Maxing out your CPU and networking. If you're there, you'll be running many hosts under load balancers. Be it cloud instances or physical machines. Here you have no need for containers. Web servers and backend apps are capable of multi threading.

You can't just "enable multi threading" in a varietal ecology of software applications and contexts.

Also, this is not an argument _against_ containerization. You make no argument or show any evidence of performance benefits bare v. docker.

We max out our compute about 3% of the time, and run at about 10% load the rest of the time. It's a similar story for memory consumption. And we run this multitenanted, where the max doesn't overlap for different tenants. And we can't move our customer data out of our data centre, so we can't use cloud elastic compute.

It's in this kind of a world that elastic compute provided by a cluster scheduler with efficient packing looks really appealing. And our jobs, while meaty in time and space, are stateless once the initial data is poured in, up until the results pop out - they are big functions, basically. Good match for a stateless container.

So k8s looks quite attractive.

That's ... not even wrong.