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Show HN: Smol machines – subsecond coldstart, portable virtual machines

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Re: Show HN: Smol machines – subsecond coldstart, portable virtual machines

#51
post #47
post #39

Earlier quoted context omitted.

What is the status of supporting live migration? That's the one feature of similar systems that always gets left out. I understand why: it's not a priority for "cloud native" workloads. The world, however, has work loads that are not cloud native, because that comes at a high cost, and it always will. So if you'd like a real value-add differentiator for your micro-VM platform (beyond what I believe you already have,)…

It helps if you offer a concrete use case, as in how large the heap is, what kinda of blackout period you can handle, and whether the app can handle all of it's open connections being destroyed, etc. The more an app can handle resetting some of it's own state, the easier LM is going to be to implement. If your workload jives with CRIU https://github.com/checkpoint-restore/criu you could do this already. By what I ass…

"Azure and GCP use LM behind the scenes"

As does OCI, and (relatively recently) AWS. That's a lot of votes.

Use case: some legacy database VM needs to move because the host needs maintenance, the database storage (as opposed to the database software) is on a iSCSI/NFS/NVMe-oF array somewhere, and clients are just smart enough to transparently handle a brief disconnect/reconnect (which is built-in to essentially every such database connection pool stack today.)

Use case: a web app platform (node/spring/django/rails/whatever) with a bunch of cached client state needs to move because the host needs maintenance. The developers haven't done all the legwork to make the state survive restart, and they'll likely never get time needed to do that. That's essentially the same use case as previous. It's also rampant.

Use case: a long running batch process (training, etc.) needs to move because reasons, and ops can't wait for it to stop, and they can't kill it because time==money. It's doesn't matter that it takes an hour to move because big heap, as long as the previous 100 hours isn't lost.

"as in how large the heap is"

That's an undecidable moving target, so let the user worry about it. Trust them to figure out what is feasible given the capabilities of their hardware and talent. They'll do fine if you provide the mechanism. I've been shuffling live VMs between hosts for 10+ years successfully, and Qemu/KVM has been capable of it for nearly 20, never mind VMware.

"CRIU"

Dormant, and still containers. Also, it's re-solving solved problems once you're running in a VM, but with more steps.

Re: Show HN: Smol machines – subsecond coldstart, portable virtual machines

#52

Hello, I'm building a replacement for docker containers with a virtual machine with the ergonomics of containers + subsecond start times. I worked in AWS previously in the container space + with firecracker. I realized the container is an unnecessary layer that slowed things down + firecracker was a technology designed for AWS org structure + usecase. So I ended up building a hybrid taking the best of containers with…

Hey this is super cool. I've been researching tech like this for my AI sandboxing solution, ended up with Lima+Incus: https://github.com/JanPokorny/locki My problem with microVMs was that they usually won't run docker / kubernetes, I work on apps that consist of whole kubernetes clusters and want the sandbox to contain all that. Does your solution support running k3s for example?

we will evaluate. I created this issue to track this: https://github.com/smol-machines/smolvm/issues/150

Really appreciate the feedback!

Re: Show HN: Smol machines – subsecond coldstart, portable virtual machines

#54
post #45
post #43

Earlier quoted context omitted.

Really appreciate the suggestion! By "live migration", do you mean keeping the existing files and migrate them elsewhere with the vm? Thanks

I mean making any given VM stop on host A and appear on host B; e.g. standard Qemu/KVM: virsh migrate --live GuestName DestinationURL This is feasible when network storage is available and useful when a host needs to be drained for maintenance.

I see. so right now smolvm can be stopped, and then "packed" (think of it as compressed), and restart on a different host. files in the disks are preserved, but memory snapshotting is still hard tbh

Re: Show HN: Smol machines – subsecond coldstart, portable virtual machines

#58
post #21

Earlier quoted context omitted.

With this approach I managed to get to sub-10ms start (to pid1), if you can accept a few constraints there's plenty of room! Though my version was only tested on Linux hosts

would be interested to see how you do it, how can I connect with you - emotionally?

Start with booze; always works :)

Re: Show HN: Smol machines – subsecond coldstart, portable virtual machines

#59

Hello, I'm building a replacement for docker containers with a virtual machine with the ergonomics of containers + subsecond start times. I worked in AWS previously in the container space + with firecracker. I realized the container is an unnecessary layer that slowed things down + firecracker was a technology designed for AWS org structure + usecase. So I ended up building a hybrid taking the best of containers with…

What percentage of this code was written by LLM/AI?
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