core(fr): add lighthouseMarker timeOrigin support (#12688)

lighthouse-core/gather/gatherers/trace.js

@@ -12,6 +12,7 @@
  */
 
 const FRGatherer = require('../../fraggle-rock/gather/base-gatherer.js');
+const TraceProcessor = require('../../lib/tracehouse/trace-processor.js');
 
 class Trace extends FRGatherer {
   /** @type {LH.Trace} */
@@ -95,14 +96,19 @@ class Trace extends FRGatherer {
   /**
    * @param {LH.Gatherer.FRTransitionalContext} passContext
    */
-  async startSensitiveInstrumentation({driver}) {
+  async startSensitiveInstrumentation({driver, gatherMode}) {
     // TODO(FR-COMPAT): read additional trace categories from overall settings?
     // TODO(FR-COMPAT): check if CSS/DOM domains have been enabled in another session and warn?
     await driver.defaultSession.sendCommand('Page.enable');
     await driver.defaultSession.sendCommand('Tracing.start', {
       categories: Trace.getDefaultTraceCategories().join(','),
       options: 'sampling-frequency=10000', // 1000 is default and too slow.
     });
+
+    if (gatherMode === 'timespan') {
+      await driver.defaultSession.sendCommand('Tracing.recordClockSyncMarker',
+        {syncId: TraceProcessor.TIMESPAN_MARKER_ID});
+    }
   }
 
   /**

lighthouse-core/lib/tracehouse/trace-processor.js

@@ -17,7 +17,7 @@
  */
 
 /** @typedef {Omit<LH.Artifacts.NavigationTraceTimes, 'firstContentfulPaintAllFrames'|'traceEnd'>} TraceNavigationTimesForFrame */
-/** @typedef {'lastNavigationStart'|'firstResourceSendRequest'} TimeOriginDeterminationMethod */
+/** @typedef {'lastNavigationStart'|'firstResourceSendRequest'|'lighthouseMarker'|'auto'} TimeOriginDeterminationMethod */
 /** @typedef {Omit<LH.TraceEvent, 'name'|'args'> & {name: 'FrameCommittedInBrowser', args: {data: {frame: string, url: string, parent?: string}}}} FrameCommittedEvent */
 /** @typedef {Omit<LH.TraceEvent, 'name'|'args'> & {name: 'largestContentfulPaint::Invalidate'|'largestContentfulPaint::Candidate', args: {data?: {size?: number}, frame: string}}} LCPEvent */
 /** @typedef {Omit<LH.TraceEvent, 'name'|'args'> & {name: 'largestContentfulPaint::Candidate', args: {data: {size: number}, frame: string}}} LCPCandidateEvent */
@@ -39,6 +39,10 @@ const SCHEDULABLE_TASK_TITLE_ALT2 = 'ThreadControllerImpl::DoWork';
 const SCHEDULABLE_TASK_TITLE_ALT3 = 'TaskQueueManager::ProcessTaskFromWorkQueue';
 
 class TraceProcessor {
+  static get TIMESPAN_MARKER_ID() {
+    return '__lighthouseTimespanStart__';
+  }
+
   /**
    * @return {Error}
    */
@@ -67,6 +71,13 @@ class TraceProcessor {
     return new Error('No FirstContentfulPaint event found');
   }
 
+  /**
+   * @return {Error}
+   */
+  static createNoLighthouseMarkerError() {
+    return new Error('No Lighthouse timespan marker event found');
+  }
+
   /**
    * Returns true if the event is a navigation start event of a document whose URL seems valid.
    *
@@ -584,7 +595,7 @@ class TraceProcessor {
    * @return {LH.Artifacts.ProcessedTrace}
   */
   static processTrace(trace, options) {
-    const {timeOriginDeterminationMethod = 'lastNavigationStart'} = options || {};
+    const {timeOriginDeterminationMethod = 'auto'} = options || {};
 
     // Parse the trace for our key events and sort them by timestamp. Note: sort
     // *must* be stable to keep events correctly nested.
@@ -780,6 +791,21 @@ class TraceProcessor {
    * @return {LH.TraceEvent}
    */
   static computeTimeOrigin(traceEventSubsets, method) {
+    const lastNavigationStart = () => {
+      // Our time origin will be the last frame navigation in the trace
+      const frameEvents = traceEventSubsets.frameEvents;
+      return frameEvents.filter(this._isNavigationStartOfInterest).pop();
+    };
+
+    const lighthouseMarker = () => {
+      const frameEvents = traceEventSubsets.keyEvents;
+      return frameEvents.find(
+        evt =>
+          evt.name === 'clock_sync' &&
+          evt.args.sync_id === TraceProcessor.TIMESPAN_MARKER_ID
+      );
+    };
+
     switch (method) {
       case 'firstResourceSendRequest': {
         // Our time origin will be the timestamp of the first request that's sent in the frame.
@@ -792,12 +818,20 @@ class TraceProcessor {
         return fetchStart;
       }
       case 'lastNavigationStart': {
-        // Our time origin will be the last frame navigation in the trace
-        const frameEvents = traceEventSubsets.frameEvents;
-        const navigationStart = frameEvents.filter(this._isNavigationStartOfInterest).pop();
+        const navigationStart = lastNavigationStart();
         if (!navigationStart) throw this.createNoNavstartError();
         return navigationStart;
       }
+      case 'lighthouseMarker': {
+        const marker = lighthouseMarker();
+        if (!marker) throw this.createNoLighthouseMarkerError();
+        return marker;
+      }
+      case 'auto': {
+        const marker = lighthouseMarker() || lastNavigationStart();
+        if (!marker) throw this.createNoNavstartError();
+        return marker;
+      }
     }
   }
 

lighthouse-core/test/fixtures/traces/timespan-trace-m91.json

@@ -0,0 +1,48 @@
+{
+  "traceEvents": [
+    {"args":{"name":"swapper"},"cat":"__metadata","name":"thread_name","ph":"M","pid":98662,"tid":0,"ts":0},
+    {"args":{"name":"StackSamplingProfiler"},"cat":"__metadata","name":"thread_name","ph":"M","pid":98673,"tid":11011,"ts":0},
+    {"args":{"name":"CrBrowserMain"},"cat":"__metadata","name":"thread_name","ph":"M","pid":98662,"tid":775,"ts":0},
+    {"args":{"name":"NetworkService"},"cat":"__metadata","name":"thread_name","ph":"M","pid":98662,"tid":53507,"ts":0},
+    {"args":{"name":"CrRendererMain"},"cat":"__metadata","name":"thread_name","ph":"M","pid":98676,"tid":775,"ts":0},
+    {"args":{"name":"Chrome_DevToolsHandlerThread"},"cat":"__metadata","name":"thread_name","ph":"M","pid":98662,"tid":130819,"ts":0},
+    {"args":{"name":"VizCompositorThread"},"cat":"__metadata","name":"thread_name","ph":"M","pid":98673,"tid":44547,"ts":0},
+    {"args":{"name":"CrGpuMain"},"cat":"__metadata","name":"thread_name","ph":"M","pid":98673,"tid":775,"ts":0},
+    {"args":{"name":"Chrome_ChildIOThread"},"cat":"__metadata","name":"thread_name","ph":"M","pid":98673,"tid":34307,"ts":0},
+    {"args":{"name":"CacheThread_BlockFile"},"cat":"__metadata","name":"thread_name","ph":"M","pid":98662,"tid":79875,"ts":0},
+    {"args":{"name":"Chrome_IOThread"},"cat":"__metadata","name":"thread_name","ph":"M","pid":98662,"tid":33283,"ts":0},
+    {"args":{"name":"StackSamplingProfiler"},"cat":"__metadata","name":"thread_name","ph":"M","pid":98662,"tid":6659,"ts":0},
+    {"args":{"name":"ThreadPoolServiceThread"},"cat":"__metadata","name":"thread_name","ph":"M","pid":98662,"tid":36867,"ts":0},
+    {"args":{"name":"ThreadPoolServiceThread"},"cat":"__metadata","name":"thread_name","ph":"M","pid":98673,"tid":35587,"ts":0},
+    {"args":{"name":"ThreadPoolServiceThread"},"cat":"__metadata","name":"thread_name","ph":"M","pid":98676,"tid":20483,"ts":0},
+    {"args":{"name":"Chrome_ChildIOThread"},"cat":"__metadata","name":"thread_name","ph":"M","pid":98676,"tid":13059,"ts":0},
+    {"args":{"name":"ThreadPoolForegroundWorker"},"cat":"__metadata","name":"thread_name","ph":"M","pid":98676,"tid":11779,"ts":0},
+    {"args":{"name":"ThreadPoolForegroundWorker"},"cat":"__metadata","name":"thread_name","ph":"M","pid":98676,"tid":19203,"ts":0},
+    {"args":{"name":"ThreadPoolForegroundWorker"},"cat":"__metadata","name":"thread_name","ph":"M","pid":98662,"tid":63747,"ts":0},
+    {"args":{"name":"ThreadPoolForegroundWorker"},"cat":"__metadata","name":"thread_name","ph":"M","pid":98673,"tid":32259,"ts":0},
+    {"args":{"name":"Browser"},"cat":"__metadata","name":"process_name","ph":"M","pid":98662,"tid":0,"ts":0},
+    {"args":{"name":"GPU Process"},"cat":"__metadata","name":"process_name","ph":"M","pid":98673,"tid":0,"ts":0},
+    {"args":{"name":"Renderer"},"cat":"__metadata","name":"process_name","ph":"M","pid":98676,"tid":0,"ts":0},
+    {"args":{"uptime":"17"},"cat":"__metadata","name":"process_uptime_seconds","ph":"M","pid":98662,"tid":0,"ts":0},
+    {"args":{"uptime":"17"},"cat":"__metadata","name":"process_uptime_seconds","ph":"M","pid":98673,"tid":0,"ts":0},
+    {"args":{"uptime":"16"},"cat":"__metadata","name":"process_uptime_seconds","ph":"M","pid":98676,"tid":0,"ts":0},
+    {"args":{"data":{"frameTreeNodeId":2,"frames":[{"frame":"CDC7FDACD95C50606A7BC08529E7F1CD","name":"","processId":98676,"url":"https://example.com/"}],"persistentIds":true}},"cat":"disabled-by-default-devtools.timeline","name":"TracingStartedInBrowser","ph":"I","pid":98662,"s":"t","tid":775,"ts":260758704187,"tts":489667},
+    {"args":{},"cat":"disabled-by-default-devtools.timeline","dur":99652,"name":"RunTask","ph":"X","pid":98676,"tdur":99335,"tid":775,"ts":260760721453,"tts":144263},
+    {"args":{"microtask_count":1},"cat":"v8.execute","dur":66,"name":"RunMicrotasks","ph":"X","pid":98676,"tdur":67,"tid":775,"ts":260760820980,"tts":243474},
+    {"args":{},"cat":"disabled-by-default-devtools.timeline","dur":1004488,"name":"RunTask","ph":"X","pid":98676,"tdur":997136,"tid":775,"ts":260761324398,"tts":243766},
+    {"args":{},"cat":"disabled-by-default-devtools.timeline","dur":1004344,"name":"EvaluateScript","ph":"X","pid":98676,"tdur":996992,"tid":775,"ts":260761324446,"tts":243813},
+    {"args":{"data":{"columnNumber":1,"lineNumber":1,"notStreamedReason":"inline script","streamed":false,"url":""},"fileName":""},"cat":"v8,devtools.timeline","dur":118,"name":"v8.compile","ph":"X","pid":98676,"tdur":124,"tid":775,"ts":260761324588,"tts":243955},
+    {"args":{"microtask_count":3},"cat":"v8.execute","dur":1003400,"name":"RunMicrotasks","ph":"X","pid":98676,"tdur":996049,"tid":775,"ts":260761325228,"tts":244595},
+    {"args":{"microtask_count":3},"cat":"v8.execute","dur":103,"name":"RunMicrotasks","ph":"X","pid":98676,"tdur":102,"tid":775,"ts":260762328684,"tts":1240700},
+    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+    {"args":{"sync_id":"__lighthouseTimespanStart__"},"cat":"__metadata","name":"clock_sync","ph":"c","pid":98662,"tid":775,"ts":260759206050,"tts":491817},
+    {"args":{"number":16},"cat":"__metadata","name":"num_cpus","ph":"M","pid":98662,"tid":0,"ts":260762832144},
+    {"args":{"number":16},"cat":"__metadata","name":"num_cpus","ph":"M","pid":98673,"tid":0,"ts":260762832156},
+    {"args":{"number":16},"cat":"__metadata","name":"num_cpus","ph":"M","pid":98676,"tid":0,"ts":260762832161},
+    {"args":{"sort_index":-5},"cat":"__metadata","name":"process_sort_index","ph":"M","pid":98676,"tid":775,"ts":260762832168},
+    {"args":{"sort_index":-6},"cat":"__metadata","name":"process_sort_index","ph":"M","pid":98662,"tid":63747,"ts":260762832171},
+    {"args":{"labels":"Example Domain"},"cat":"__metadata","name":"process_labels","ph":"M","pid":98676,"tid":775,"ts":260762832171},
+    {"args":{"sort_index":-1},"cat":"__metadata","name":"thread_sort_index","ph":"M","pid":98676,"tid":775,"ts":260762832174},
+    {"args":{"sort_index":-1},"cat":"__metadata","name":"process_sort_index","ph":"M","pid":98673,"tid":32259,"ts":260762832180}
+  ]
+}

lighthouse-core/test/lib/tracehouse/trace-processor-test.js

@@ -17,6 +17,7 @@ const noTracingStartedTrace = require('../../fixtures/traces/no-tracingstarted-m
 const preactTrace = require('../../fixtures/traces/preactjs.com_ts_of_undefined.json');
 const noFMPtrace = require('../../fixtures/traces/no_fmp_event.json');
 const noFCPtrace = require('../../fixtures/traces/airhorner_no_fcp.json');
+const timespanTrace = require('../../fixtures/traces/timespan-trace-m91.json');
 const noNavStartTrace = require('../../fixtures/traces/no_navstart_event.json');
 const backgroundTabTrace = require('../../fixtures/traces/backgrounded-tab-missing-paints.json');
 const lcpTrace = require('../../fixtures/traces/lcp-m78.json');
@@ -421,6 +422,16 @@ describe('TraceProcessor', () => {
 
         expect(trace.timestamps.timeOrigin).toEqual(713037332092);
       });
+
+      it('supports lighthouseMarker', () => {
+        const trace = TraceProcessor.processTrace(timespanTrace);
+
+        expect(trace.timings).toMatchObject({
+          traceEnd: 3626.13,
+        });
+
+        expect(trace.timestamps.timeOrigin).toEqual(260759206050);
+      });
     });
 
     describe('.processNavigation()', () => {

types/externs.d.ts

@@ -317,6 +317,7 @@ declare global {
       args: {
         fileName?: string;
         snapshot?: string;
+        sync_id?: string;
         beginData?: {
           frame?: string;
           startLine?: number;