3 ms·

> - Disadvantages: speed Nuh? Of starting, sure. Of running? A margin of error.

• nailer 7y ago
  Running an app inside a container on bare metal is way faster than running an app in a VM on bare metal. - Containers in this case: userspace on kernel on hardware - VMs in this case: userspace on kernel on virtual hardware on kernel on hardware. There are very fast VMs (the Firecracker MIcroVM) but they're not in popular use.
  • notyourday 7y ago
    You are hopelessly out of date. VMs are not Xen with emulation. Neither are they the original VMware. Nor are they QEMU without acceleration. VMs are qemu-system-x86_64 -machine accel=kvm or whatever is the platform specific way to run a VM under a hypervisor. This has been the case since hypervisors showed up on the scene, aka right after what was the predecessor of Virtuozzo
    • nailer 7y ago
      Xen was never an emulator. That's technically incorrect. Not does the definition of VM change because of hardware acceleration. That's also technically incorrect.
      • notyourday 7y ago
        It should have been VMware with emulation, not Xen. You are correct The overhead of running a VM absolutely changes depending on whether it is a type 1 hypervisor or a type 2 hypervisor or if the runner/monitor supports acceleration. You can run a VM with QEMU without accel=kvm and it will be dog slow. Try it.
        • nailer 7y ago
          I know re qemu and hypervisor types. VMware was never an emulator, but TBH we agree more than we disagree - have a good weekend