I plan to do this in the near future once my GCP credits are used up (18 months of credits left).
My plan is to temporarily shift to dedicated hardware through a service like Hetzner to evaluate what kind of hardware I need. I can simply redirect a fraction of the traffic and extrapolate. Since this is elastic there will be no upfront costs, but I can play around with different sizes. Once I'm happy with my estimate, buy real hardware and move the rest over.
At least that's the plan. I don't think you can do much more than an educated guess and I think this will be as close as I can get.
Gee... if only there was a service where you could spin up machines on demand. (joke)
I kinda worked backwards from the cost. I ran the business for a year on Azure but each 'sample' of the resample took about 2 mins so it precluded any near real-time analysis. I ported the kernel to a GPU locally using python/numba and it ran in about 10 seconds and that was enough to seal-the-deal.
From there, I spec-ed out a GPU server and then machines that matched each role in my environment. I decided I was willing to spend $50K and just started loading up the machines.
