replit-load-scale

# Replit Load & Scale ## Overview Load testing, scaling strategies, and capacity planning for Replit deployments. Covers Autoscale behavior tuning, Reserved VM right-sizing, cold start optimization, database connection scaling, and capacity benchmarking. ## Prerequisites - Replit app deployed (Autoscale or Reserved VM) - Load testing tool: k6, autocannon, or curl - Health endpoint implemented ## Replit Scaling Model | Deployment Type | Scaling Behavior | Cold Start | Best For | |-----------------|-----------------|------------|----------| | **Autoscale** | 0 to N instances based on traffic | Yes (5-30s) | Variable traffic | | **Reserved VM** | Fixed resources, always-on | No | Consistent traffic | | **Static** | CDN-backed, infinite scale | No | Frontend assets | ## Instructions ### Step 1: Baseline Benchmark ```bash # Quick benchmark with autocannon (built into Node.js ecosystem) npx autocannon -c 10 -d 30 https://your-app.replit.app/health # -c 10: 10 concurrent connections # -d 30: 30 seconds duration # Output shows: # - Requests/sec # - Latency (p50, p95, p99) # - Throughput (bytes/sec) # - Error count ``` ### Step 2: Load Test with k6 ```javascript // load-test.js — comprehensive Replit load test import http from 'k6/http'; import { check, sleep } from 'k6'; import { Rate, Trend } from 'k6/metrics'; const errorRate = new Rate('errors'); const coldStartTrend = new Trend('cold_start_duration'); export const options = { stages: [ { duration: '1m', target: 5 ...