Import v8 cpu profile (old format) (#177)

As said on #170, i added the support for the old format used by https://github.com/hyj1991/v8-profiler-node8 (which is currently used for pm2.io).

sample/profiles/node/10.11.0/example.cpuprofile

@@ -0,0 +1 @@
+{"head":{"functionName":"(root)","url":"","lineNumber":-1,"bailoutReason":"","id":1,"scriptId":0,"hitCount":0,"children":[{"functionName":"","url":"","lineNumber":0,"callUID":1,"bailoutReason":"","id":2,"scriptId":0,"hitCount":0,"children":[{"functionName":"a","url":"","lineNumber":0,"callUID":2,"bailoutReason":"","id":3,"scriptId":0,"hitCount":0,"children":[{"functionName":"b","url":"","lineNumber":5,"callUID":3,"bailoutReason":"","id":4,"scriptId":0,"hitCount":0,"children":[{"functionName":"d","url":"","lineNumber":13,"callUID":4,"bailoutReason":"","id":5,"scriptId":0,"hitCount":14,"children":[]}]},{"functionName":"c","url":"","lineNumber":9,"callUID":3,"bailoutReason":"","id":6,"scriptId":0,"hitCount":0,"children":[{"functionName":"d","url":"","lineNumber":13,"callUID":6,"bailoutReason":"","id":7,"scriptId":0,"hitCount":14,"children":[]}]}]}]}]},"startTime":163140,"endTime":163140,"samples":[2,5,5,5,5,5,5,5,5,5,5,5,5,5,5,7,7,7,7,7,7,7,7,7,7,7,7,7,7],"timestamps":[163140599286,163140610861,163140611921,163140612966,163140614236,163140615507,163140616694,163140617968,163140619238,163140620258,163140621507,163140622765,163140624037,163140625303,163140626378,163140627649,163140628923,163140630191,163140631457,163140632746,163140634032,163140635304,163140636440,163140637716,163140638990,163140640255,163140641520,163140642791,163140644063,163140645206]}

sample/programs/javascript/convertToOld.js

@@ -0,0 +1,60 @@
+/*
+* This script is used to reconstruct an cpu profile from chrome with an old format
+* still used in nodejs with v8-profiler
+*/
+const fs = require('fs')
+
+const data = JSON.parse(fs.readFileSync('../../profiles/Chrome/65/simple.cpuprofile').toString())
+
+const _convertTimeDeltas = (profile) => {
+  if (!profile.timeDeltas) return null
+  let lastTimeUsec = profile.startTime
+  const timestamps = new Array(profile.timeDeltas.length + 1)
+  for (let i = 0; i < profile.timeDeltas.length; ++i) {
+    timestamps[i] = lastTimeUsec
+    lastTimeUsec += profile.timeDeltas[i]
+  }
+  timestamps[profile.timeDeltas.length] = lastTimeUsec
+  return timestamps
+}
+
+const reformatNode = node => {
+  if (!node.children) node.children = []
+
+  node.children = node.children.map(childID => {
+    if (typeof childID !== 'number') return childID
+    const childNode = data.nodes.find(node => node.id === childID)
+    if (typeof childNode !== 'object') return null
+    childNode.callUID = node.id
+    return childNode
+  })
+  return {
+    functionName: node.callFrame.functionName,
+    url: node.callFrame.url,
+    lineNumber: node.callFrame.lineNumber,
+    callUID: node.callUID,
+    bailoutReason: '',
+    id: node.id,
+    scriptId: 0,
+    hitCount: node.hitCount,
+    children: node.children.map(reformatNode)
+  }
+}
+
+// reformat then only keep the root as top level node
+const nodes = data.nodes
+  .map(reformatNode)
+  .filter(node => node.functionName === '(root)')[0]
+
+// since it can be undefined, create an array so execution still works
+if (!data.timeDeltas) {
+  data.timeDeltas = []
+}
+
+fs.writeFileSync('./new.cpuprofile', JSON.stringify({
+  head: nodes,
+  startTime: Math.floor(data.startTime / 1000000),
+  endTime: Math.floor(data.endTime / 1000000),
+  samples: data.samples,
+  timestamps: _convertTimeDeltas(data)
+}))

src/import/__snapshots__/chrome.test.ts.snap

@@ -1357,3 +1357,66 @@ exports[`importFromChromeTimeline Workers Chrome 70: profileGroup.name 1`] = `"w
 exports[`importFromChromeTimeline: indexToView 1`] = `0`;
 
 exports[`importFromChromeTimeline: profileGroup.name 1`] = `"simple-timeline.json"`;
+
+exports[`importFromV8Profiler Node 10 1`] = `
+Object {
+  "frames": Array [
+    Frame {
+      "col": 0,
+      "file": "",
+      "key": "(anonymous)::0:0",
+      "line": 0,
+      "name": "(anonymous)",
+      "selfWeight": 11575,
+      "totalWeight": 44777,
+    },
+    Frame {
+      "col": 0,
+      "file": "",
+      "key": "a::0:0",
+      "line": 0,
+      "name": "a",
+      "selfWeight": 0,
+      "totalWeight": 33202,
+    },
+    Frame {
+      "col": 0,
+      "file": "",
+      "key": "b::5:0",
+      "line": 5,
+      "name": "b",
+      "selfWeight": 0,
+      "totalWeight": 16788,
+    },
+    Frame {
+      "col": 0,
+      "file": "",
+      "key": "d::13:0",
+      "line": 13,
+      "name": "d",
+      "selfWeight": 33202,
+      "totalWeight": 33202,
+    },
+    Frame {
+      "col": 0,
+      "file": "",
+      "key": "c::9:0",
+      "line": 9,
+      "name": "c",
+      "selfWeight": 0,
+      "totalWeight": 16414,
+    },
+  ],
+  "name": "example.cpuprofile",
+  "stacks": Array [
+    " 599.29ms",
+    "(anonymous) 11.57ms",
+    "(anonymous);a;b;d 16.79ms",
+    "(anonymous);a;c;d 16.41ms",
+  ],
+}
+`;
+
+exports[`importFromV8Profiler Node 10: indexToView 1`] = `0`;
+
+exports[`importFromV8Profiler Node 10: profileGroup.name 1`] = `"example.cpuprofile"`;

src/import/chrome.test.ts

@@ -12,6 +12,10 @@ test('importFromChromeTimeline Chrome 69', async () => {
   await checkProfileSnapshot('./sample/profiles/Chrome/69/simple.json')
 })
 
+test('importFromV8Profiler Node 10', async () => {
+  await checkProfileSnapshot('./sample/profiles/node/10.11.0/example.cpuprofile')
+})
+
 test('importFromChromeTimeline Workers Chrome 70', async () => {
   await checkProfileSnapshot('./sample/profiles/Chrome/70/worker.json')
 })

src/import/chrome.ts

@@ -1,6 +1,7 @@
 import {Profile, FrameInfo, CallTreeProfileBuilder, ProfileGroup} from '../lib/profile'
 import {getOrInsert, lastOf, sortBy, itForEach} from '../lib/utils'
 import {TimeFormatter} from '../lib/value-formatters'
+import {chromeTreeToNodes, OldCPUProfile} from './v8cpuFormatter'
 
 // See: https://github.com/v8/v8/blob/master/src/inspector/js_protocol.json
 
@@ -31,7 +32,7 @@ interface CPUProfileCallFrame {
   url: string
 }
 
-interface CPUProfileNode {
+export interface CPUProfileNode {
   callFrame: CPUProfileCallFrame
   hitCount: number
   id: number
@@ -40,7 +41,7 @@ interface CPUProfileNode {
   parent?: CPUProfileNode
 }
 
-interface CPUProfile {
+export interface CPUProfile {
   startTime: number
   endTime: number
   nodes: CPUProfileNode[]
@@ -312,3 +313,7 @@ export function importFromChromeCPUProfile(chromeProfile: CPUProfile): Profile {
   profile.setValueFormatter(new TimeFormatter('microseconds'))
   return profile.build()
 }
+
+export function importFromOldV8CPUProfile(content: OldCPUProfile): Profile {
+  return importFromChromeCPUProfile(chromeTreeToNodes(content))
+}

src/import/index.ts

@@ -1,7 +1,12 @@
 import {Profile, ProfileGroup} from '../lib/profile'
 import {FileSystemDirectoryEntry} from './file-system-entry'
 
-import {importFromChromeCPUProfile, importFromChromeTimeline, isChromeTimeline} from './chrome'
+import {
+  importFromChromeCPUProfile,
+  importFromChromeTimeline,
+  isChromeTimeline,
+  importFromOldV8CPUProfile,
+} from './chrome'
 import {importFromStackprof} from './stackprof'
 import {importFromInstrumentsDeepCopy, importFromInstrumentsTrace} from './instruments'
 import {importFromBGFlameGraph} from './bg-flamegraph'
@@ -84,9 +89,6 @@ async function _importProfileGroup(dataSource: ProfileDataSource): Promise<Profi
   if (fileName.endsWith('.speedscope.json')) {
     console.log('Importing as speedscope json file')
     return importSpeedscopeProfiles(JSON.parse(contents))
-  } else if (fileName.endsWith('.cpuprofile')) {
-    console.log('Importing as Chrome CPU Profile')
-    return toGroup(importFromChromeCPUProfile(JSON.parse(contents)))
   } else if (fileName.endsWith('.chrome.json') || /Profile-\d{8}T\d{6}/.exec(fileName)) {
     console.log('Importing as Chrome Timeline')
     return importFromChromeTimeline(JSON.parse(contents), fileName)
@@ -123,11 +125,14 @@ async function _importProfileGroup(dataSource: ProfileDataSource): Promise<Profi
       console.log('Importing as Firefox profile')
       return toGroup(importFromFirefox(parsed))
     } else if (isChromeTimeline(parsed)) {
-      console.log('Importing as Chrome CPU Profile')
+      console.log('Importing as Chrome Timeline')
       return importFromChromeTimeline(parsed, fileName)
     } else if ('nodes' in parsed && 'samples' in parsed && 'timeDeltas' in parsed) {
-      console.log('Importing as Chrome Timeline')
+      console.log('Importing as Chrome CPU Profile')
       return toGroup(importFromChromeCPUProfile(parsed))
+    } else if ('head' in parsed && 'samples' in parsed && 'timestamps' in parsed) {
+      console.log('Importing as Chrome CPU Profile (old format)')
+      return toGroup(importFromOldV8CPUProfile(parsed))
     } else if ('mode' in parsed && 'frames' in parsed) {
       console.log('Importing as stackprof profile')
       return toGroup(importFromStackprof(parsed))

src/import/v8cpuFormatter.ts

@@ -0,0 +1,71 @@
+import {CPUProfile, CPUProfileNode} from './chrome'
+
+/**
+ * This importer handles an old format used by the C++ API of V8. This format is still used by v8-profiler-node8.
+ * There are two differences between the two formats:
+ *  - Nodes are a tree in the old format and a flat array in the new format
+ *  - Weights are timestamps in the old format and deltas in the new format.
+ *
+ * For more information, see https://github.com/hyj1991/v8-profiler-node8
+ */
+
+interface OldCPUProfileNode {
+  functionName: string
+  lineNumber: number
+  scriptId: string
+  url: string
+  hitCount: number
+  bailoutReason: string
+  id: number
+  children: OldCPUProfileNode[]
+}
+
+export interface OldCPUProfile {
+  startTime: number
+  endTime: number
+  head: OldCPUProfileNode
+  samples: number[]
+  timestamps: number[]
+}
+
+function treeToArray(root: OldCPUProfileNode): CPUProfileNode[] {
+  const nodes: CPUProfileNode[] = []
+  function visit(node: OldCPUProfileNode) {
+    nodes.push({
+      id: node.id,
+      callFrame: {
+        columnNumber: 0,
+        functionName: node.functionName,
+        lineNumber: node.lineNumber,
+        scriptId: node.scriptId,
+        url: node.url,
+      },
+      hitCount: node.hitCount,
+      children: node.children.map(child => child.id),
+    })
+    node.children.forEach(visit)
+  }
+  visit(root)
+  return nodes
+}
+
+function timestampsToDeltas(timestamps: number[], startTime: number): number[] {
+  return timestamps.map((timestamp, index) => {
+    const lastTimestamp = index === 0 ? startTime * 1000000 : timestamps[index - 1]
+    return timestamp - lastTimestamp
+  })
+}
+
+/**
+ * Convert the old tree-based format to the new flat-array based format
+ */
+export function chromeTreeToNodes(content: OldCPUProfile): CPUProfile {
+  // Note that both startTime and endTime are now in microseconds
+  return {
+    samples: content.samples,
+    startTime: content.startTime * 1000000,
+    endTime: content.endTime * 1000000,
+    nodes: treeToArray(content.head),
+    timeDeltas: timestampsToDeltas(content.timestamps, content.startTime),
+  }
+}