Stackprof: weight on-cpu samples by period rather than timestamp delta

sample/programs/ruby/simple.rb

@@ -5,6 +5,7 @@ def a
   for i in 0..100 do
     b
     c
+    e
   end
 end
 
@@ -28,8 +29,13 @@ def d
   prod
 end
 
-profile = StackProf.run(mode: :wall, raw: true) do
+def e
+  sleep 0.05
+end
+
+mode = (ARGV[0] || :wall).to_sym
+profile = StackProf.run(mode: mode, raw: true) do
   a
 end
 
-puts JSON.generate(profile)
+puts JSON.generate(profile)

src/import/stackprof.test.ts

@@ -1,3 +1,5 @@
+import { readFileSync } from 'fs';
+import { importProfileGroupFromText } from '.'
 import {checkProfileSnapshot} from '../lib/test-utils'
 
 test('importFromStackprof', async () => {
@@ -11,3 +13,26 @@ test('importFromStackprof object mode', async () => {
 test('importFromStackprof when a profile has a frame with no name', async () => {
   await checkProfileSnapshot('./sample/profiles/stackprof/stackprof-last-frame-no-name.json')
 })
+
+describe('importCpuProfileWithProperWeights', () => {
+  test('importFromStackprof cpu mode snapshot', async () => {
+    await checkProfileSnapshot('./sample/profiles/stackprof/simple-cpu-stackprof.json')
+  })
+
+  test('uses samples count for weight when importing cpu profile', async () => {
+
+    const profileFile = readFileSync('./sample/profiles/stackprof/simple-cpu-stackprof.json')
+    const profileGroup = await importProfileGroupFromText('simple-cpu-stackprof.json', profileFile.toString())
+    expect(profileGroup).not.toBeNull()
+
+    if (profileGroup) {
+      const profile = profileGroup.profiles[profileGroup.indexToView]
+      expect(profile).not.toBeNull()
+
+      if (profile) {
+        expect(profile.getWeightUnit()).toBe('microseconds')
+        expect(profile.getTotalWeight()).toBe(489000)
+      }
+    }
+  })
+})

src/import/stackprof.ts

@@ -1,7 +1,7 @@
 // https://github.com/tmm1/stackprof
 
 import {Profile, FrameInfo, StackListProfileBuilder} from '../lib/profile'
-import {TimeFormatter} from '../lib/value-formatters'
+import {RawValueFormatter, TimeFormatter} from '../lib/value-formatters'
 
 interface StackprofFrame {
   name?: string
@@ -15,14 +15,13 @@ export interface StackprofProfile {
   raw: number[]
   raw_timestamp_deltas: number[]
   samples: number
+  interval: number
 }
 
 export function importFromStackprof(stackprofProfile: StackprofProfile): Profile {
-  const {frames, mode, raw, raw_timestamp_deltas, samples} = stackprofProfile
-  const objectMode = mode == 'object'
-
-  const size = objectMode ? samples : stackprofProfile.raw_timestamp_deltas.reduce((a, b) => a + b, 0)
-  const profile = new StackListProfileBuilder(size)
+  const {frames, mode, raw, raw_timestamp_deltas, interval} = stackprofProfile
+  const profile = new StackListProfileBuilder()
+  profile.setValueFormatter(new TimeFormatter('microseconds')) // default to time format unless we're in object mode
 
   let sampleIndex = 0
 
@@ -50,23 +49,24 @@ export function importFromStackprof(stackprofProfile: StackprofProfile): Profile
     }
     const nSamples = raw[i++]
 
-    if (objectMode) {
-      profile.appendSampleWithWeight(stack, nSamples)
-    } else {
-      let sampleDuration = 0
-      for (let j = 0; j < nSamples; j++) {
-        sampleDuration += raw_timestamp_deltas[sampleIndex++]
-      }
-
-      profile.appendSampleWithWeight(stack, sampleDuration)
+    switch (mode) {
+      case 'object':
+        profile.appendSampleWithWeight(stack, nSamples)
+        profile.setValueFormatter(new RawValueFormatter())
+        break
+      case 'cpu':
+        profile.appendSampleWithWeight(stack, nSamples * interval)
+        break
+      default:
+        let sampleDuration = 0
+        for (let j = 0; j < nSamples; j++) {
+          sampleDuration += raw_timestamp_deltas[sampleIndex++]
+        }
+        profile.appendSampleWithWeight(stack, sampleDuration)
     }
 
     prevStack = stack
   }
 
-  if (!objectMode) {
-    profile.setValueFormatter(new TimeFormatter('microseconds'))
-  }
-
   return profile.build()
 }