Custom limits

index.js
export default {
 async fetch(request, env) {
   try {
     // parse the URL, read the subdomain
     let workerName = new URL(request.url).host.split('.')[0];
     let userWorker = env.dispatcher.get(
       workerName,
       {},
       {// set limits
         limits: {cpuMs: 10, subRequests: 5}
       }
     );
     return await userWorker.fetch(request);
   } catch (e) {
     if (e.message.startsWith('Worker not found')) {
       // we tried to get a worker that doesn't exist in our dispatch namespace
       return new Response('', { status: 404 });
     }
      return new Response(e.message, { status: 500 });
   }
 },
};