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LightVM – A new virtualization solution based on Xen

cnp.neclab.eu

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Re: LightVM – A new virtualization solution based on Xen

#21

Post by nickik »

citrin_ru wrote: post #17

> We achieve lightweight VMs by using unikernels One problems with unikernels is a lack of debugging/tracing tools (like Dtrace/eBPF): https://www.joyent.com/blog/unikernels-are-unfit-for-product...

That blog post is pretty crappy.

See discussions here: https://news.ycombinator.com/item?id=10953766

Re: LightVM – A new virtualization solution based on Xen

#22

Post by detaro »

weberc2 wrote: post #19
detaro wrote: post #13

Earlier quoted context omitted.

No, not unikernels. They use unikernels and small linux builds for examples to show their improvement of Xen itself.

> We achieve lightweight VMs by using unikernels for specialized applications Unikernels appear to be part of the solution...

Yes, but it's more "we made Xen faster so you can use unikernels even better". Unikernels aren't the new thing here.

Re: LightVM – A new virtualization solution based on Xen

#24

Post by Philipp__ »

weberc2 wrote: post #16
lbotos wrote: post #12

Earlier quoted context omitted.

I haven't been on the server side in a while, but 1) isn't Xen falling out of favor and 2) is docker boot speed a big problem?

Boot speed is a big selling point for Docker, but Docker's isolation story is poorer than a VM. If you can make a VM boot as quickly as Docker while preserving isolation, then Docker loses a big selling point.

It’s called Zones (on illumos, prev. on Solaris)

Re: LightVM – A new virtualization solution based on Xen

#25

Post by citrin_ru »

nickik wrote: post #21
citrin_ru wrote: post #17

> We achieve lightweight VMs by using unikernels One problems with unikernels is a lack of debugging/tracing tools (like Dtrace/eBPF): https://www.joyent.com/blog/unikernels-are-unfit-for-product...

That blog post is pretty crappy. See discussions here: https://news.ycombinator.com/item?id=10953766

The blog post has some flawed arguments, but still there is almost no observability/tracing tools for unikernels.

Re: LightVM – A new virtualization solution based on Xen

#26

Post by contingencies »

Great job and nice to see Romania featuring in the news!

To those who just spent the last two years retraining your teams and retooling your infrastructure explicitly for docker (who may show up in this thread embracing and enhancing with a large marketing budget shortly), do take this opportunity to learn the architectural and management/maintenance value of abstraction. ;)

Re: LightVM – A new virtualization solution based on Xen

#27

Post by nickik »

citrin_ru wrote: post #25
nickik wrote: post #21

Earlier quoted context omitted.

That blog post is pretty crappy. See discussions here: https://news.ycombinator.com/item?id=10953766

The blog post has some flawed arguments, but still there is almost no observability/tracing tools for unikernels.

Some do, some don't. But to link to this as the 'super-argument' every-time somebody mentioned unikernels is pointless and wrong.

Its also simply not relevant for many cases.

Re: LightVM – A new virtualization solution based on Xen

#28

Post by bmitch3020 »

VM's tend to lose the overlay layered filesystem which can dramatically reduce disk usage. Having the filesystem reset to a clean state for every new container is a huge feature of containers. And VM's tend to need predefined dedicated resources for things like memory. A process in a container would only allocate memory when it needs and can free up for other processes to use. It's not all about the startup speed.

That said, VM's have their place, and docker has the option to switch out backends. It's entirely possible to replace runc with some other tool that starts VM's instead of containers. (That's already happening today with Windows containers.)

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