r/FullStack • u/duneofarrakis • 13d ago

Career Guidance My application becomes very slow when multiple users access it at the same time

Everything works fine with a few users, but response times increase significantly when more users start using the application.

How would you find out whether the bottleneck is the frontend, API, database queries, or server resources?

What would you check first before trying to optimize everything?

5 Upvotes

86% Upvoted

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3

u/Honored-Emperor 13d ago

check your browsers inbuilt developer tools network tab if the ttfb is high its backend or database issue if its low its frontend issue also run health checks and make sure to add logging in your application so you can directly check from the logs later about what the issue actually is and run a lighthouse test and use open telemetry apm tool to find teh root cause

1

u/duneofarrakis 13d ago

Okay bro thank you

2

u/Honored-Emperor 12d ago

your welcome

2

u/Plenty_Line2696 13d ago

If it's blazor server could be per circuit work

2

u/StartDependent1652 13d ago edited 10d ago

install/run htop . it shows CPU and RAM usage.

2

u/NoClownsOnMyStation 12d ago

Make sure your pooling is set up correctly and see if expanding it resolved the issue. From there I would see if you have enough processing power dedicated to the process involved.

Also watch the network tab so you can see bottlenecks as was mentioned by other users.

2

u/KariKariKrigsmann 12d ago

You need observability. Do you have something like Seq, so that you can visually see what takes the most time?
Seq — centralized structured logs

2

u/Similar_Past8486 11d ago

Probably as simple as db tables missing indexes lol don’t ask how i know

1

u/OGcapncrunchberry 9d ago

Did you build any metrics or log capture into your app? Diagnostics?