Software to simulate IO and network throughput?

I was wondering if there’s software out there where you can enter detail a system setup, down to the CPU, disks, etc…, multiple systems even, with network connections.

The point would be to generate theoretical IO speed and network speed.

Say you’ve got a modern server with loads of pcie lanes, fast server storage, network speed, CPU that can push all of it, etc… but you do backups to an old JBOD that’s just a set of HDD with no write cache(for theoretical purposes).

The idea would be that you could detail your setup and it would point out points of congestion and just theoretical limts. But also you could say that certain connections have limited speed and then it tells you what the effect is on all other operations.

Maybe you have a cluster of SQL servers on a bunch of different physical servers. Well, what’s the limits and where are they?

That’s the kind of thing I’m looking for.

It’s just an idea I had, nothing urgent or anything like that, just a thought I had.

Does anyone know of anything like this existing?