[anurag]

This is a big deal because you can now run Firecracker/other microVMs in an AWS VM instead of expensive AWS bare-metal instances.

GCP has had nested virtualization for a while.

[direwolf20]

You can use an expensive AWS VM instead of an expensive AWS bare–metal image. Does anyone realise how expensive AWS is, even in the best case?

[PunchyHamster]

It is expensive. But the point where it stops being expensive is far above most companies use case. If you're paying less than a developers salary for hosting you most likely won't see all that many benefits from moving.

Renting a server from cheaper hosting providers can be massive savings but you now need to re-invent all of the AWS APIs you use or might use and it's big CAPEX time investment. And any new feature you need, whether that's queue, mail gateway or thousand other APIs need to be deployed and managed first before you can even start testing.

It's less work now than it was before just due to amount of tools there are to automate it but it's still more work that you could be spending on improving your product.

[Twirrim]

OCI supports it with Intel. I know it works with AMD, but we don't officially support that so far as I'm aware. The performance hit on AMD is bigger than Intel, last I looked.

[iJohnDoe]

Was hoping this comment would be here. Firecracker and microVMs are good use-case. Also, being able to simply test and develop is a nice to have.

Nested virtualization can mean a lot of things. Not just full VMs.

[HumanOstrich]

> Firecracker and microVMs are good use-case.

Good use-case for what?

[parhamn]

whats the ~ perf hit of something like this?

[largbae]

Nowadays nested just wastes the extra operating system overhead and I/O performance if your VM doesn't have paravirtualization drivers installed. CPUs all have hardware support.

[otterley]

As a practical matter, anywhere from 5-15%.

[firesteelrain]

Azure has had nested virt available for a while too. I used to run HyperV in cloud

[whopdrizzard]

Azure has recently announced "direct virtualization", which is a sort of logical nesting, in which users can sub-partition their L1 VMs into virtual L2 VMs that are technically siblings.

https://techcommunity.microsoft.com/blog/azurecompute/scalin...

(I work there)