4 ms·

So you mean like... NTOSKRNL et al essentially retrofitted to run in a kind of userspace? Nice. I don't expect that kind of thing to ever leave a research env

by i336_ 9y ago

So you mean like... NTOSKRNL et al essentially retrofitted to run in a kind of userspace? Nice. I don't expect that kind of thing to ever leave a research environment though. It would mess with too many people's heads and give people too many ideas of running bare-metal kernels other than NT. Now I think about it, I realize the reason why HW virtualization really took off is because it let vendors keep their operating systems as actual operating systems in the traditional sense of the word, making for fewer legal issues (among many other reasons). Also, I thought Xen was essentially just a super-thin layer to kickstart VT-x/AMD-V. I didn't know it could do anything else. In fact, I thought there was only emulation and hardware-assisted virtualization. Is there a middle ground I'm not aware of?

my123 9y ago
Yes. It's paravirtualization. Oh, Drawbridge is full NT in user-space, is in production now for SQL Server on Linux, but Dk (Drawbridge) is much newer. :)
- i336_ 9y ago
  TIL. That's really cool. Now I'm wondering if there are any small fully-paravirtualized hypervisors and guests I can play with. I guess Linux's support for various forms of I/O acceleration is more or less it. I didn't know Drawbridge was that amazing - that's incredible. And now I'm starting to understand Microsoft's vision: they have WSL to get Linux infrastructure onto Windows, and Dk to get selected Windows infrastructure onto Linux. Impressive. But now I think about it that way, I know Dk will only ever be an internal framework - if that got released we'd basically have "perfect Wine" and it would allow quite a few too many applications to move off of NT.
  - my123 9y ago
    WSL uses Drawbridge picoprocesses internally by the way. :) The Drawbridge NTUM(User-Mode NT kernel) is maintained as NT 6.2 (Windows 8) which is new enough for almost all purposes - except modern Windows apps.

by i336_ 9y ago

my123 9y ago

Yes. It's paravirtualization. Oh, Drawbridge is full NT in user-space, is in production now for SQL Server on Linux, but Dk (Drawbridge) is much newer. :)

i336_ 9y ago
TIL. That's really cool. Now I'm wondering if there are any small fully-paravirtualized hypervisors and guests I can play with. I guess Linux's support for various forms of I/O acceleration is more or less it. I didn't know Drawbridge was that amazing - that's incredible. And now I'm starting to understand Microsoft's vision: they have WSL to get Linux infrastructure onto Windows, and Dk to get selected Windows infrastructure onto Linux. Impressive. But now I think about it that way, I know Dk will only ever be an internal framework - if that got released we'd basically have "perfect Wine" and it would allow quite a few too many applications to move off of NT.
- my123 9y ago
  WSL uses Drawbridge picoprocesses internally by the way. :) The Drawbridge NTUM(User-Mode NT kernel) is maintained as NT 6.2 (Windows 8) which is new enough for almost all purposes - except modern Windows apps.