Fly can do this without the new Machines functionality, it's a big selling point for them.
You set a min and max number of VMs to run. Set the watermark for users per machine. And they automatically scale up and down depending on the number of connections. It will even figure out where in the world all the connections are coming from, and spin up the new VM in a region near to them.
So if your video encoding was requested via HTTP(S) connections then this would be trivial.
You set a min and max number of VMs to run. Set the watermark for users per machine. And they automatically scale up and down depending on the number of connections. It will even figure out where in the world all the connections are coming from, and spin up the new VM in a region near to them.
So if your video encoding was requested via HTTP(S) connections then this would be trivial.
https://fly.io/docs/reference/scaling/#autoscaling