n8n/packages/testing/playwright/utils/performance-helper.ts
2026-04-23 10:36:02 +00:00

436 lines
13 KiB
TypeScript

import type { Page, TestInfo } from '@playwright/test';
import type { MetricsHelper } from 'n8n-containers';
import { createWriteStream } from 'node:fs';
import { mkdir, writeFile } from 'node:fs/promises';
import { Readable } from 'node:stream';
import { pipeline } from 'node:stream/promises';
import type { ReadableStream as NodeReadableStream } from 'node:stream/web';
interface HeapSnapshotResult {
success: boolean;
filePath?: string;
sizeBytes?: number;
sizeMB?: number;
message?: string;
}
const HEAP_USED_QUERY = 'n8n_nodejs_heap_size_used_bytes / 1024 / 1024';
const HEAP_TOTAL_QUERY = 'n8n_nodejs_heap_size_total_bytes / 1024 / 1024';
const RSS_QUERY = 'n8n_process_resident_memory_bytes / 1024 / 1024';
const PSS_QUERY = 'n8n_process_pss_bytes / 1024 / 1024';
export async function measurePerformance(
page: Page,
actionName: string,
actionFn: () => Promise<void>,
): Promise<number> {
await page.evaluate((name) => performance.mark(`${name}-start`), actionName);
await actionFn();
return await page.evaluate((name) => {
performance.mark(`${name}-end`);
performance.measure(name, `${name}-start`, `${name}-end`);
const measure = performance.getEntriesByName(name)[0] as PerformanceMeasure;
return measure.duration;
}, actionName);
}
export async function getAllPerformanceMetrics(page: Page) {
return await page.evaluate(() => {
const metrics: Record<string, number> = {};
const measures = performance.getEntriesByType('measure') as PerformanceMeasure[];
measures.forEach((m) => (metrics[m.name] = m.duration));
return metrics;
});
}
/** Attach a performance metric for collection by the metrics reporter */
export async function attachMetric(
testInfo: TestInfo,
metricName: string,
value: number,
unit?: string,
dimensions?: Record<string, string | number>,
): Promise<void> {
await testInfo.attach(`metric:${metricName}`, {
body: JSON.stringify({ value, unit, dimensions }),
});
// Currents native format — surfaces metrics in their analytics dashboard
testInfo.annotations.push({
type: 'currents:metric',
description: JSON.stringify({
name: metricName,
value,
type: Number.isInteger(value) ? 'integer' : 'float',
...(unit && { unit: unit.toLowerCase() }),
}),
});
}
export interface StableHeapOptions {
maxWaitMs?: number;
checkIntervalMs?: number;
thresholdMB?: number;
stableReadingsRequired?: number;
logGC?: boolean;
}
export interface StableHeapResult {
heapUsedMB: number;
heapTotalMB: number;
rssMB: number;
pssMB: number | null;
nonHeapOverheadMB: number;
stabilizationTimeMs: number;
readingsCount: number;
}
/**
* Trigger GC and wait for heap memory to stabilize.
* Collects RSS, PSS, and heap total samples during the stabilization window
* and returns median values to reduce point-in-time noise.
*/
export async function getStableHeap(
baseUrl: string,
metrics: MetricsHelper,
options: StableHeapOptions = {},
): Promise<StableHeapResult> {
const {
maxWaitMs = 60000,
checkIntervalMs = 5000,
thresholdMB = 2,
stableReadingsRequired = 2,
logGC = true,
} = options;
await triggerGC(baseUrl, logGC);
return await waitForStableMemory(metrics, {
maxWaitMs,
checkIntervalMs,
thresholdMB,
stableReadingsRequired,
});
}
async function triggerGC(baseUrl: string, log: boolean): Promise<void> {
const response = await fetch(`${baseUrl}/rest/e2e/gc`, { method: 'POST' });
if (!response.ok) {
throw new Error(`GC endpoint returned ${response.status}: ${response.statusText}`);
}
const result = (await response.json()) as { data?: { success: boolean; message: string } };
if (!result.data?.success) {
throw new Error(`GC failed: ${result.data?.message ?? 'Unknown error'}`);
}
if (log) {
console.log(`[GC] ${result.data.message}`);
}
}
interface StabilizationConfig {
maxWaitMs: number;
checkIntervalMs: number;
thresholdMB: number;
stableReadingsRequired: number;
}
interface MemorySamples {
heapTotal: number[];
rss: number[];
pss: number[];
}
function median(values: number[]): number {
if (values.length === 0) return 0;
const sorted = [...values].sort((a, b) => a - b);
const mid = Math.floor(sorted.length / 2);
return sorted.length % 2 !== 0 ? sorted[mid] : (sorted[mid - 1] + sorted[mid]) / 2;
}
async function collectAdditionalSamples(
metrics: MetricsHelper,
samples: MemorySamples,
): Promise<void> {
try {
const results = await Promise.all([
metrics.query(HEAP_TOTAL_QUERY),
metrics.query(RSS_QUERY),
metrics.query(PSS_QUERY),
]);
if (results[0]?.[0]) samples.heapTotal.push(results[0][0].value);
if (results[1]?.[0]) samples.rss.push(results[1][0].value);
if (results[2]?.[0]) samples.pss.push(results[2][0].value);
} catch {
// Non-critical, skip this sample
}
}
async function waitForStableMemory(
metrics: MetricsHelper,
config: StabilizationConfig,
): Promise<StableHeapResult> {
const { maxWaitMs, checkIntervalMs, thresholdMB, stableReadingsRequired } = config;
const startTime = Date.now();
let lastValue = 0;
let stableCount = 0;
let readingsCount = 0;
const samples: MemorySamples = { heapTotal: [], rss: [], pss: [] };
while (Date.now() - startTime < maxWaitMs) {
const result = await metrics.waitForMetric(HEAP_USED_QUERY, {
timeoutMs: checkIntervalMs,
intervalMs: 1000,
});
if (result) {
readingsCount++;
const currentValue = result.value;
await collectAdditionalSamples(metrics, samples);
const delta = Math.abs(currentValue - lastValue);
if (lastValue > 0 && delta < thresholdMB) {
stableCount++;
if (stableCount >= stableReadingsRequired) {
const stabilizationTimeMs = Date.now() - startTime;
const heapUsedMB = currentValue;
const heapTotalMB = median(samples.heapTotal);
const rssMB = median(samples.rss);
const pssMB = samples.pss.length > 0 ? median(samples.pss) : null;
// Can theoretically go negative if RSS/heapTotal medians come from slightly
// different sample windows. A negative value would indicate a measurement
// timing issue — don't clamp to 0, surface it for investigation.
const nonHeapOverheadMB = rssMB - heapTotalMB;
console.log(
`[STABILIZATION] Memory stabilized after ${stabilizationTimeMs}ms (${readingsCount} readings)\n` +
` Heap Used: ${heapUsedMB.toFixed(2)} MB\n` +
` Heap Total: ${heapTotalMB.toFixed(2)} MB (median of ${samples.heapTotal.length})\n` +
` RSS: ${rssMB.toFixed(2)} MB (median of ${samples.rss.length})\n` +
` PSS: ${pssMB?.toFixed(2) ?? 'N/A'} MB${pssMB !== null ? ` (median of ${samples.pss.length})` : ''}\n` +
` Non-Heap Overhead: ${nonHeapOverheadMB.toFixed(2)} MB`,
);
return {
heapUsedMB,
heapTotalMB,
rssMB,
pssMB,
nonHeapOverheadMB,
stabilizationTimeMs,
readingsCount,
};
}
} else {
stableCount = 0;
}
lastValue = currentValue;
}
await new Promise((resolve) => setTimeout(resolve, checkIntervalMs));
}
throw new Error(
`Memory did not stabilize within ${maxWaitMs}ms. ` +
`Last: ${lastValue.toFixed(2)} MB (${readingsCount} readings)`,
);
}
/**
* Trigger a V8 heap snapshot on the n8n server, download it locally, and
* return the local file path for programmatic analysis (e.g., memlab).
*/
export async function takeHeapSnapshot(
baseUrl: string,
testInfo: TestInfo,
label: string,
): Promise<string | null> {
// Step 1: Trigger snapshot on server
const createRes = await fetch(`${baseUrl}/rest/e2e/heap-snapshot`, { method: 'POST' });
if (!createRes.ok) {
console.warn(`[HEAP-SNAPSHOT] Create failed: ${createRes.status}`);
return null;
}
const result = (await createRes.json()) as { data?: HeapSnapshotResult };
const snapshot = result.data;
if (!snapshot?.success || !snapshot.filePath) {
console.warn(`[HEAP-SNAPSHOT] Failed: ${snapshot?.message ?? 'Unknown error'}`);
return null;
}
await attachMetric(testInfo, `heap-snapshot-${label}-size`, snapshot.sizeMB ?? 0, 'MB');
// Step 2: Download the snapshot file from the server
const filename = snapshot.filePath.split('/').pop()!;
const downloadRes = await fetch(`${baseUrl}/rest/e2e/heap-snapshot/${filename}`);
if (!downloadRes.ok || !downloadRes.body) {
console.warn(`[HEAP-SNAPSHOT] Download failed: ${downloadRes.status}`);
return null;
}
const localPath = `${testInfo.outputDir}/${label}.heapsnapshot`;
await mkdir(testInfo.outputDir, { recursive: true });
await pipeline(
Readable.fromWeb(downloadRes.body as unknown as NodeReadableStream),
createWriteStream(localPath),
);
console.log(`[HEAP-SNAPSHOT] "${label}" saved: ${localPath} (${snapshot.sizeMB} MB)`);
return localPath;
}
// ---------------------------------------------------------------------------
// RSS breakdown via /proc/self/smaps
// ---------------------------------------------------------------------------
export interface RssMapping {
name: string;
rssMB: number;
pssMB: number;
count: number;
}
export interface RssBreakdown {
processMemoryUsage: {
rss: number;
heapTotal: number;
heapUsed: number;
external: number;
arrayBuffers: number;
};
rollup: Record<string, number> | null;
mappings: RssMapping[] | null;
}
export interface RssBreakdownDiff {
baselineRssMB: number;
finalRssMB: number;
deltaRssMB: number;
topGrowers: Array<{ name: string; baselineRssMB: number; finalRssMB: number; deltaMB: number }>;
topNew: Array<{ name: string; rssMB: number }>;
rollupDiff: Record<string, { baseline: number; final: number; delta: number }> | null;
}
/**
* Fetch the RSS breakdown from the server, save it to the output dir, and return parsed data.
* Falls back gracefully on macOS / non-Linux (smaps not available).
*/
export async function captureRssBreakdown(
baseUrl: string,
outputDir: string,
label: string,
): Promise<RssBreakdown | null> {
try {
const res = await fetch(`${baseUrl}/rest/e2e/memory-maps`);
if (!res.ok) {
console.warn(`[RSS] memory-maps endpoint returned ${res.status}`);
return null;
}
const body = (await res.json()) as { data?: RssBreakdown & { raw?: string } };
const data = body.data;
if (!data) return null;
await mkdir(outputDir, { recursive: true });
// Save raw smaps if available
if (data.raw) {
await writeFile(`${outputDir}/${label}-smaps-raw.txt`, data.raw);
}
// Save parsed summary (without raw to keep it small)
const summary: RssBreakdown = {
processMemoryUsage: data.processMemoryUsage,
rollup: data.rollup,
mappings: data.mappings,
};
await writeFile(`${outputDir}/${label}-rss-breakdown.json`, JSON.stringify(summary, null, 2));
// Log top mappings
if (data.mappings && data.mappings.length > 0) {
console.log(`[RSS] "${label}" breakdown (top 10 by RSS):`);
for (const m of data.mappings.slice(0, 10)) {
console.log(` ${m.rssMB.toFixed(1)} MB ${m.name} (${m.count} mappings)`);
}
}
if (data.rollup) {
console.log(
`[RSS] "${label}" rollup: RSS=${data.rollup.RssMB ?? '?'} MB, ` +
`Anon=${data.rollup.AnonymousMB ?? '?'} MB, ` +
`Shared=${(data.rollup.Shared_CleanMB ?? 0) + (data.rollup.Shared_DirtyMB ?? 0)} MB`,
);
}
return summary;
} catch (error) {
console.warn(`[RSS] Failed to capture breakdown: ${(error as Error).message}`);
return null;
}
}
/**
* Diff two RSS breakdowns and return the top growers and new mappings.
*/
export function diffRssBreakdowns(baseline: RssBreakdown, final: RssBreakdown): RssBreakdownDiff {
const baselineRssMB = baseline.processMemoryUsage.rss;
const finalRssMB = final.processMemoryUsage.rss;
// Diff per-mapping RSS
const baseMap = new Map<string, number>();
if (baseline.mappings) {
for (const m of baseline.mappings) baseMap.set(m.name, m.rssMB);
}
const topGrowers: RssBreakdownDiff['topGrowers'] = [];
const topNew: RssBreakdownDiff['topNew'] = [];
if (final.mappings) {
for (const m of final.mappings) {
const baseRss = baseMap.get(m.name);
if (baseRss !== undefined) {
const delta = m.rssMB - baseRss;
if (delta > 0.5) {
topGrowers.push({
name: m.name,
baselineRssMB: baseRss,
finalRssMB: m.rssMB,
deltaMB: Math.round(delta * 10) / 10,
});
}
} else if (m.rssMB > 0.5) {
topNew.push({ name: m.name, rssMB: m.rssMB });
}
}
}
topGrowers.sort((a, b) => b.deltaMB - a.deltaMB);
topNew.sort((a, b) => b.rssMB - a.rssMB);
// Diff rollup categories
let rollupDiff: RssBreakdownDiff['rollupDiff'] = null;
if (baseline.rollup && final.rollup) {
rollupDiff = {};
const allKeys = new Set([...Object.keys(baseline.rollup), ...Object.keys(final.rollup)]);
for (const key of allKeys) {
const b = baseline.rollup[key] ?? 0;
const f = final.rollup[key] ?? 0;
if (Math.abs(f - b) > 0) {
rollupDiff[key] = { baseline: b, final: f, delta: f - b };
}
}
}
return {
baselineRssMB,
finalRssMB,
deltaRssMB: finalRssMB - baselineRssMB,
topGrowers,
topNew,
rollupDiff,
};
}