Renting by the slice

Sam’s spreadsheet from Act II guessed at processor, memory and disk. The cloud, it turns out, prices everything in three resources of its own, and they rhyme.

computeConcept · lights on your mapcomputeThe CPU and memory that perform work: the first of the cloud’s three foundational resources. Compute does the work. does the work: the CPU and memory from Act II, rented by the hour. storageConcept · lights on your mapstorageThe resource that preserves information: the second foundational resource. Storage remembers. remembers: the cabinet, rented by the gigabyte-month. And networkingConcept · lights on your mapnetworkingThe resource that carries requests, responses and data between systems: the third foundational resource. Networking connects. connects: the wiring from Act I, rented by the byte moved. Work, memory, movement. Every invoice the cloud has ever issued is some arrangement of those three lines.

The machine that is a file

What Traversal actually summons is a virtual machineConcept · lights on your mapvirtual machineA software-defined computer behaving like an independent machine: virtual processors, memory, disks, and network, its own operating system, backed by real shared hardware. The hardware is real; the boundaries are drawn in software.: a computer defined in software, carved out of a real machine in one of Friday’s buildings, wearing its own Linux and believing itself alone. The hardware is real. The boundaries are software. One physical machine in a rack hosts many virtual ones, each walled off from its neighbours, and Traversal’s entire backend has run on such machines since the first scene of this story without the distinction ever once mattering. That is how good the illusion is.

One running copy, created from a saved configuration, is an instanceConcept · lights on your mapinstanceOne running occurrence of a cloud resource configuration. Spin up an instance means create and start one; terminate means remove it. The cloud’s habit of treating machines as reproducible copies of a type rather than unique objects., and the word carries the cloud’s whole temperament. Machines stopped being individuals and became copies of a recipe: spin up thirty, terminate twenty-eight, no machine has a name anyone mourns. Sunday’s multiplication is exactly this, thirty instances of the tracking service’s recipe, summoned before dawn and dismissed by dinner.

Rentable machines are the bottom of a ladder. The next two rungs up, somebody else runs more and more of it for you, until at the top there is a server Traversal only meets two days a year.