Merge 75c28f1 into c3db893

lighthouse-core/lib/dependency-graph/simulator/connection-pool.js

@@ -74,8 +74,10 @@ module.exports = class ConnectionPool {
         throw new Error(`Could not find a connection for origin: ${origin}`);
       }
 
-      // Make sure each origin has minimum number of connections available for max throughput
-      while (connections.length < CONNECTIONS_PER_ORIGIN) connections.push(connections[0].clone());
+      // Make sure each origin has minimum number of connections available for max throughput.
+      // But only if it's not over H2 which maximizes throughput already.
+      const minConnections = connections[0].isH2() ? 1 : CONNECTIONS_PER_ORIGIN;
+      while (connections.length < minConnections) connections.push(connections[0].clone());
 
       this._connectionsByOrigin.set(origin, connections);
     }

lighthouse-core/test/audits/__snapshots__/metrics-test.js.snap

@@ -97,7 +97,7 @@ Object {
 exports[`Performance: metrics evaluates valid input correctly 1`] = `
 Object {
   "cumulativeLayoutShift": 0,
-  "estimatedInputLatency": 78,
+  "estimatedInputLatency": 81,
   "estimatedInputLatencyTs": undefined,
   "firstCPUIdle": 3351,
   "firstCPUIdleTs": undefined,
@@ -137,6 +137,6 @@ Object {
   "observedTraceEndTs": 225426711887,
   "speedIndex": 1676,
   "speedIndexTs": undefined,
-  "totalBlockingTime": 726,
+  "totalBlockingTime": 777,
 }
 `;

lighthouse-core/test/audits/byte-efficiency/render-blocking-resources-test.js

@@ -80,11 +80,9 @@ describe('Render blocking resources audit', () => {
         'url': 'https://fonts.googleapis.com/css?family=Fira+Sans+Condensed%3A400%2C400i%2C600%2C600i&subset=latin%2Clatin-ext&display=swap',
         'wastedMs': 440,
       },
-      {
-        'totalBytes': 621,
-        'url': 'https://fonts.googleapis.com/css?family=Montserrat',
-        'wastedMs': 440,
-      },
+      // Due to internal H2 simulation details, parallel HTTP/2 requests are pipelined which makes
+      // it look like Montserrat starts after Fira Sans finishes. It would be preferred
+      // if eventual simulation improvements list Montserrat here as well.
     ]);
   });
 

lighthouse-core/test/audits/dobetterweb/uses-http2-test.js

@@ -44,8 +44,8 @@ describe('Resources are fetched over http/2', () => {
     // make sure we flag all the rest
     expect(result.details.items).toHaveLength(60);
     // make sure we report savings
-    expect(result.numericValue).toMatchInlineSnapshot(`1030`);
-    expect(result.details.overallSavingsMs).toMatchInlineSnapshot(`1030`);
+    expect(result.numericValue).toMatchInlineSnapshot(`1310`);
+    expect(result.details.overallSavingsMs).toMatchInlineSnapshot(`1310`);
     // make sure we have a failing score
     expect(result.score).toBeLessThan(0.5);
   });
@@ -70,7 +70,7 @@ describe('Resources are fetched over http/2', () => {
     expect(urls).not.toContain(records[30].url);
     expect(result.details.items).toHaveLength(30);
     // make sure we report less savings
-    expect(result.numericValue).toMatchInlineSnapshot(`250`);
-    expect(result.details.overallSavingsMs).toMatchInlineSnapshot(`250`);
+    expect(result.numericValue).toMatchInlineSnapshot(`850`);
+    expect(result.details.overallSavingsMs).toMatchInlineSnapshot(`850`);
   });
 });

lighthouse-core/test/audits/timing-budget-test.js

@@ -28,7 +28,7 @@ describe('Performance: Timing budget audit', () => {
     context = {
       computedCache: new Map(),
       settings: {
-        throttlingMethod: 'simulate',
+        throttlingMethod: 'devtools',
       },
     };
   });
@@ -63,15 +63,15 @@ describe('Performance: Timing budget audit', () => {
       const items = result.details.items;
       // Failing Budget
       expect(items[0].label).toBeDisplayString('Estimated Input Latency');
-      expect(items[0].measurement).toBeCloseTo(77.8);
-      expect(items[0].overBudget).toBeCloseTo(67.8);
+      expect(items[0].measurement).toBeCloseTo(17.07);
+      expect(items[0].overBudget).toBeCloseTo(7.07);
     });
 
     it('calculates the "overBudget" column correctly', async () => {
       const result = await TimingBudgetAudit.audit(artifacts, context);
 
       // Failing Budget
-      expect(result.details.items[0].overBudget).toBeCloseTo(67.8);
+      expect(result.details.items[0].overBudget).toBeCloseTo(7.07);
 
       // Passing Budget
       expect(result.details.items[1].overBudget).toBeUndefined();

lighthouse-core/test/computed/metrics/__snapshots__/estimated-input-latency-test.js.snap

@@ -2,8 +2,8 @@
 
 exports[`Metrics: EIL should compute a simulated value 1`] = `
 Object {
-  "optimistic": 93,
+  "optimistic": 101,
   "pessimistic": 101,
-  "timing": 78,
+  "timing": 81,
 }
 `;

lighthouse-core/test/computed/metrics/__snapshots__/lantern-estimated-input-latency-test.js.snap

@@ -2,8 +2,8 @@
 
 exports[`Metrics: Lantern EIL should compute a simulated value 1`] = `
 Object {
-  "optimistic": 93,
+  "optimistic": 101,
   "pessimistic": 101,
-  "timing": 78,
+  "timing": 81,
 }
 `;

lighthouse-core/test/computed/metrics/timing-summary-test.js

@@ -19,7 +19,7 @@ describe('Timing summary', () => {
     expect(result.metrics).toMatchInlineSnapshot(`
       Object {
         "cumulativeLayoutShift": 0,
-        "estimatedInputLatency": 77.79999999999995,
+        "estimatedInputLatency": 80.93333333333328,
         "estimatedInputLatencyTs": undefined,
         "firstCPUIdle": 3351.3320000492963,
         "firstCPUIdleTs": undefined,
@@ -59,7 +59,7 @@ describe('Timing summary', () => {
         "observedTraceEndTs": 225426711887,
         "speedIndex": 1676.1335047609864,
         "speedIndexTs": undefined,
-        "totalBlockingTime": 726.4774999940994,
+        "totalBlockingTime": 776.9999999999995,
       }
     `);
     // Includes performance metrics

lighthouse-core/test/computed/metrics/total-blocking-time-test.js

@@ -22,12 +22,12 @@ describe('Metrics: TotalBlockingTime', () => {
       optimistic: Math.round(result.optimisticEstimate.timeInMs),
       pessimistic: Math.round(result.pessimisticEstimate.timeInMs),
     }).toMatchInlineSnapshot(`
-Object {
-  "optimistic": 676,
-  "pessimistic": 777,
-  "timing": 726,
-}
-`);
+      Object {
+        "optimistic": 777,
+        "pessimistic": 777,
+        "timing": 777,
+      }
+    `);
   });
 
   it('should compute an observed value', async () => {
@@ -94,42 +94,54 @@ Object {
       const fcpTimeMs = 1000;
       const interactiveTimeMs = 2000;
 
-      expect(TotalBlockingTime.calculateSumOfBlockingTime(
-        [{start: 1951, end: 2100, duration: 149}],
-        fcpTimeMs,
-        interactiveTimeMs
-      )).toBe(0); // Duration after clipping is 49, which is < 50.
-      expect(TotalBlockingTime.calculateSumOfBlockingTime(
-        [{start: 1950, end: 2100, duration: 150}],
-        fcpTimeMs,
-        interactiveTimeMs
-      )).toBe(0); // Duration after clipping is 50, so time after 50ms is 0ms.
-      expect(TotalBlockingTime.calculateSumOfBlockingTime(
-        [{start: 1949, end: 2100, duration: 151}],
-        fcpTimeMs,
-        interactiveTimeMs
-      )).toBe(1); // Duration after clipping is 51, so time after 50ms is 1ms.
+      expect(
+        TotalBlockingTime.calculateSumOfBlockingTime(
+          [{start: 1951, end: 2100, duration: 149}],
+          fcpTimeMs,
+          interactiveTimeMs
+        )
+      ).toBe(0); // Duration after clipping is 49, which is < 50.
+      expect(
+        TotalBlockingTime.calculateSumOfBlockingTime(
+          [{start: 1950, end: 2100, duration: 150}],
+          fcpTimeMs,
+          interactiveTimeMs
+        )
+      ).toBe(0); // Duration after clipping is 50, so time after 50ms is 0ms.
+      expect(
+        TotalBlockingTime.calculateSumOfBlockingTime(
+          [{start: 1949, end: 2100, duration: 151}],
+          fcpTimeMs,
+          interactiveTimeMs
+        )
+      ).toBe(1); // Duration after clipping is 51, so time after 50ms is 1ms.
     });
 
     it('clips properly if FCP falls in the middle of a task', () => {
       const fcpTimeMs = 1000;
       const interactiveTimeMs = 2000;
 
-      expect(TotalBlockingTime.calculateSumOfBlockingTime(
-        [{start: 900, end: 1049, duration: 149}],
-        fcpTimeMs,
-        interactiveTimeMs
-      )).toBe(0); // Duration after clipping is 49, which is < 50.
-      expect(TotalBlockingTime.calculateSumOfBlockingTime(
-        [{start: 900, end: 1050, duration: 150}],
-        fcpTimeMs,
-        interactiveTimeMs
-      )).toBe(0); // Duration after clipping is 50, so time after 50ms is 0ms.
-      expect(TotalBlockingTime.calculateSumOfBlockingTime(
-        [{start: 900, end: 1051, duration: 151}],
-        fcpTimeMs,
-        interactiveTimeMs
-      )).toBe(1); // Duration after clipping is 51, so time after 50ms is 1ms.
+      expect(
+        TotalBlockingTime.calculateSumOfBlockingTime(
+          [{start: 900, end: 1049, duration: 149}],
+          fcpTimeMs,
+          interactiveTimeMs
+        )
+      ).toBe(0); // Duration after clipping is 49, which is < 50.
+      expect(
+        TotalBlockingTime.calculateSumOfBlockingTime(
+          [{start: 900, end: 1050, duration: 150}],
+          fcpTimeMs,
+          interactiveTimeMs
+        )
+      ).toBe(0); // Duration after clipping is 50, so time after 50ms is 0ms.
+      expect(
+        TotalBlockingTime.calculateSumOfBlockingTime(
+          [{start: 900, end: 1051, duration: 151}],
+          fcpTimeMs,
+          interactiveTimeMs
+        )
+      ).toBe(1); // Duration after clipping is 51, so time after 50ms is 1ms.
     });
 
     // This can happen in the lantern metric case, where we use the optimistic

lighthouse-core/test/fixtures/lantern-master-accuracy.json

@@ -1,11 +1,11 @@
 {
   "roughEstimateOfFCP": {
     "p50": 0.292391744233104,
-    "p90": 0.5016256386437529,
+    "p90": 0.501397081651661,
     "p95": 0.5795269168026101
   },
   "roughEstimateOfFMP": {
-    "p50": 0.301651376146789,
+    "p50": 0.30206175397060275,
     "p90": 0.5385564466378778,
     "p95": 0.6641924269472893
   },
@@ -15,17 +15,17 @@
     "p95": 1.0080896079651525
   },
   "roughEstimateOfTTFCPUI": {
-    "p50": 0.3019386772996013,
-    "p90": 0.6660228191537149,
-    "p95": 0.9489925320557983
+    "p50": 0.28465238303454304,
+    "p90": 0.6509379230322955,
+    "p95": 0.8098063599218334
   },
   "roughEstimateOfTTI": {
-    "p50": 0.2841942294159043,
+    "p50": 0.3055258632709021,
     "p90": 0.6577081000373274,
     "p95": 0.743897672766033
   },
   "roughEstimateOfLCP": {
-    "p50": 0.21026850507982583,
+    "p50": 0.203757225433526,
     "p90": 0.6464365256124721,
     "p95": 0.8768898488120951
   }