run multiple server threads

entrypoint.spec.js

@@ -1,18 +1,19 @@
 import { expect } from 'chai'
 import isSvg from 'is-svg'
 import got from './core/got-test-client.js'
+import startServer from './server.js'
 
-let serverModule
+let server
 before(async function () {
   this.timeout('30s')
   // remove args coming from mocha
   // https://github.com/badges/shields/issues/3365
   process.argv = []
-  serverModule = await import('./server.js')
+  server = await startServer()
 })
 
 after('shut down the server', async function () {
-  await serverModule.server.stop()
+  await server.stop()
 })
 
 it('should render a badge', async function () {

server.js

@@ -1,3 +1,5 @@
+import cluster from 'cluster'
+import { availableParallelism } from 'os'
 import fs from 'fs'
 import path from 'path'
 import { fileURLToPath } from 'url'
@@ -60,6 +62,25 @@ if (fs.existsSync(legacySecretsPath)) {
   )
   process.exit(1)
 }
-export const server = new Server(config)
 
-await server.start()
+async function startServer() {
+  const server = new Server(config)
+  await server.start()
+  return server
+}
+
+export default startServer
+
+const numCPUs = availableParallelism()
+if (process.env.NODE_CONFIG_ENV !== 'test') {
+  if (cluster.isPrimary) {
+    console.log(`Primary ${process.pid} is running`)
+
+    for (let i = 0; i < numCPUs; i++) {
+      cluster.fork()
+    }
+  } else {
+    await startServer()
+    console.log(`Worker ${process.pid} started`)
+  }
+}