..", ".."))
	259	+	require.NoError(t, err)
	260	+
	261	+	for _, test := range []struct {
	262	+	name string
	263	+	old string
	264	+	new string
	265	+	}{
	266	+	{name: "non-integer delta", old: `"delta_ms":1}`, new: `"delta_ms":"1"}`},
	267	+	{name: "incorrect delta", old: `"delta_ms":1}`, new: `"delta_ms":2}`},
	268	+	{name: "non-integer summary total", old: `"total_ms":7`, new: `"total_ms":7.5`},
	269	+	{name: "incorrect summary total", old: `"total_ms":7`, new: `"total_ms":8`},
	270	+	} {
	271	+	t.Run(test.name, func(t *testing.T) {
	272	+	temp := t.TempDir()
	273	+	runtime := filepath.Join(temp, "cef-147-runtime")
	274	+	require.NoError(t, os.Mkdir(runtime, 0o755))
	275	+	binary := filepath.Join(temp, "dumber")
	276	+	log := strings.Replace(validFirstPresentationLog, test.old, test.new, 1)
	277	+	require.NoError(t, os.WriteFile(binary, collectorTestBinary(log), 0o755))
	278	+
	279	+	cmd := exec.Command(filepath.Join(repoRoot, "scripts", "collect_first_presentation.sh"))
	280	+	cmd.Dir = repoRoot
	281	+	cmd.Env = append(os.Environ(),
	282	+	"DISPLAY=:test",
	283	+	"DUMBER_CEF_DIR="+runtime,
	284	+	"DUMBER_FIRST_PRESENTATION_BIN="+binary,
	285	+	"DUMBER_FIRST_PRESENTATION_OUTPUT="+filepath.Join(temp, "artifacts"),
	286	+	"DUMBER_FIRST_PRESENTATION_TIMEOUT_SECONDS=1",
	287	+	)
	288	+	result, err := cmd.CombinedOutput()
	289	+	require.Errorf(t, err, "collector accepted malformed timing artifact: %s", result)
	290	+	require.Contains(t, string(result), "invalid or incomplete non-DMABUF timeline")
	291	+	})
	292	+	}
	293	+	}
	294	+
	295	+	func collectorTestBinary(log string) []byte {
	296	+	return []byte("#!/bin/sh\ncat <<'EOF'\n" + log + "\nEOF\nexit 139\n")
	297	+	}
	298	+
	299	+	func runArtifactNames() []string {
	300	+	return []string{"run-01.json", "run-02.json", "run-03.json", "run-04.json", "run-05.json"}
	301	+	}

M internal/logging/startup_trace.go +122 -134

@@ -1,32 +1,44 @@
1	1		package logging
2	2
3	3		import (
4		-	"fmt"
5		-	"strings"
6	4		"sync"
7	5		"time"
8	6
9	7		"github.com/rs/zerolog"
10	8		)
11	9
12		-	// StartupTrace tracks cold start milestones from process launch to first paint.
13		-	// Thread-safe for use across goroutines.
14		-	// Enabled only when log level is debug or trace.
	10	+	// StartupTrace records the single truthful path from process entry to the first
	11	+	// GTK presentation. It deliberately rejects unknown, duplicate, and out of
	12	+	// order milestones: accepting a convenient timestamp would make the result
	13	+	// unsuitable for cold-start measurement.
15	14		type StartupTrace struct {
16		-	mu sync.Mutex
17		-	t0 time.Time
18		-	milestones []Milestone
19		-	enabled bool
20		-	logger *zerolog.Logger
21		-	buffered []Milestone // milestones recorded before logger is set
22		-	finished bool
	15	+	mu sync.Mutex
	16	+	now func() time.Time
	17	+	t0 time.Time
	18	+	milestones []Milestone
	19	+	logger *zerolog.Logger
	20	+	buffered []Milestone
	21	+	backend string
	22	+	incompleteReason string
	23	+	summaryEmitted bool
23	24		}
24	25
25		-	// Milestone represents a timing checkpoint during startup.
	26	+	// Milestone represents a timing checkpoint measured from process entry.
26	27		type Milestone struct {
27	28		Name string
28		-	Elapsed time.Duration // time since t0
29		-	Delta time.Duration // time since previous milestone
	29	+	Elapsed time.Duration
	30	+	Delta time.Duration
	31	+	}
	32	+
	33	+	var startupMilestoneOrder = []string{
	34	+	"process_entry",
	35	+	"config_complete",
	36	+	"cef_library_load_begin",
	37	+	"cef_initialized",
	38	+	"browser_create_requested",
	39	+	"first_accelerated_paint_received",
	40	+	"first_dmabuf_texture_swap",
	41	+	"first_gtk_presentation",
30	42		}
31	43
32	44		var (

@@ -35,186 +47,162 @@ var (
35	47		globalTraceOnce sync.Once
36	48		)
37	49
38		-	// InitStartupTrace initializes the global startup trace.
39		-	// Call this as early as possible in main() to capture T0.
40		-	// The trace is enabled only if the given log level is debug or trace.
41		-	func InitStartupTrace(logLevel string) {
	50	+	func newStartupTrace(now func() time.Time) *StartupTrace {
	51	+	start := now()
	52	+	return &StartupTrace{
	53	+	now: now,
	54	+	t0: start,
	55	+	milestones: make([]Milestone, 0, len(startupMilestoneOrder)),
	56	+	buffered: make([]Milestone, 0, len(startupMilestoneOrder)),
	57	+	}
	58	+	}
	59	+
	60	+	// InitStartupTrace must be called at the first instruction in main. logLevel is
	61	+	// retained for source compatibility; this measurement is always collected so
	62	+	// its final structured summary is available at normal log level.
	63	+	func InitStartupTrace(_ string) {
42	64		globalTraceOnce.Do(func() {
43		-	enabled := logLevel == "debug" \|\| logLevel == "trace"
	65	+	trace := newStartupTrace(time.Now)
44	66		globalTraceMu.Lock()
45		-	globalTrace = &StartupTrace{
46		-	t0: time.Now(),
47		-	milestones: make([]Milestone, 0, 32),
48		-	enabled: enabled,
49		-	buffered: make([]Milestone, 0, 8),
50		-	}
	67	+	globalTrace = trace
51	68		globalTraceMu.Unlock()
52		-
53		-	if enabled {
54		-	// Record process_start as first milestone
55		-	globalTrace.Mark("process_start")
56		-	}
57	69		})
58	70		}
59	71
60		-	// Trace returns the global startup trace instance.
61		-	// Returns a no-op trace if not initialized or disabled.
	72	+	// Trace returns the process startup trace. Callers before initialization get a
	73	+	// harmless trace which rejects all transitions.
62	74		func Trace() *StartupTrace {
63	75		globalTraceMu.Lock()
64	76		defer globalTraceMu.Unlock()
65	77		if globalTrace == nil {
66		-	// Return a disabled no-op trace
67		-	return &StartupTrace{enabled: false}
	78	+	return &StartupTrace{}
68	79		}
69	80		return globalTrace
70	81		}
71	82
72		-	// SetLogger sets the logger for emitting milestone logs.
73		-	// Flushes any buffered milestones that were recorded before the logger was set.
	83	+	// SetLogger makes buffered milestones available to the process logger.
74	84		func (st StartupTrace) SetLogger(logger zerolog.Logger) {
75		-	if st == nil \|\| !st.enabled {
	85	+	if st == nil \|\| logger == nil {
76	86		return
77	87		}
78		-
79	88		st.mu.Lock()
80	89		defer st.mu.Unlock()
81		-
82	90		st.logger = logger
83		-
84		-	// Flush buffered milestones
85		-	for _, m := range st.buffered {
86		-	st.emitMilestone(m)
	91	+	for _, milestone := range st.buffered {
	92	+	st.emitMilestone(milestone)
87	93		}
88	94		st.buffered = nil
	95	+	st.emitSummaryLocked()
89	96		}
90	97
91		-	// UpdateLogger updates the logger and re-emits all milestones to the new logger.
92		-	// Call this after the session file logger is available to capture milestones in the log file.
93		-	func (st StartupTrace) UpdateLogger(logger zerolog.Logger) {
94		-	if st == nil \|\| !st.enabled {
	98	+	// UpdateLogger switches the destination without replaying events. Replaying
	99	+	// would violate the one-shot property in session logs.
	100	+	func (st StartupTrace) UpdateLogger(logger zerolog.Logger) { st.SetLogger(logger) }
	101	+
	102	+	// SetBackend records the selected presentation backend for the final summary.
	103	+	func (st *StartupTrace) SetBackend(backend string) {
	104	+	if st == nil {
95	105		return
96	106		}
97		-
98	107		st.mu.Lock()
99	108		defer st.mu.Unlock()
100		-
101		-	st.logger = logger
102		-
103		-	// Re-emit all milestones to the new logger
104		-	for _, m := range st.milestones {
105		-	st.emitMilestone(m)
106		-	}
	109	+	st.backend = backend
107	110		}
108	111
109		-	// Mark records a milestone with the given name.
110		-	// Emits a debug log line showing elapsed time and delta from previous milestone.
111		-	func (st *StartupTrace) Mark(name string) {
112		-	if st == nil \|\| !st.enabled {
	112	+	// SetIncompleteReason records why a trace cannot reach a valid DMABUF result.
	113	+	func (st *StartupTrace) SetIncompleteReason(reason string) {
	114	+	if st == nil {
113	115		return
114	116		}
115		-
116	117		st.mu.Lock()
117	118		defer st.mu.Unlock()
	119	+	if st.incompleteReason == "" {
	120	+	st.incompleteReason = reason
	121	+	}
	122	+	}
118	123
119		-	if st.finished {
120		-	return
	124	+	// Mark accepts exactly the next non-presentation startup milestone and returns
	125	+	// whether it was recorded. first_gtk_presentation is reserved for the GTK
	126	+	// frame-clock after-paint hook through MarkGTKAfterPaint.
	127	+	func (st *StartupTrace) Mark(name string) bool {
	128	+	if name == "first_gtk_presentation" {
	129	+	return false
121	130		}
	131	+	return st.mark(name)
	132	+	}
122	133
123		-	now := time.Now()
124		-	elapsed := now.Sub(st.t0)
	134	+	// MarkGTKAfterPaint records the final milestone. It is called only from the
	135	+	// upstream CEF-to-GTK bridge's first frame-clock after-paint callback.
	136	+	func (st *StartupTrace) MarkGTKAfterPaint() bool {
	137	+	return st.mark("first_gtk_presentation")
	138	+	}
125	139
126		-	var delta time.Duration
127		-	if len(st.milestones) > 0 {
128		-	delta = elapsed - st.milestones[len(st.milestones)-1].Elapsed
	140	+	// mark accepts the next milestone and is safe for callbacks from CEF and GTK
	141	+	// threads.
	142	+	func (st *StartupTrace) mark(name string) bool {
	143	+	if st == nil \|\| st.now == nil {
	144	+	return false
129	145		}
130		-
131		-	m := Milestone{
132		-	Name: name,
133		-	Elapsed: elapsed,
134		-	Delta: delta,
	146	+	st.mu.Lock()
	147	+	defer st.mu.Unlock()
	148	+	if len(st.milestones) >= len(startupMilestoneOrder) \|\| name != startupMilestoneOrder[len(st.milestones)] {
	149	+	return false
135	150		}
136		-	st.milestones = append(st.milestones, m)
137	151
138		-	if st.logger != nil {
139		-	st.emitMilestone(m)
	152	+	now := st.now()
	153	+	milestone := Milestone{Name: name, Elapsed: now.Sub(st.t0)}
	154	+	// Published fields are integer milliseconds. Compute delta on that same
	155	+	// scale so delta_ms always exactly reconstructs t_ms in collected evidence.
	156	+	previousMilliseconds := int64(0)
	157	+	if len(st.milestones) > 0 {
	158	+	previousMilliseconds = st.milestones[len(st.milestones)-1].Elapsed.Milliseconds()
	159	+	}
	160	+	milestone.Delta = time.Duration(milestone.Elapsed.Milliseconds()-previousMilliseconds) * time.Millisecond
	161	+	st.milestones = append(st.milestones, milestone)
	162	+	if st.logger == nil {
	163	+	st.buffered = append(st.buffered, milestone)
140	164		} else {
141		-	// Buffer until logger is set
142		-	st.buffered = append(st.buffered, m)
	165	+	st.emitMilestone(milestone)
143	166		}
	167	+	st.emitSummaryLocked()
	168	+	return true
144	169		}
145	170
146		-	// emitMilestone logs a single milestone. Caller must hold mutex.
147	171		func (st *StartupTrace) emitMilestone(m Milestone) {
148	172		if st.logger == nil {
149	173		return
150	174		}
151		-
152		-	elapsedMs := m.Elapsed.Milliseconds()
153		-
154		-	event := st.logger.Debug().
	175	+	st.logger.Debug().
155	176		Str("milestone", m.Name).
156		-	Int64("t_ms", elapsedMs)
157		-
158		-	if m.Delta > 0 {
159		-	event = event.Int64("delta_ms", m.Delta.Milliseconds())
160		-	}
161		-
162		-	// Format: startup_trace: milestone_name (T+123ms, +45ms)
163		-	if m.Delta > 0 {
164		-	event.Msgf("startup_trace: %s (T+%dms, +%dms)", m.Name, elapsedMs, m.Delta.Milliseconds())
165		-	} else {
166		-	event.Msgf("startup_trace: %s (T+%dms)", m.Name, elapsedMs)
167		-	}
	177	+	Int64("t_ms", m.Elapsed.Milliseconds()).
	178	+	Int64("delta_ms", m.Delta.Milliseconds()).
	179	+	Msg("startup_trace: milestone")
168	180		}
169	181
170		-	// Finish marks the startup trace as complete and emits a summary.
171		-	// Called on first_paint milestone.
172		-	func (st *StartupTrace) Finish() {
173		-	if st == nil \|\| !st.enabled {
	182	+	func (st *StartupTrace) emitSummaryLocked() {
	183	+	if st.summaryEmitted \|\| st.logger == nil \|\| len(st.milestones) != len(startupMilestoneOrder) {
174	184		return
175	185		}
176		-
177		-	st.mu.Lock()
178		-	defer st.mu.Unlock()
179		-
180		-	if st.finished {
181		-	return
182		-	}
183		-	st.finished = true
184		-
185		-	if st.logger == nil {
186		-	return
187		-	}
188		-
189		-	// Build summary string
190		-	total := time.Since(st.t0)
191		-	var parts []string
192		-	for _, m := range st.milestones {
193		-	parts = append(parts, fmt.Sprintf("%s:%d", m.Name, m.Elapsed.Milliseconds()))
194		-	}
195		-	summary := strings.Join(parts, ",")
196		-
	186	+	st.summaryEmitted = true
197	187		st.logger.Info().
198		-	Int64("total_ms", total.Milliseconds()).
199		-	Str("milestones", summary).
200		-	Msg("startup_trace: cold start complete")
	188	+	Str("backend", st.backend).
	189	+	Str("incomplete_reason", st.incompleteReason).
	190	+	Int64("total_ms", st.milestones[len(st.milestones)-1].Elapsed.Milliseconds()).
	191	+	Interface("milestones", st.milestones).
	192	+	Msg("startup_trace: first presentation")
201	193		}
202	194
203		-	// Enabled returns whether the trace is active.
204		-	func (st *StartupTrace) Enabled() bool {
205		-	if st == nil {
206		-	return false
207		-	}
208		-	return st.enabled
209		-	}
	195	+	// Finish is retained as a harmless compatibility no-op. The only valid source
	196	+	// for first_gtk_presentation is the upstream GTK frame-clock after-paint hook.
	197	+	func (*StartupTrace) Finish() {}
	198	+
	199	+	func (st *StartupTrace) Enabled() bool { return st != nil && st.now != nil }
210	200
211		-	// TotalElapsed returns the total time since T0.
212	201		func (st *StartupTrace) TotalElapsed() time.Duration {
213		-	if st == nil \|\| !st.enabled {
	202	+	if st == nil \|\| st.now == nil {
214	203		return 0
215	204		}
216		-
217	205		st.mu.Lock()
218	206		defer st.mu.Unlock()
219		-	return time.Since(st.t0)
	207	+	return st.now().Sub(st.t0)
220	208		}

@@ -1,32 +1,44 @@
1		package logging	1		package logging
2			2
3		import (	3		import (
4	-	"fmt"
5	-	"strings"
6		"sync"	4		"sync"
7		"time"	5		"time"
8			6
9		"github.com/rs/zerolog"	7		"github.com/rs/zerolog"
10		)	8		)
11			9
12	-	// StartupTrace tracks cold start milestones from process launch to first paint.	10	+	// StartupTrace records the single truthful path from process entry to the first
13	-	// Thread-safe for use across goroutines.	11	+	// GTK presentation. It deliberately rejects unknown, duplicate, and out of
14	-	// Enabled only when log level is debug or trace.	12	+	// order milestones: accepting a convenient timestamp would make the result
			13	+	// unsuitable for cold-start measurement.
15		type StartupTrace struct {	14		type StartupTrace struct {
16	-	mu sync.Mutex	15	+	mu sync.Mutex
17	-	t0 time.Time	16	+	now func() time.Time
18	-	milestones []Milestone	17	+	t0 time.Time
19	-	enabled bool	18	+	milestones []Milestone
20	-	logger *zerolog.Logger	19	+	logger *zerolog.Logger
21	-	buffered []Milestone // milestones recorded before logger is set	20	+	buffered []Milestone
22	-	finished bool	21	+	backend string
			22	+	incompleteReason string
			23	+	summaryEmitted bool
23		}	24		}
24			25
25	-	// Milestone represents a timing checkpoint during startup.	26	+	// Milestone represents a timing checkpoint measured from process entry.
26		type Milestone struct {	27		type Milestone struct {
27		Name string	28		Name string
28	-	Elapsed time.Duration // time since t0	29	+	Elapsed time.Duration
29	-	Delta time.Duration // time since previous milestone	30	+	Delta time.Duration
			31	+	}
			32	+
			33	+	var startupMilestoneOrder = []string{
			34	+	"process_entry",
			35	+	"config_complete",
			36	+	"cef_library_load_begin",
			37	+	"cef_initialized",
			38	+	"browser_create_requested",
			39	+	"first_accelerated_paint_received",
			40	+	"first_dmabuf_texture_swap",
			41	+	"first_gtk_presentation",
30		}	42		}
31			43
32		var (	44		var (

@@ -35,186 +47,162 @@ var (
35		globalTraceOnce sync.Once	47		globalTraceOnce sync.Once
36		)	48		)
37			49
38	-	// InitStartupTrace initializes the global startup trace.	50	+	func newStartupTrace(now func() time.Time) *StartupTrace {
39	-	// Call this as early as possible in main() to capture T0.	51	+	start := now()
40	-	// The trace is enabled only if the given log level is debug or trace.	52	+	return &StartupTrace{
41	-	func InitStartupTrace(logLevel string) {	53	+	now: now,
			54	+	t0: start,
			55	+	milestones: make([]Milestone, 0, len(startupMilestoneOrder)),
			56	+	buffered: make([]Milestone, 0, len(startupMilestoneOrder)),
			57	+	}
			58	+	}
			59	+
			60	+	// InitStartupTrace must be called at the first instruction in main. logLevel is
			61	+	// retained for source compatibility; this measurement is always collected so
			62	+	// its final structured summary is available at normal log level.
			63	+	func InitStartupTrace(_ string) {
42		globalTraceOnce.Do(func() {	64		globalTraceOnce.Do(func() {
43	-	enabled := logLevel == "debug" \|\| logLevel == "trace"	65	+	trace := newStartupTrace(time.Now)
44		globalTraceMu.Lock()	66		globalTraceMu.Lock()
45	-	globalTrace = &StartupTrace{	67	+	globalTrace = trace
46	-	t0: time.Now(),
47	-	milestones: make([]Milestone, 0, 32),
48	-	enabled: enabled,
49	-	buffered: make([]Milestone, 0, 8),
50	-	}
51		globalTraceMu.Unlock()	68		globalTraceMu.Unlock()
52	-
53	-	if enabled {
54	-	// Record process_start as first milestone
55	-	globalTrace.Mark("process_start")
56	-	}
57		})	69		})
58		}	70		}
59			71
60	-	// Trace returns the global startup trace instance.	72	+	// Trace returns the process startup trace. Callers before initialization get a
61	-	// Returns a no-op trace if not initialized or disabled.	73	+	// harmless trace which rejects all transitions.
62		func Trace() *StartupTrace {	74		func Trace() *StartupTrace {
63		globalTraceMu.Lock()	75		globalTraceMu.Lock()
64		defer globalTraceMu.Unlock()	76		defer globalTraceMu.Unlock()
65		if globalTrace == nil {	77		if globalTrace == nil {
66	-	// Return a disabled no-op trace	78	+	return &StartupTrace{}
67	-	return &StartupTrace{enabled: false}
68		}	79		}
69		return globalTrace	80		return globalTrace
70		}	81		}
71			82
72	-	// SetLogger sets the logger for emitting milestone logs.	83	+	// SetLogger makes buffered milestones available to the process logger.
73	-	// Flushes any buffered milestones that were recorded before the logger was set.
74		func (st StartupTrace) SetLogger(logger zerolog.Logger) {	84		func (st StartupTrace) SetLogger(logger zerolog.Logger) {
75	-	if st == nil \|\| !st.enabled {	85	+	if st == nil \|\| logger == nil {
76		return	86		return
77		}	87		}
78	-
79		st.mu.Lock()	88		st.mu.Lock()
80		defer st.mu.Unlock()	89		defer st.mu.Unlock()
81	-
82		st.logger = logger	90		st.logger = logger
83	-		91	+	for _, milestone := range st.buffered {
84	-	// Flush buffered milestones	92	+	st.emitMilestone(milestone)
85	-	for _, m := range st.buffered {
86	-	st.emitMilestone(m)
87		}	93		}
88		st.buffered = nil	94		st.buffered = nil
			95	+	st.emitSummaryLocked()
89		}	96		}
90			97
91	-	// UpdateLogger updates the logger and re-emits all milestones to the new logger.	98	+	// UpdateLogger switches the destination without replaying events. Replaying
92	-	// Call this after the session file logger is available to capture milestones in the log file.	99	+	// would violate the one-shot property in session logs.
93	-	func (st StartupTrace) UpdateLogger(logger zerolog.Logger) {	100	+	func (st StartupTrace) UpdateLogger(logger zerolog.Logger) { st.SetLogger(logger) }
94	-	if st == nil \|\| !st.enabled {	101	+
			102	+	// SetBackend records the selected presentation backend for the final summary.
			103	+	func (st *StartupTrace) SetBackend(backend string) {
			104	+	if st == nil {
95		return	105		return
96		}	106		}
97	-
98		st.mu.Lock()	107		st.mu.Lock()
99		defer st.mu.Unlock()	108		defer st.mu.Unlock()
100	-		109	+	st.backend = backend
101	-	st.logger = logger
102	-
103	-	// Re-emit all milestones to the new logger
104	-	for _, m := range st.milestones {
105	-	st.emitMilestone(m)
106	-	}
107		}	110		}
108			111
109	-	// Mark records a milestone with the given name.	112	+	// SetIncompleteReason records why a trace cannot reach a valid DMABUF result.
110	-	// Emits a debug log line showing elapsed time and delta from previous milestone.	113	+	func (st *StartupTrace) SetIncompleteReason(reason string) {
111	-	func (st *StartupTrace) Mark(name string) {	114	+	if st == nil {
112	-	if st == nil \|\| !st.enabled {
113		return	115		return
114		}	116		}
115	-
116		st.mu.Lock()	117		st.mu.Lock()
117		defer st.mu.Unlock()	118		defer st.mu.Unlock()
			119	+	if st.incompleteReason == "" {
			120	+	st.incompleteReason = reason
			121	+	}
			122	+	}
118			123
119	-	if st.finished {	124	+	// Mark accepts exactly the next non-presentation startup milestone and returns
120	-	return	125	+	// whether it was recorded. first_gtk_presentation is reserved for the GTK
			126	+	// frame-clock after-paint hook through MarkGTKAfterPaint.
			127	+	func (st *StartupTrace) Mark(name string) bool {
			128	+	if name == "first_gtk_presentation" {
			129	+	return false
121		}	130		}
			131	+	return st.mark(name)
			132	+	}
122			133
123	-	now := time.Now()	134	+	// MarkGTKAfterPaint records the final milestone. It is called only from the
124	-	elapsed := now.Sub(st.t0)	135	+	// upstream CEF-to-GTK bridge's first frame-clock after-paint callback.
			136	+	func (st *StartupTrace) MarkGTKAfterPaint() bool {
			137	+	return st.mark("first_gtk_presentation")
			138	+	}
125			139
126	-	var delta time.Duration	140	+	// mark accepts the next milestone and is safe for callbacks from CEF and GTK
127	-	if len(st.milestones) > 0 {	141	+	// threads.
128	-	delta = elapsed - st.milestones[len(st.milestones)-1].Elapsed	142	+	func (st *StartupTrace) mark(name string) bool {
			143	+	if st == nil \|\| st.now == nil {
			144	+	return false
129		}	145		}
130	-		146	+	st.mu.Lock()
131	-	m := Milestone{	147	+	defer st.mu.Unlock()
132	-	Name: name,	148	+	if len(st.milestones) >= len(startupMilestoneOrder) \|\| name != startupMilestoneOrder[len(st.milestones)] {
133	-	Elapsed: elapsed,	149	+	return false
134	-	Delta: delta,
135		}	150		}
136	-	st.milestones = append(st.milestones, m)
137			151
138	-	if st.logger != nil {	152	+	now := st.now()
139	-	st.emitMilestone(m)	153	+	milestone := Milestone{Name: name, Elapsed: now.Sub(st.t0)}
			154	+	// Published fields are integer milliseconds. Compute delta on that same
			155	+	// scale so delta_ms always exactly reconstructs t_ms in collected evidence.
			156	+	previousMilliseconds := int64(0)
			157	+	if len(st.milestones) > 0 {
			158	+	previousMilliseconds = st.milestones[len(st.milestones)-1].Elapsed.Milliseconds()
			159	+	}
			160	+	milestone.Delta = time.Duration(milestone.Elapsed.Milliseconds()-previousMilliseconds) * time.Millisecond
			161	+	st.milestones = append(st.milestones, milestone)
			162	+	if st.logger == nil {
			163	+	st.buffered = append(st.buffered, milestone)
140		} else {	164		} else {
141	-	// Buffer until logger is set	165	+	st.emitMilestone(milestone)
142	-	st.buffered = append(st.buffered, m)
143		}	166		}
			167	+	st.emitSummaryLocked()
			168	+	return true
144		}	169		}
145			170
146	-	// emitMilestone logs a single milestone. Caller must hold mutex.
147		func (st *StartupTrace) emitMilestone(m Milestone) {	171		func (st *StartupTrace) emitMilestone(m Milestone) {
148		if st.logger == nil {	172		if st.logger == nil {
149		return	173		return
150		}	174		}
151	-		175	+	st.logger.Debug().
152	-	elapsedMs := m.Elapsed.Milliseconds()
153	-
154	-	event := st.logger.Debug().
155		Str("milestone", m.Name).	176		Str("milestone", m.Name).
156	-	Int64("t_ms", elapsedMs)	177	+	Int64("t_ms", m.Elapsed.Milliseconds()).
157	-		178	+	Int64("delta_ms", m.Delta.Milliseconds()).
158	-	if m.Delta > 0 {	179	+	Msg("startup_trace: milestone")
159	-	event = event.Int64("delta_ms", m.Delta.Milliseconds())
160	-	}
161	-
162	-	// Format: startup_trace: milestone_name (T+123ms, +45ms)
163	-	if m.Delta > 0 {
164	-	event.Msgf("startup_trace: %s (T+%dms, +%dms)", m.Name, elapsedMs, m.Delta.Milliseconds())
165	-	} else {
166	-	event.Msgf("startup_trace: %s (T+%dms)", m.Name, elapsedMs)
167	-	}
168		}	180		}
169			181
170	-	// Finish marks the startup trace as complete and emits a summary.	182	+	func (st *StartupTrace) emitSummaryLocked() {
171	-	// Called on first_paint milestone.	183	+	if st.summaryEmitted \|\| st.logger == nil \|\| len(st.milestones) != len(startupMilestoneOrder) {
172	-	func (st *StartupTrace) Finish() {
173	-	if st == nil \|\| !st.enabled {
174		return	184		return
175		}	185		}
176	-		186	+	st.summaryEmitted = true
177	-	st.mu.Lock()
178	-	defer st.mu.Unlock()
179	-
180	-	if st.finished {
181	-	return
182	-	}
183	-	st.finished = true
184	-
185	-	if st.logger == nil {
186	-	return
187	-	}
188	-
189	-	// Build summary string
190	-	total := time.Since(st.t0)
191	-	var parts []string
192	-	for _, m := range st.milestones {
193	-	parts = append(parts, fmt.Sprintf("%s:%d", m.Name, m.Elapsed.Milliseconds()))
194	-	}
195	-	summary := strings.Join(parts, ",")
196	-
197		st.logger.Info().	187		st.logger.Info().
198	-	Int64("total_ms", total.Milliseconds()).	188	+	Str("backend", st.backend).
199	-	Str("milestones", summary).	189	+	Str("incomplete_reason", st.incompleteReason).
200	-	Msg("startup_trace: cold start complete")	190	+	Int64("total_ms", st.milestones[len(st.milestones)-1].Elapsed.Milliseconds()).
			191	+	Interface("milestones", st.milestones).
			192	+	Msg("startup_trace: first presentation")
201		}	193		}
202			194
203	-	// Enabled returns whether the trace is active.	195	+	// Finish is retained as a harmless compatibility no-op. The only valid source
204	-	func (st *StartupTrace) Enabled() bool {	196	+	// for first_gtk_presentation is the upstream GTK frame-clock after-paint hook.
205	-	if st == nil {	197	+	func (*StartupTrace) Finish() {}
206	-	return false	198	+
207	-	}	199	+	func (st *StartupTrace) Enabled() bool { return st != nil && st.now != nil }
208	-	return st.enabled
209	-	}
210			200
211	-	// TotalElapsed returns the total time since T0.
212		func (st *StartupTrace) TotalElapsed() time.Duration {	201		func (st *StartupTrace) TotalElapsed() time.Duration {
213	-	if st == nil \|\| !st.enabled {	202	+	if st == nil \|\| st.now == nil {
214		return 0	203		return 0
215		}	204		}
216	-
217		st.mu.Lock()	205		st.mu.Lock()
218		defer st.mu.Unlock()	206		defer st.mu.Unlock()
219	-	return time.Since(st.t0)	207	+	return st.now().Sub(st.t0)
220		}	208		}

A internal/logging/startup_trace_test.go +89 -0

@@ -0,0 +1,89 @@
	1	+	package logging
	2	+
	3	+	import (
	4	+	"bytes"
	5	+	"testing"
	6	+	"time"
	7	+
	8	+	"github.com/rs/zerolog"
	9	+	"github.com/stretchr/testify/require"
	10	+	)
	11	+
	12	+	func TestStartupTraceAcceptsOnlyOrderedOneShotMilestones(t *testing.T) {
	13	+	now := time.Unix(100, 0)
	14	+	trace := newStartupTrace(func() time.Time { return now })
	15	+
	16	+	require.True(t, trace.Mark("process_entry"))
	17	+	require.False(t, trace.Mark("cef_initialized"), "out-of-order transition must be rejected")
	18	+	require.False(t, trace.Mark("process_entry"), "duplicate transition must be rejected")
	19	+
	20	+	for _, name := range []string{
	21	+	"config_complete",
	22	+	"cef_library_load_begin",
	23	+	"cef_initialized",
	24	+	"browser_create_requested",
	25	+	"first_accelerated_paint_received",
	26	+	"first_dmabuf_texture_swap",
	27	+	"first_gtk_presentation",
	28	+	} {
	29	+	now = now.Add(time.Millisecond)
	30	+	if name == "first_gtk_presentation" {
	31	+	require.Truef(t, trace.MarkGTKAfterPaint(), "milestone %s should be accepted", name)
	32	+	} else {
	33	+	require.Truef(t, trace.Mark(name), "milestone %s should be accepted", name)
	34	+	}
	35	+	}
	36	+	require.False(t, trace.Mark("first_gtk_presentation"))
	37	+	}
	38	+
	39	+	func TestStartupTraceQuantizesDeltaToPublishedMilliseconds(t *testing.T) {
	40	+	now := time.Unix(100, 0)
	41	+	trace := newStartupTrace(func() time.Time { return now })
	42	+
	43	+	now = now.Add(1500 * time.Microsecond)
	44	+	require.True(t, trace.Mark("process_entry"))
	45	+	now = now.Add(900 * time.Microsecond)
	46	+	require.True(t, trace.Mark("config_complete"))
	47	+
	48	+	require.Equal(t, int64(1), trace.milestones[0].Elapsed.Milliseconds())
	49	+	require.Equal(t, int64(1), trace.milestones[0].Delta.Milliseconds())
	50	+	require.Equal(t, int64(2), trace.milestones[1].Elapsed.Milliseconds())
	51	+	require.Equal(t, int64(1), trace.milestones[1].Delta.Milliseconds())
	52	+	}
	53	+
	54	+	func TestStartupTraceFinishCannotFabricateFirstGTKPresentation(t *testing.T) {
	55	+	now := time.Unix(100, 0)
	56	+	trace := newStartupTrace(func() time.Time { return now })
	57	+
	58	+	for _, name := range startupMilestoneOrder[:len(startupMilestoneOrder)-1] {
	59	+	now = now.Add(time.Millisecond)
	60	+	require.True(t, trace.Mark(name))
	61	+	}
	62	+
	63	+	trace.Finish() // Legacy callers do not observe the upstream GTK after-paint.
	64	+	require.Len(t, trace.milestones, len(startupMilestoneOrder)-1)
	65	+	require.False(t, trace.Mark("first_gtk_presentation"), "generic callers cannot record the reserved milestone")
	66	+	require.False(t, trace.summaryEmitted)
	67	+	require.True(t, trace.MarkGTKAfterPaint(), "only the after-paint hook may record this milestone")
	68	+	}
	69	+
	70	+	func TestStartupTraceEmitsOneNormalSummaryAtFirstPresentation(t *testing.T) {
	71	+	var output bytes.Buffer
	72	+	logger := zerolog.New(&output)
	73	+	now := time.Unix(100, 0)
	74	+	trace := newStartupTrace(func() time.Time { return now })
	75	+	trace.SetBackend("gdk-dmabuf")
	76	+	trace.SetLogger(&logger)
	77	+
	78	+	for _, name := range startupMilestoneOrder[:len(startupMilestoneOrder)-1] {
	79	+	now = now.Add(time.Millisecond)
	80	+	require.True(t, trace.Mark(name))
	81	+	}
	82	+	now = now.Add(time.Millisecond)
	83	+	require.True(t, trace.MarkGTKAfterPaint())
	84	+	trace.MarkGTKAfterPaint()
	85	+
	86	+	require.Contains(t, output.String(), `"message":"startup_trace: first presentation"`)
	87	+	require.Contains(t, output.String(), `"backend":"gdk-dmabuf"`)
	88	+	require.Equal(t, 1, bytes.Count(output.Bytes(), []byte(`"message":"startup_trace: first presentation"`)))
	89	+	}

@@ -0,0 +1,89 @@
	1	+	package logging
	2	+
	3	+	import (
	4	+	"bytes"
	5	+	"testing"
	6	+	"time"
	7	+
	8	+	"github.com/rs/zerolog"
	9	+	"github.com/stretchr/testify/require"
	10	+	)
	11	+
	12	+	func TestStartupTraceAcceptsOnlyOrderedOneShotMilestones(t *testing.T) {
	13	+	now := time.Unix(100, 0)
	14	+	trace := newStartupTrace(func() time.Time { return now })
	15	+
	16	+	require.True(t, trace.Mark("process_entry"))
	17	+	require.False(t, trace.Mark("cef_initialized"), "out-of-order transition must be rejected")
	18	+	require.False(t, trace.Mark("process_entry"), "duplicate transition must be rejected")
	19	+
	20	+	for _, name := range []string{
	21	+	"config_complete",
	22	+	"cef_library_load_begin",
	23	+	"cef_initialized",
	24	+	"browser_create_requested",
	25	+	"first_accelerated_paint_received",
	26	+	"first_dmabuf_texture_swap",
	27	+	"first_gtk_presentation",
	28	+	} {
	29	+	now = now.Add(time.Millisecond)
	30	+	if name == "first_gtk_presentation" {
	31	+	require.Truef(t, trace.MarkGTKAfterPaint(), "milestone %s should be accepted", name)
	32	+	} else {
	33	+	require.Truef(t, trace.Mark(name), "milestone %s should be accepted", name)
	34	+	}
	35	+	}
	36	+	require.False(t, trace.Mark("first_gtk_presentation"))
	37	+	}
	38	+
	39	+	func TestStartupTraceQuantizesDeltaToPublishedMilliseconds(t *testing.T) {
	40	+	now := time.Unix(100, 0)
	41	+	trace := newStartupTrace(func() time.Time { return now })
	42	+
	43	+	now = now.Add(1500 * time.Microsecond)
	44	+	require.True(t, trace.Mark("process_entry"))
	45	+	now = now.Add(900 * time.Microsecond)
	46	+	require.True(t, trace.Mark("config_complete"))
	47	+
	48	+	require.Equal(t, int64(1), trace.milestones[0].Elapsed.Milliseconds())
	49	+	require.Equal(t, int64(1), trace.milestones[0].Delta.Milliseconds())
	50	+	require.Equal(t, int64(2), trace.milestones[1].Elapsed.Milliseconds())
	51	+	require.Equal(t, int64(1), trace.milestones[1].Delta.Milliseconds())
	52	+	}
	53	+
	54	+	func TestStartupTraceFinishCannotFabricateFirstGTKPresentation(t *testing.T) {
	55	+	now := time.Unix(100, 0)
	56	+	trace := newStartupTrace(func() time.Time { return now })
	57	+
	58	+	for _, name := range startupMilestoneOrder[:len(startupMilestoneOrder)-1] {
	59	+	now = now.Add(time.Millisecond)
	60	+	require.True(t, trace.Mark(name))
	61	+	}
	62	+
	63	+	trace.Finish() // Legacy callers do not observe the upstream GTK after-paint.
	64	+	require.Len(t, trace.milestones, len(startupMilestoneOrder)-1)
	65	+	require.False(t, trace.Mark("first_gtk_presentation"), "generic callers cannot record the reserved milestone")
	66	+	require.False(t, trace.summaryEmitted)
	67	+	require.True(t, trace.MarkGTKAfterPaint(), "only the after-paint hook may record this milestone")
	68	+	}
	69	+
	70	+	func TestStartupTraceEmitsOneNormalSummaryAtFirstPresentation(t *testing.T) {
	71	+	var output bytes.Buffer
	72	+	logger := zerolog.New(&output)
	73	+	now := time.Unix(100, 0)
	74	+	trace := newStartupTrace(func() time.Time { return now })
	75	+	trace.SetBackend("gdk-dmabuf")
	76	+	trace.SetLogger(&logger)
	77	+
	78	+	for _, name := range startupMilestoneOrder[:len(startupMilestoneOrder)-1] {
	79	+	now = now.Add(time.Millisecond)
	80	+	require.True(t, trace.Mark(name))
	81	+	}
	82	+	now = now.Add(time.Millisecond)
	83	+	require.True(t, trace.MarkGTKAfterPaint())
	84	+	trace.MarkGTKAfterPaint()
	85	+
	86	+	require.Contains(t, output.String(), `"message":"startup_trace: first presentation"`)
	87	+	require.Contains(t, output.String(), `"backend":"gdk-dmabuf"`)
	88	+	require.Equal(t, 1, bytes.Count(output.Bytes(), []byte(`"message":"startup_trace: first presentation"`)))
	89	+	}

M internal/ui/coordinator/content/navigation.go +0 -4


@@ -288,10 +288,6 @@ func (c *Coordinator) revealIfPending(ctx context.Context, paneID entity.PaneID,
288	288		}
289	289		}
290	290
291		-	// Mark first_paint and finish startup trace
292		-	logging.Trace().Mark("first_paint")
293		-	logging.Trace().Finish()
294		-
295	291		if c.onWebViewShown != nil {
296	292		c.onWebViewShown(paneID)
297	293		}


@@ -288,10 +288,6 @@ func (c *Coordinator) revealIfPending(ctx context.Context, paneID entity.PaneID,
288		}	288	}
289		}	289	}
290			290
291	-	// Mark first_paint and finish startup trace
292	-	logging.Trace().Mark("first_paint")
293	-	logging.Trace().Finish()
294	-
295		if c.onWebViewShown != nil {	291	if c.onWebViewShown != nil {
296		c.onWebViewShown(paneID)	292	c.onWebViewShown(paneID)
297		}	293	}

A scripts/collect_first_presentation.sh +176 -0

@@ -0,0 +1,176 @@
	1	+	#!/usr/bin/env bash
	2	+	# Collect exactly five isolated CEF/DMABUF cold starts. The application is
	3	+	# deliberately terminated after the bounded observation window; a completed
	4	+	# first-presentation summary, rather than process exit, is the success signal.
	5	+	set -euo pipefail
	6	+
	7	+	readonly runs=5
	8	+	readonly timeout_seconds="${DUMBER_FIRST_PRESENTATION_TIMEOUT_SECONDS:-45}"
	9	+	readonly runtime="${DUMBER_CEF_DIR:-$HOME/.local/share/cef-147-runtime}"
	10	+	readonly binary="${DUMBER_FIRST_PRESENTATION_BIN:-$PWD/dist/dumber}"
	11	+
	12	+	fail_unsafe_output() {
	13	+	echo "first-presentation: unsafe output path: $1" >&2
	14	+	exit 2
	15	+	}
	16	+
	17	+	if [[ -v DUMBER_FIRST_PRESENTATION_OUTPUT ]]; then
	18	+	output="$DUMBER_FIRST_PRESENTATION_OUTPUT"
	19	+	else
	20	+	# Evidence is state, not source: keep the default outside the checkout and
	21	+	# make every invocation a fresh child of the external evidence directory.
	22	+	readonly state_home="${XDG_STATE_HOME:-$HOME/.local/state}"
	23	+	[[ "$state_home" == /* ]] \|\| fail_unsafe_output "XDG_STATE_HOME must be absolute"
	24	+	readonly evidence_root="$state_home/dumber/roadmap-evidence"
	25	+	mkdir -p -- "$evidence_root" \|\| fail_unsafe_output "could not create XDG state directory"
	26	+	canonical_evidence_root="$(realpath -e -- "$evidence_root")" \|\| \
	27	+	fail_unsafe_output "XDG state directory cannot be canonicalized"
	28	+	[[ "$canonical_evidence_root" == "$evidence_root" && ! -L "$evidence_root" ]] \|\| \
	29	+	fail_unsafe_output "XDG state directory must not contain symbolic links"
	30	+	output="$evidence_root/first-presentation-$(date -u +%Y%m%dT%H%M%S)-$$"
	31	+	fi
	32	+	readonly output
	33	+	readonly upstream_module="github.com/bnema/purego-cef2gtk"
	34	+	readonly upstream_tag="v0.8.4"
	35	+	readonly upstream_revision="f217ece342dea3ef2a3f98671fcd16a39ad0037d"
	36	+
	37	+	# The artifact destination is caller-controlled. Never empty or recursively
	38	+	# clear it: collection only writes to a newly-created directory whose parent is
	39	+	# already canonical and contains no symbolic-link hop.
	40	+	prepare_output() {
	41	+	local parent name canonical_parent canonical_output
	42	+
	43	+	[[ -n "$output" ]] \|\| fail_unsafe_output "path must not be empty"
	44	+	[[ "$output" == /* ]] \|\| fail_unsafe_output "path must be absolute"
	45	+	[[ "$output" != "/" ]] \|\| fail_unsafe_output "path must not be /"
	46	+	[[ "${output%/}" != "${HOME%/}" ]] \|\| fail_unsafe_output "path must not be HOME"
	47	+	[[ "$output" != .. && "$output" != ../* && "$output" != /.. && "$output" != /../* ]] \|\| \
	48	+	fail_unsafe_output "path must not contain parent traversal"
	49	+	[[ ! -e "$output" && ! -L "$output" ]] \|\| fail_unsafe_output "path must be a fresh directory"
	50	+
	51	+	parent="$(dirname -- "$output")"
	52	+	name="$(basename -- "$output")"
	53	+	[[ -n "$name" && "$name" != "." && "$name" != ".." ]] \|\| fail_unsafe_output "invalid directory name"
	54	+	[[ -d "$parent" && ! -L "$parent" ]] \|\| fail_unsafe_output "parent must be an existing directory"
	55	+	canonical_parent="$(realpath -e -- "$parent")" \|\| fail_unsafe_output "parent cannot be canonicalized"
	56	+	[[ "$parent" == "$canonical_parent" ]] \|\| fail_unsafe_output "parent must not contain symbolic links"
	57	+
	58	+	mkdir -- "$output" \|\| fail_unsafe_output "could not create fresh directory"
	59	+	canonical_output="$(realpath -e -- "$output")" \|\| fail_unsafe_output "created directory cannot be canonicalized"
	60	+	[[ -d "$output" && ! -L "$output" && "$canonical_output" == "$canonical_parent/$name" ]] \|\| \
	61	+	fail_unsafe_output "created directory changed unexpectedly"
	62	+	}
	63	+
	64	+	prepare_output
	65	+
	66	+	[[ -x "$binary" ]] \|\| { echo "first-presentation: executable not found: $binary" >&2; exit 2; }
	67	+	[[ -d "$runtime" ]] \|\| { echo "first-presentation: CEF runtime not found: $runtime" >&2; exit 2; }
	68	+	[[ -n "${WAYLAND_DISPLAY:-}${DISPLAY:-}" ]] \|\| { echo "first-presentation: a current Wayland/X11 display is required" >&2; exit 2; }
	69	+	[[ "$(go list -m -f '{{.Version}}' "$upstream_module")" == "$upstream_tag" ]] \|\| {
	70	+	echo "first-presentation: expected $upstream_module@$upstream_tag" >&2
	71	+	exit 2
	72	+	}
	73	+
	74	+	# Raw logs and temporary XDG homes may contain machine-local paths. Keep them
	75	+	# outside the committed artifact directory and always remove them.
	76	+	work_root="$(mktemp -d "${TMPDIR:-/tmp}/dumber-first-presentation.XXXXXX")"
	77	+	readonly work_root
	78	+	cleanup_work_root() {
	79	+	[[ -n "${work_root:-}" && -d "$work_root" && ! -L "$work_root" ]] \|\| return
	80	+	rm -rf -- "$work_root"
	81	+	}
	82	+	trap cleanup_work_root EXIT
	83	+	python3 - "$output/metadata.json" "$binary" "$timeout_seconds" "$upstream_module" "$upstream_tag" "$upstream_revision" <<'PY'
	84	+	import hashlib, json, os, platform, subprocess, sys
	85	+	path, binary, timeout, upstream_module, upstream_tag, upstream_revision = sys.argv[1:]
	86	+	with open(binary, "rb") as candidate:
	87	+	binary_sha256 = hashlib.file_digest(candidate, "sha256").hexdigest()
	88	+
	89	+	# These deliberately coarse labels support comparison without exposing a host,
	90	+	# device name, driver version, path, or environment dump.
	91	+	architecture = {"x86_64": "amd64", "amd64": "amd64", "aarch64": "arm64", "arm64": "arm64"}.get(platform.machine().lower(), "other")
	92	+	os_label = {"linux": "linux", "darwin": "darwin", "windows": "windows"}.get(platform.system().lower(), "other")
	93	+	display_protocol = "wayland" if os.environ.get("WAYLAND_DISPLAY") else "x11"
	94	+	gpu_profile = os.environ.get("DUMBER_MACHINE_GPU_PROFILE", "generic-gpu")
	95	+	allowed_gpu_profiles = {"generic-gpu", "integrated-gpu", "discrete-gpu", "hybrid-gpu", "virtual-gpu", "unknown-gpu"}
	96	+	if gpu_profile not in allowed_gpu_profiles:
	97	+	raise SystemExit("DUMBER_MACHINE_GPU_PROFILE must be a non-identifying profile label")
	98	+
	99	+	json.dump({
	100	+	"runs": 5,
	101	+	"runtime": {"label": "cef", "version": "147"},
	102	+	"binary": {"label": "dumber", "sha256": binary_sha256},
	103	+	"timeout_seconds": int(timeout),
	104	+	"measured_source_revision": subprocess.check_output(["git", "-c", f"safe.directory={os.getcwd()}", "rev-parse", "HEAD"], text=True).strip(),
	105	+	"upstream": {"module": upstream_module, "tag": upstream_tag, "revision": upstream_revision},
	106	+	"comparison": {"os": os_label, "architecture": architecture, "display_protocol": display_protocol, "machine_gpu_profile": gpu_profile},
	107	+	"render_configuration": {"backend": "gdk-dmabuf", "buffer_sharing": "dmabuf", "renderer": "vulkan"}
	108	+	}, open(path, "w"), indent=2, sort_keys=True)
	109	+	PY
	110	+
	111	+	for number in $(seq 1 "$runs"); do
	112	+	run="$(printf 'run-%02d' "$number")"
	113	+	root="$work_root/$run"
	114	+	mkdir -p "$root"/{config,data,state,cache}
	115	+	mkdir -p "$root/config/dumber"
	116	+	cat >"$root/config/dumber/config.toml" <<EOF
	117	+	[logging]
	118	+	level = "debug"
	119	+	format = "json"
	120	+	enable_file_log = false
	121	+
	122	+	[engine.cef]
	123	+	cef_dir = "$runtime"
	124	+	EOF
	125	+	# Every directory below is newly created for this one launch. Do not inherit
	126	+	# a profile, shader cache, CEF root cache, or mutable app configuration.
	127	+	set +e
	128	+	env -i \
	129	+	HOME="$HOME" PATH="$PATH" LANG="${LANG:-C.UTF-8}" \
	130	+	WAYLAND_DISPLAY="${WAYLAND_DISPLAY:-}" DISPLAY="${DISPLAY:-}" XDG_RUNTIME_DIR="${XDG_RUNTIME_DIR:-}" \
	131	+	DBUS_SESSION_BUS_ADDRESS="${DBUS_SESSION_BUS_ADDRESS:-}" XAUTHORITY="${XAUTHORITY:-}" \
	132	+	XDG_CONFIG_HOME="$root/config" XDG_DATA_HOME="$root/data" XDG_STATE_HOME="$root/state" XDG_CACHE_HOME="$root/cache" \
	133	+	DUMBER_CEF_ROOT_CACHE_PATH="$root/cef-root-cache" DUMBER_RENDER_STACK="vulkan-dmabuf" \
	134	+	PUREGO_CEF2GTK_BACKEND="gdk-dmabuf" PUREGO_CEF2GTK_ANGLE_BACKEND="vulkan" GSK_RENDERER="vulkan" \
	135	+	timeout --signal=TERM --kill-after=5s "${timeout_seconds}s" "$binary" browse about:blank >"$root/process.log" 2>&1
	136	+	set -e
	137	+	# A completed, valid first-presentation summary is the observation success
	138	+	# signal. The GUI may later be stopped by timeout or terminate independently.
	139	+	python3 - "$root/process.log" "$output/$run.json" "$run" <<'PY'
	140	+	import json, sys
	141	+	log, destination, run = sys.argv[1:]
	142	+	order = ["process_entry", "config_complete", "cef_library_load_begin", "cef_initialized", "browser_create_requested", "first_accelerated_paint_received", "first_dmabuf_texture_swap", "first_gtk_presentation"]
	143	+	records, summary = [], None
	144	+	for line in open(log, errors="replace"):
	145	+	try: event = json.loads(line)
	146	+	except json.JSONDecodeError: continue
	147	+	if event.get("message") == "startup_trace: milestone":
	148	+	records.append({key: event.get(key) for key in ("milestone", "t_ms", "delta_ms")})
	149	+	if event.get("message") == "startup_trace: first presentation":
	150	+	summary = {key: event.get(key) for key in ("backend", "incomplete_reason", "total_ms")}
	151	+	names = [event.get("milestone") for event in records]
	152	+	times = [event.get("t_ms") for event in records]
	153	+	deltas = [event.get("delta_ms") for event in records]
	154	+	valid = names == order and all(type(t) is int for t in times) and times == sorted(times)
	155	+	valid = valid and all(type(delta) is int for delta in deltas)
	156	+	valid = valid and all(delta == current - previous for previous, current, delta in zip([0] + times, times, deltas))
	157	+	valid = valid and summary is not None and summary.get("backend") == "gdk-dmabuf" and not summary.get("incomplete_reason")
	158	+	valid = valid and type(summary.get("total_ms")) is int and summary["total_ms"] == times[-1]
	159	+	result = {"run": run, "valid": valid, "milestones": records, "summary": summary}
	160	+	json.dump(result, open(destination, "w"), indent=2)
	161	+	if not valid:
	162	+	raise SystemExit(f"{run}: invalid or incomplete non-DMABUF timeline")
	163	+	PY
	164	+	done
	165	+
	166	+	python3 - "$output" <<'PY'
	167	+	import json, math, statistics, sys
	168	+	root = sys.argv[1]
	169	+	runs = [json.load(open(f"{root}/run-{n:02d}.json")) for n in range(1, 6)]
	170	+	if len(runs) != 5 or not all(run["valid"] for run in runs): raise SystemExit("expected exactly five valid runs")
	171	+	totals = sorted(run["summary"]["total_ms"] for run in runs)
	172	+	p95 = totals[max(0, math.ceil(.95 * len(totals)) - 1)]
	173	+	json.dump({"runs": 5, "total_ms": {"min": totals[0], "median": statistics.median(totals), "max": totals[-1], "p95": p95}}, open(f"{root}/baseline.json", "w"), indent=2)
	174	+	PY
	175	+
	176	+	echo "first-presentation artifacts: $output"

@@ -0,0 +1,176 @@
	1	+	#!/usr/bin/env bash
	2	+	# Collect exactly five isolated CEF/DMABUF cold starts. The application is
	3	+	# deliberately terminated after the bounded observation window; a completed
	4	+	# first-presentation summary, rather than process exit, is the success signal.
	5	+	set -euo pipefail
	6	+
	7	+	readonly runs=5
	8	+	readonly timeout_seconds="${DUMBER_FIRST_PRESENTATION_TIMEOUT_SECONDS:-45}"
	9	+	readonly runtime="${DUMBER_CEF_DIR:-$HOME/.local/share/cef-147-runtime}"
	10	+	readonly binary="${DUMBER_FIRST_PRESENTATION_BIN:-$PWD/dist/dumber}"
	11	+
	12	+	fail_unsafe_output() {
	13	+	echo "first-presentation: unsafe output path: $1" >&2
	14	+	exit 2
	15	+	}
	16	+
	17	+	if [[ -v DUMBER_FIRST_PRESENTATION_OUTPUT ]]; then
	18	+	output="$DUMBER_FIRST_PRESENTATION_OUTPUT"
	19	+	else
	20	+	# Evidence is state, not source: keep the default outside the checkout and
	21	+	# make every invocation a fresh child of the external evidence directory.
	22	+	readonly state_home="${XDG_STATE_HOME:-$HOME/.local/state}"
	23	+	[[ "$state_home" == /* ]] \|\| fail_unsafe_output "XDG_STATE_HOME must be absolute"
	24	+	readonly evidence_root="$state_home/dumber/roadmap-evidence"
	25	+	mkdir -p -- "$evidence_root" \|\| fail_unsafe_output "could not create XDG state directory"
	26	+	canonical_evidence_root="$(realpath -e -- "$evidence_root")" \|\| \
	27	+	fail_unsafe_output "XDG state directory cannot be canonicalized"
	28	+	[[ "$canonical_evidence_root" == "$evidence_root" && ! -L "$evidence_root" ]] \|\| \
	29	+	fail_unsafe_output "XDG state directory must not contain symbolic links"
	30	+	output="$evidence_root/first-presentation-$(date -u +%Y%m%dT%H%M%S)-$$"
	31	+	fi
	32	+	readonly output
	33	+	readonly upstream_module="github.com/bnema/purego-cef2gtk"
	34	+	readonly upstream_tag="v0.8.4"
	35	+	readonly upstream_revision="f217ece342dea3ef2a3f98671fcd16a39ad0037d"
	36	+
	37	+	# The artifact destination is caller-controlled. Never empty or recursively
	38	+	# clear it: collection only writes to a newly-created directory whose parent is
	39	+	# already canonical and contains no symbolic-link hop.
	40	+	prepare_output() {
	41	+	local parent name canonical_parent canonical_output
	42	+
	43	+	[[ -n "$output" ]] \|\| fail_unsafe_output "path must not be empty"
	44	+	[[ "$output" == /* ]] \|\| fail_unsafe_output "path must be absolute"
	45	+	[[ "$output" != "/" ]] \|\| fail_unsafe_output "path must not be /"
	46	+	[[ "${output%/}" != "${HOME%/}" ]] \|\| fail_unsafe_output "path must not be HOME"
	47	+	[[ "$output" != .. && "$output" != ../* && "$output" != /.. && "$output" != /../* ]] \|\| \
	48	+	fail_unsafe_output "path must not contain parent traversal"
	49	+	[[ ! -e "$output" && ! -L "$output" ]] \|\| fail_unsafe_output "path must be a fresh directory"
	50	+
	51	+	parent="$(dirname -- "$output")"
	52	+	name="$(basename -- "$output")"
	53	+	[[ -n "$name" && "$name" != "." && "$name" != ".." ]] \|\| fail_unsafe_output "invalid directory name"
	54	+	[[ -d "$parent" && ! -L "$parent" ]] \|\| fail_unsafe_output "parent must be an existing directory"
	55	+	canonical_parent="$(realpath -e -- "$parent")" \|\| fail_unsafe_output "parent cannot be canonicalized"
	56	+	[[ "$parent" == "$canonical_parent" ]] \|\| fail_unsafe_output "parent must not contain symbolic links"
	57	+
	58	+	mkdir -- "$output" \|\| fail_unsafe_output "could not create fresh directory"
	59	+	canonical_output="$(realpath -e -- "$output")" \|\| fail_unsafe_output "created directory cannot be canonicalized"
	60	+	[[ -d "$output" && ! -L "$output" && "$canonical_output" == "$canonical_parent/$name" ]] \|\| \
	61	+	fail_unsafe_output "created directory changed unexpectedly"
	62	+	}
	63	+
	64	+	prepare_output
	65	+
	66	+	[[ -x "$binary" ]] \|\| { echo "first-presentation: executable not found: $binary" >&2; exit 2; }
	67	+	[[ -d "$runtime" ]] \|\| { echo "first-presentation: CEF runtime not found: $runtime" >&2; exit 2; }
	68	+	[[ -n "${WAYLAND_DISPLAY:-}${DISPLAY:-}" ]] \|\| { echo "first-presentation: a current Wayland/X11 display is required" >&2; exit 2; }
	69	+	[[ "$(go list -m -f '{{.Version}}' "$upstream_module")" == "$upstream_tag" ]] \|\| {
	70	+	echo "first-presentation: expected $upstream_module@$upstream_tag" >&2
	71	+	exit 2
	72	+	}
	73	+
	74	+	# Raw logs and temporary XDG homes may contain machine-local paths. Keep them
	75	+	# outside the committed artifact directory and always remove them.
	76	+	work_root="$(mktemp -d "${TMPDIR:-/tmp}/dumber-first-presentation.XXXXXX")"
	77	+	readonly work_root
	78	+	cleanup_work_root() {
	79	+	[[ -n "${work_root:-}" && -d "$work_root" && ! -L "$work_root" ]] \|\| return
	80	+	rm -rf -- "$work_root"
	81	+	}
	82	+	trap cleanup_work_root EXIT
	83	+	python3 - "$output/metadata.json" "$binary" "$timeout_seconds" "$upstream_module" "$upstream_tag" "$upstream_revision" <<'PY'
	84	+	import hashlib, json, os, platform, subprocess, sys
	85	+	path, binary, timeout, upstream_module, upstream_tag, upstream_revision = sys.argv[1:]
	86	+	with open(binary, "rb") as candidate:
	87	+	binary_sha256 = hashlib.file_digest(candidate, "sha256").hexdigest()
	88	+
	89	+	# These deliberately coarse labels support comparison without exposing a host,
	90	+	# device name, driver version, path, or environment dump.
	91	+	architecture = {"x86_64": "amd64", "amd64": "amd64", "aarch64": "arm64", "arm64": "arm64"}.get(platform.machine().lower(), "other")
	92	+	os_label = {"linux": "linux", "darwin": "darwin", "windows": "windows"}.get(platform.system().lower(), "other")
	93	+	display_protocol = "wayland" if os.environ.get("WAYLAND_DISPLAY") else "x11"
	94	+	gpu_profile = os.environ.get("DUMBER_MACHINE_GPU_PROFILE", "generic-gpu")
	95	+	allowed_gpu_profiles = {"generic-gpu", "integrated-gpu", "discrete-gpu", "hybrid-gpu", "virtual-gpu", "unknown-gpu"}
	96	+	if gpu_profile not in allowed_gpu_profiles:
	97	+	raise SystemExit("DUMBER_MACHINE_GPU_PROFILE must be a non-identifying profile label")
	98	+
	99	+	json.dump({
	100	+	"runs": 5,
	101	+	"runtime": {"label": "cef", "version": "147"},
	102	+	"binary": {"label": "dumber", "sha256": binary_sha256},
	103	+	"timeout_seconds": int(timeout),
	104	+	"measured_source_revision": subprocess.check_output(["git", "-c", f"safe.directory={os.getcwd()}", "rev-parse", "HEAD"], text=True).strip(),
	105	+	"upstream": {"module": upstream_module, "tag": upstream_tag, "revision": upstream_revision},
	106	+	"comparison": {"os": os_label, "architecture": architecture, "display_protocol": display_protocol, "machine_gpu_profile": gpu_profile},
	107	+	"render_configuration": {"backend": "gdk-dmabuf", "buffer_sharing": "dmabuf", "renderer": "vulkan"}
	108	+	}, open(path, "w"), indent=2, sort_keys=True)
	109	+	PY
	110	+
	111	+	for number in $(seq 1 "$runs"); do
	112	+	run="$(printf 'run-%02d' "$number")"
	113	+	root="$work_root/$run"
	114	+	mkdir -p "$root"/{config,data,state,cache}
	115	+	mkdir -p "$root/config/dumber"
	116	+	cat >"$root/config/dumber/config.toml" <<EOF
	117	+	[logging]
	118	+	level = "debug"
	119	+	format = "json"
	120	+	enable_file_log = false
	121	+
	122	+	[engine.cef]
	123	+	cef_dir = "$runtime"
	124	+	EOF
	125	+	# Every directory below is newly created for this one launch. Do not inherit
	126	+	# a profile, shader cache, CEF root cache, or mutable app configuration.
	127	+	set +e
	128	+	env -i \
	129	+	HOME="$HOME" PATH="$PATH" LANG="${LANG:-C.UTF-8}" \
	130	+	WAYLAND_DISPLAY="${WAYLAND_DISPLAY:-}" DISPLAY="${DISPLAY:-}" XDG_RUNTIME_DIR="${XDG_RUNTIME_DIR:-}" \
	131	+	DBUS_SESSION_BUS_ADDRESS="${DBUS_SESSION_BUS_ADDRESS:-}" XAUTHORITY="${XAUTHORITY:-}" \
	132	+	XDG_CONFIG_HOME="$root/config" XDG_DATA_HOME="$root/data" XDG_STATE_HOME="$root/state" XDG_CACHE_HOME="$root/cache" \
	133	+	DUMBER_CEF_ROOT_CACHE_PATH="$root/cef-root-cache" DUMBER_RENDER_STACK="vulkan-dmabuf" \
	134	+	PUREGO_CEF2GTK_BACKEND="gdk-dmabuf" PUREGO_CEF2GTK_ANGLE_BACKEND="vulkan" GSK_RENDERER="vulkan" \
	135	+	timeout --signal=TERM --kill-after=5s "${timeout_seconds}s" "$binary" browse about:blank >"$root/process.log" 2>&1
	136	+	set -e
	137	+	# A completed, valid first-presentation summary is the observation success
	138	+	# signal. The GUI may later be stopped by timeout or terminate independently.
	139	+	python3 - "$root/process.log" "$output/$run.json" "$run" <<'PY'
	140	+	import json, sys
	141	+	log, destination, run = sys.argv[1:]
	142	+	order = ["process_entry", "config_complete", "cef_library_load_begin", "cef_initialized", "browser_create_requested", "first_accelerated_paint_received", "first_dmabuf_texture_swap", "first_gtk_presentation"]
	143	+	records, summary = [], None
	144	+	for line in open(log, errors="replace"):
	145	+	try: event = json.loads(line)
	146	+	except json.JSONDecodeError: continue
	147	+	if event.get("message") == "startup_trace: milestone":
	148	+	records.append({key: event.get(key) for key in ("milestone", "t_ms", "delta_ms")})
	149	+	if event.get("message") == "startup_trace: first presentation":
	150	+	summary = {key: event.get(key) for key in ("backend", "incomplete_reason", "total_ms")}
	151	+	names = [event.get("milestone") for event in records]
	152	+	times = [event.get("t_ms") for event in records]
	153	+	deltas = [event.get("delta_ms") for event in records]
	154	+	valid = names == order and all(type(t) is int for t in times) and times == sorted(times)
	155	+	valid = valid and all(type(delta) is int for delta in deltas)
	156	+	valid = valid and all(delta == current - previous for previous, current, delta in zip([0] + times, times, deltas))
	157	+	valid = valid and summary is not None and summary.get("backend") == "gdk-dmabuf" and not summary.get("incomplete_reason")
	158	+	valid = valid and type(summary.get("total_ms")) is int and summary["total_ms"] == times[-1]
	159	+	result = {"run": run, "valid": valid, "milestones": records, "summary": summary}
	160	+	json.dump(result, open(destination, "w"), indent=2)
	161	+	if not valid:
	162	+	raise SystemExit(f"{run}: invalid or incomplete non-DMABUF timeline")
	163	+	PY
	164	+	done
	165	+
	166	+	python3 - "$output" <<'PY'
	167	+	import json, math, statistics, sys
	168	+	root = sys.argv[1]
	169	+	runs = [json.load(open(f"{root}/run-{n:02d}.json")) for n in range(1, 6)]
	170	+	if len(runs) != 5 or not all(run["valid"] for run in runs): raise SystemExit("expected exactly five valid runs")
	171	+	totals = sorted(run["summary"]["total_ms"] for run in runs)
	172	+	p95 = totals[max(0, math.ceil(.95 * len(totals)) - 1)]
	173	+	json.dump({"runs": 5, "total_ms": {"min": totals[0], "median": statistics.median(totals), "max": totals[-1], "p95": p95}}, open(f"{root}/baseline.json", "w"), indent=2)
	174	+	PY
	175	+
	176	+	echo "first-presentation artifacts: $output"

M vendor/github.com/bnema/purego-cef2gtk/handlers.go +104 -17 generated file: collapsed

load diff

M vendor/github.com/bnema/purego-cef2gtk/internal/gtkgdk/renderer.go +44 -6 generated file: collapsed

load diff

M vendor/github.com/bnema/purego-cef2gtk/internal/gtkgl/accelerated_renderer.go +6 -0 generated file: collapsed

load diff

M vendor/github.com/bnema/purego-cef2gtk/view.go +207 -2 generated file: collapsed

load diff

M vendor/modules.txt +1 -1 generated file: collapsed

load diff