How to increase the number of processing HTTP requests?

Question

I have ASP.NET Web API app (backend for mobile) published on Azure. Most of requests are lightweight and processed fast. But every client makes a lot of requests and do it rapidly on every interaction with mobile application.

The problem is that web application can't process even small (10/sec) amount of requests. Http queue growth but CPU doesn't.

I ran load testing with 250 requests/second and avg response time growth from ~200ms to 5s.

Maybe problem in my code? Or it's hardware restrictions? Can I increase count of processed requests at one time?

Answer 1

First it really matters what instances do you use (specially if you use small and extra small instances), how many instances do you use - dont expect too much from 1 core and 2Gb RAM on server.

Use caching (WebApi.OutputCache.V2 to decrease servers processing efforts, Azure Redis Cache as fast cache storage), Database also can be a bottleneck.

If you`ll have same results after adding both more instances to server and caching - then you should take a look at your code and find bottlenecks there.

And thats only general recommendatins, there is no code in a question.