Skip to content

Commit

Permalink
Add dynamic labels to the wall profiler (#73)
Browse files Browse the repository at this point in the history 
* Add dynamic labels for wall profiling

This adds dyanmic labels for wall profiling.

* Update test/profiler.test.ts

Co-authored-by: Bryan Huhta <[email protected]>

---------

Co-authored-by: Bryan Huhta <[email protected]>
  • Loading branch information
@simonswine @bryanhuhta
simonswine and bryanhuhta authored May 29, 2024
1 parent 9569d4b commit fb58341
Show file tree
Hide file tree
Showing 5 changed files with 169 additions and 43 deletions.
25 changes: 23 additions & 2 deletions src/index.ts
View file
Original file line number Diff line number Diff line change
Expand Up @@ -23,14 +23,32 @@ export function init(config: PyroscopeConfig = {}): void {
setProfiler(new PyroscopeProfiler(processedConfig))
}

// deprecated: please use getLabels
function getWallLabels(): Record<string, number | string> {
return getProfiler().wallProfiler.profiler.getLabels()
return getLabels()
}

// deprecated: please use setLabels
function setWallLabels(labels: Record<string, number | string>): void {
return setLabels(labels)
}

function getLabels(): Record<string, number | string> {
return getProfiler().wallProfiler.profiler.getLabels()
}

function setLabels(labels: Record<string, number | string>): void {
getProfiler().wallProfiler.profiler.setLabels(labels)
}

export function wrapWithLabels(
lbls: Record<string, string | number>,
fn: () => void,
...args: unknown[]
): void {
getProfiler().wallProfiler.profiler.wrapWithLabels(lbls, fn, ...args)
}

function startWallProfiling(): void {
getProfiler().wallProfiler.start()
}
Expand Down Expand Up @@ -76,9 +94,12 @@ function setLogger(logger: Logger): void {
export default {
SourceMapper,
expressMiddleware,
getWallLabels,
init,
getWallLabels,
setWallLabels,
getLabels,
setLabels,
wrapWithLabels,
start,
startHeapProfiling,
startWallProfiling,
Expand Down
18 changes: 12 additions & 6 deletions src/profilers/heap-profiler.ts
View file
Original file line number Diff line number Diff line change
Expand Up @@ -14,23 +14,29 @@ export interface HeapProfilerStartArgs {
}

export class HeapProfiler implements Profiler<HeapProfilerStartArgs> {
private labels: Record<string, number | string>
private lastProfiledAt: Date
private sourceMapper: SourceMapper | undefined

constructor() {
this.labels = {}
this.lastProfiledAt = new Date()
}

public getLabels(): Record<string, number | string> {
return this.labels
throw new Error("heap profiler doesn't support labels")
}

public wrapWithLabels(): void {
throw new Error("heap profiler doesn't support labels")
}

public profile(): ProfileExport {
log('profile')

const profile: Profile = heap.profile(undefined, this.sourceMapper, undefined)
const profile: Profile = heap.profile(
undefined,
this.sourceMapper,
undefined
)

const lastProfileStartedAt: Date = this.lastProfiledAt
this.lastProfiledAt = new Date()
Expand All @@ -42,8 +48,8 @@ export class HeapProfiler implements Profiler<HeapProfilerStartArgs> {
}
}

public setLabels(labels: Record<string, number | string>): void {
this.labels = labels
public setLabels(): void {
throw new Error("heap profiler doesn't support labels")
}

public start(args: HeapProfilerStartArgs): void {
Expand Down
6 changes: 6 additions & 0 deletions src/profilers/profiler.ts
View file
Original file line number Diff line number Diff line change
Expand Up @@ -5,6 +5,12 @@ export interface Profiler<TStartArgs> {

setLabels(labels: Record<string, number | string>): void

wrapWithLabels(
labels: Record<string, number | string>,
fn: () => void,
...args: unknown[]
): void

start(args: TStartArgs): void

stop(): ProfileExport | null
Expand Down
69 changes: 55 additions & 14 deletions src/profilers/wall-profiler.ts
View file
Original file line number Diff line number Diff line change
@@ -1,4 +1,4 @@
import { time, SourceMapper } from '@datadog/pprof'
import { time, SourceMapper, LabelSet, TimeProfileNode } from '@datadog/pprof'
import { Profile } from 'pprof-format'

import { ProfileExport } from '../profile-exporter'
Expand All @@ -16,27 +16,63 @@ export interface WallProfilerStartArgs {
collectCpuTime: boolean
}

export interface GenerateTimeLabelsArgs {
node: TimeProfileNode
context?: TimeProfileNodeContext
}

export interface TimeProfileNodeContext {
context: ProfilerContext
timestamp: bigint
cpuTime: number
}

export interface ProfilerContext {
labels?: LabelSet
}

// eslint-disable-next-line @typescript-eslint/no-explicit-any
type AnyWrappedCallback = any

export class WallProfiler implements Profiler<WallProfilerStartArgs> {
private labels: Record<string, number | string>
private lastProfiledAt: Date
private lastContext: ProfilerContext
private lastSamplingIntervalMicros!: number

constructor() {
this.labels = {}
this.lastContext = {}
this.lastProfiledAt = new Date()
}

public getLabels(): Record<string, number | string> {
return this.labels
public getLabels(): LabelSet {
return this.lastContext.labels ?? {}
}

public profile(): ProfileExport {
log('profile')
return this.innerProfile(true)
}

public setLabels(labels: Record<string, number | string>): void {
this.labels = labels
public wrapWithLabels(
lbls: LabelSet,
fn: () => void,
...args: unknown[]
): void {
const oldLabels = this.getLabels()
this.setLabels({
...oldLabels,
...lbls,
})
;(fn as AnyWrappedCallback)(...args)
this.setLabels({
...oldLabels,
})
}

public setLabels(labels: LabelSet): void {
this.newContext({
labels: labels,
})
}

public start(args: WallProfilerStartArgs): void {
Expand All @@ -53,7 +89,7 @@ export class WallProfiler implements Profiler<WallProfilerStartArgs> {
workaroundV8Bug: true,
collectCpuTime: args.collectCpuTime,
})
time.setContext({})
this.newContext({})
}
}

Expand All @@ -62,13 +98,18 @@ export class WallProfiler implements Profiler<WallProfilerStartArgs> {
return this.innerProfile(false)
}

private innerProfile(restart: boolean): ProfileExport {
time.setContext({})
private newContext(o: ProfilerContext) {
this.lastContext = o
time.setContext(o)
}

const profile: Profile = time.stop(
restart,
(): Record<string, number | string> => this.labels
)
private generateLabels(args: GenerateTimeLabelsArgs): LabelSet {
return { ...(args.context?.context.labels ?? {}) }
}

private innerProfile(restart: boolean): ProfileExport {
this.newContext({})
const profile: Profile = time.stop(restart, this.generateLabels)

const lastProfileStartedAt: Date = this.lastProfiledAt
this.lastProfiledAt = new Date()
Expand Down
94 changes: 73 additions & 21 deletions test/profiler.test.ts
View file
Original file line number Diff line number Diff line change
Expand Up @@ -4,26 +4,35 @@ import busboy from 'busboy'
import { Profile } from 'pprof-format'
import zlib from 'zlib'

type Numeric = number | bigint

const extractProfile = (
req: express.Request,
res: express.Response,
callback: (p: Profile, name: String) => void
callback: (p: Profile, name: string) => void
) => {
const bb = busboy({ headers: req.headers })
bb.on('file', (name, file) => {
file
.toArray()
.then((values) => callback(
Profile.decode(zlib.gunzipSync(values[0])),
name,
))
.then((values) =>
callback(Profile.decode(zlib.gunzipSync(values[0])), name)
)
})
bb.on('close', () => {
res.send('ok')
})
req.pipe(bb)
}

const doWork = (d: number): void => {
const time = +new Date() + d * 1000
let i = 0
while (+new Date() < time) {
i = i + Math.random()
}
}

describe('common behaviour of profilers', () => {
it('should call a server on startCpuProfiling and clear gracefully', (done) => {
Pyroscope.init({
Expand Down Expand Up @@ -142,7 +151,7 @@ describe('common behaviour of profilers', () => {
})()
})

it('should have labels on wall profile', (done) => {
it('should have dynamic labels on wall profile', (done) => {
Pyroscope.init({
serverAddress: 'http://localhost:4446',
appName: 'nodejs',
Expand All @@ -155,37 +164,81 @@ describe('common behaviour of profilers', () => {
samplingIntervalMicros: 100,
},
})
Pyroscope.setWallLabels({
vehicle: 'car',
})
const app = express()
const server = app.listen(4446, () => {
Pyroscope.startWallProfiling()
Pyroscope.wrapWithLabels(
{
vehicle: 'car',
},
() => {
doWork(0.2)
Pyroscope.wrapWithLabels(
{
brand: 'mercedes',
},
() => {
doWork(0.2)
}
)
}
)
})

let closeInvoked = false
const valuesPerLabel = new Map<string, Array<number>>()

app.post('/ingest', (req, res) => {
expect(req.query['spyName']).toEqual('nodespy')
expect(req.query['name']).toEqual('nodejs{}')
extractProfile(req, res, (p: Profile) => {
const s = (idx: Number | bigint) => p.stringTable.strings[Number(idx)]
// now take the first sample and check if it has the label as expected
expect(s(p.sample[0].label[0].key)).toEqual('vehicle')
expect(s(p.sample[0].label[0].str)).toEqual('car')
const s = (idx: Numeric): string => p.stringTable.strings[Number(idx)]

// expect sample, wall types
expect(p.sampleType.map((x) => `${s(x.type)}=${s(x.unit)}`)).toEqual([
'samples=count',
'wall=nanoseconds',
])
// aggregate per labels
p.sample.forEach((x) => {
const key: string = JSON.stringify(
x.label.reduce(
(result, current) => ({
...result,
[s(current.key)]: s(current.str),
}),
{}
)
)
const prev = valuesPerLabel.get(key) ?? [0, 0, 0]
valuesPerLabel.set(
key,
x.value.map((a, i) => Number(a) + prev[i])
)
})
})

if (!closeInvoked) {
closeInvoked = true
;(async () => {
await Pyroscope.stopWallProfiling()
server.close(() => {
// ensure we contain everything expected
const emptyLabels = JSON.stringify({})
const vehicleOnly = JSON.stringify({ vehicle: 'car' })
const vehicleAndBrand = JSON.stringify({
vehicle: 'car',
brand: 'mercedes',
})

expect(valuesPerLabel.keys()).toContain(emptyLabels)
expect(valuesPerLabel.keys()).toContain(vehicleOnly)
expect(valuesPerLabel.keys()).toContain(vehicleAndBrand)

const valuesVehicleOnly = valuesPerLabel.get(vehicleOnly) ?? [0, 0]
const valuesVehicleAndBrand = valuesPerLabel.get(
vehicleAndBrand
) ?? [0, 0]

// ensure the wall time is within a 20% range of each other
const ratio = valuesVehicleOnly[1] / valuesVehicleAndBrand[1]
expect(ratio).toBeGreaterThan(0.8)
expect(ratio).toBeLessThan(1.2)

done()
})
})()
Expand Down Expand Up @@ -213,13 +266,12 @@ describe('common behaviour of profilers', () => {
})

let closeInvoked = false

app.post('/ingest', (req, res) => {
expect(req.query['spyName']).toEqual('nodespy')
expect(req.query['name']).toEqual('nodejs{}')

extractProfile(req, res, (p: Profile) => {
const s = (idx: Number | bigint) => p.stringTable.strings[Number(idx)]
const s = (idx: number | bigint) => p.stringTable.strings[Number(idx)]
// expect sample, wall and cpu types
expect(p.sampleType.map((x) => `${s(x.type)}=${s(x.unit)}`)).toEqual([
'samples=count',
Expand Down

0 comments on commit fb58341

Please sign in to comment.