What is the rationale for having the warm spares? If you're already able to spin up new VMs within an HTTP request, that seems pretty fast. Is the extra complexity just to make that path even faster?
The "warm spare" isn't running, but it's pre-loaded onto a particular worker. The slowest part of starting an app from scratch is checkout out the container; "warming up" the worker with the "spare" machine eliminates that.
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What is the rationale for having the warm spares? If you're already able to spin up new VMs within an HTTP request, that seems pretty fast. Is the extra complexity just to make that path even faster?
The "warm spare" isn't running, but it's pre-loaded onto a particular worker. The slowest part of starting an app from scratch is checkout out the container; "warming up" the worker with the "spare" machine eliminates that.