3 ms·

Is this because runtimes optimize for the CPU stepping during startup? How many people actually rely on moving workloads around as live processes without restar

Is this because runtimes optimize for the CPU stepping during startup? How many people actually rely on moving workloads around as live processes without restarting? I thought the industry had settled on "cattle, not pets" and letting instances appear and die as long as a quorum is maintained.

AdamJacobMuller 7y ago
> cattle, not pets People running VMWare don't even consider that. Most people have that as a goal which they aren't achieving (and that's fine). I would doubt there's any company in existence actually attaining that goal.
- erik_seaberg 7y ago
  I admit I haven't had occasion to use VMware for a decade. Different world, I guess.
  - AdamJacobMuller 7y ago
    I don't use it either, but, it's The Thing in some IT departments. It does offer some amazing capabilities for making old legacy applications that were never designed to have any semblance of failover or redundancy or disaster recovery operate in impressively resilient ways. You also pay for the privilege.
kazen44 7y ago
the main reason you cannot mix CPU architectures in VMware systems is because doing a vmotion with zero downtime is impossible without major performance hits. having clusters with the same configuration is useful because it allows vcenter to migrate virtual machines to another hardware host without any downtime on the VM's part. you can read more about this here: https://blogs.vmware.com/vsphere/2019/07/the-vmotion-process-under-the-hood.html https://blogs.vmware.com/vsphere/2019/07/the-vmotion-process...
kortilla 7y ago
The people following the latest hype have definitely settled on that. The 95% of the tech world outside of the bubble just barely got comfortable with virtualizing everything in VMs about 5 years ago. The people that wrote the software enterprises are using absolutely did not design in scenarios where you can lose nodes arbitrarily without interruption.

AdamJacobMuller 7y ago

> cattle, not pets People running VMWare don't even consider that. Most people have that as a goal which they aren't achieving (and that's fine). I would doubt there's any company in existence actually attaining that goal.

erik_seaberg 7y ago
I admit I haven't had occasion to use VMware for a decade. Different world, I guess.
- AdamJacobMuller 7y ago
  I don't use it either, but, it's The Thing in some IT departments. It does offer some amazing capabilities for making old legacy applications that were never designed to have any semblance of failover or redundancy or disaster recovery operate in impressively resilient ways. You also pay for the privilege.

kazen44 7y ago

the main reason you cannot mix CPU architectures in VMware systems is because doing a vmotion with zero downtime is impossible without major performance hits. having clusters with the same configuration is useful because it allows vcenter to migrate virtual machines to another hardware host without any downtime on the VM's part. you can read more about this here: https://blogs.vmware.com/vsphere/2019/07/the-vmotion-process-under-the-hood.html https://blogs.vmware.com/vsphere/2019/07/the-vmotion-process...

kortilla 7y ago

The people following the latest hype have definitely settled on that. The 95% of the tech world outside of the bubble just barely got comfortable with virtualizing everything in VMs about 5 years ago. The people that wrote the software enterprises are using absolutely did not design in scenarios where you can lose nodes arbitrarily without interruption.