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Optimal Lab

DevOps · interactive

Containers vs virtual machines

Both run your app on someone else's hardware. A container shares the host kernel. A virtual machine boots a second operating system.

Press Start both to launch the same app each way, side by side.

Container

stopped

shares the host kernel

  1. 1

    An image is a stack of file layers, plus a command to run.

    Layers here: base files, libraries, your app. No second operating system.

  2. 2

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In production this takes about a second.

Virtual machine

stopped

boots its own operating system

  1. 1

    The hypervisor reserves CPU, memory, and a virtual disk.

    This is a computer made of software, sitting on the real one.

  2. 2

  3. 3

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  5. 5

In production this takes tens of seconds to minutes.

In production

Tools and technologies

Containers share one kernel; VMs boot a full guest OS — the tradeoff is the same on any cloud.

Not tied to one language — use these names when you search docs or design a system.