What a ridiculous statement. Splitting a single process into N processes with no shared memory multiples startup memory by N. It takes a much beefier system to run 8 JVMs than one. The same goes for 8 Python processes. Matters are worse on a VM, which you probably are since basically every shop out there issues developers a Windows or OSX machine. Or maybe you don't have "weak tooling," as you put it, and everything's containerized, using even more resources.
"Splitting a single process into N processes with no shared memory multiples startup memory by N. It takes a much beefier system to run 8 JVMs than one. The same goes for 8 Python processes."
I agree, but I haven't seen the amount of memory ever being a limiting factor when running multiple microservices on a local developer machine. I'd estimate that you can run at least 50 JVM, Python and Node.js processes on a typical single machine, and most applications consisting of microservices have 50 or less microservices.
> I'd estimate that you can run at least 50 JVM, Python and Node.js processes on a typical single machine
Unless someone has convinced you that Spring is the right way to build microservices, in which case you're going to need a gigabyte per instance, and most people won't be able to run 50 on a typical machine. I worked on a project like that, and our beefy iMacs really laboured to bring up ten services.
It's not just the runtime. Each Python process will redundantly import modules. The same goes for libraries in a Java project. It definitely adds up, and I have seen memory usage be an issue, particularly on VMs.
