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I’ve always felt BSDs are way underrated, and Dragonfly being underrated the most. Dragonfly has some really innovative features: - H2 - virtual kernels - h

I’ve always felt BSDs are way underrated, and Dragonfly being underrated the most. Dragonfly has some really innovative features: - H2 - virtual kernels - how it achieves SMP with no locking - and much more

viraptor 4y ago
That's the kernel memory allocator in SMP being lockless, right? (https://www.dragonflybsd.org/features/ https://www.dragonflybsd.org/features/) You still can't get around locks for many shared resources, especially hardware ones.
- jpfr 4y ago
  Linus Torvalds says that the RCU mechanism in the kernel making filesystem access lockless is one of the greatest achievements in Linux.
- black7375 4y ago
  wow LWKT and HAMMER2 look good.
xvilka 4y ago
Too bad it's only x86(64)-compatible. Even port to ARMv8 (Raspberry Pi especially) could help to increase the interest to this OS.
- snvzz 4y ago
  Today, I'd instead look at 64bit RISC-V, as that's where computing seems to be going.
  - nix23 4y ago
    Really? Please show me a production server based on RISC-V, dont get me wrong i would love that, but reality being reality ARM is something atm..and not RISC-V...nor POWER...hmhmmm..
    - snvzz 4y ago
      The first ones (e.g. based on Ventana's Veyron) are due H2 this year. ARM has some cursory presence in the datacenter today, but I wouldn't bet on ARM being more predominant than RISC-V there by 2025. If anything, migration of servers to ARM has halted because decision makers can read the writing on the wall.
      - nix23 4y ago
        >If anything, migration of servers to ARM has halted because decision makers can read the writing on the wall. I see the opposite here... >but I wouldn't bet on ARM being more predominant than RISC-V there by 2025. Sure Apple and all Smartphones will change to RISC-V, look i would love to believe that, it's just not the reality. But if you talk about microcontroller'ish stuff, then you are probably right that risv will be more dominant in 2025.
yjftsjthsd-h 4y ago
> virtual kernels I'm pretty sure that's equivalent to netbsd's rump kernels and Linux's UML (user mode Linux), no? Certainly a good feature, and something I were saw wider use, but hardly unique.
- potatoalienof13 4y ago
  The NetBSD rumpkernel allows for running individual drivers in userspace, while UML and vkernel are both geared towards running full kernels. UML and vkernel both look pretty similar to me though.
  - yjftsjthsd-h 4y ago
    That's true, but that just means that rump kernels took the microkernel approach and make you do it piecemeal; I still think it counts as a different side of the same coin.

viraptor 4y ago

That's the kernel memory allocator in SMP being lockless, right? (https://www.dragonflybsd.org/features/ https://www.dragonflybsd.org/features/) You still can't get around locks for many shared resources, especially hardware ones.

jpfr 4y ago
Linus Torvalds says that the RCU mechanism in the kernel making filesystem access lockless is one of the greatest achievements in Linux.
black7375 4y ago
wow LWKT and HAMMER2 look good.

xvilka 4y ago

Too bad it's only x86(64)-compatible. Even port to ARMv8 (Raspberry Pi especially) could help to increase the interest to this OS.

snvzz 4y ago
Today, I'd instead look at 64bit RISC-V, as that's where computing seems to be going.
- nix23 4y ago
  Really? Please show me a production server based on RISC-V, dont get me wrong i would love that, but reality being reality ARM is something atm..and not RISC-V...nor POWER...hmhmmm..
  - snvzz 4y ago
    The first ones (e.g. based on Ventana's Veyron) are due H2 this year. ARM has some cursory presence in the datacenter today, but I wouldn't bet on ARM being more predominant than RISC-V there by 2025. If anything, migration of servers to ARM has halted because decision makers can read the writing on the wall.
    - nix23 4y ago
      >If anything, migration of servers to ARM has halted because decision makers can read the writing on the wall. I see the opposite here... >but I wouldn't bet on ARM being more predominant than RISC-V there by 2025. Sure Apple and all Smartphones will change to RISC-V, look i would love to believe that, it's just not the reality. But if you talk about microcontroller'ish stuff, then you are probably right that risv will be more dominant in 2025.

yjftsjthsd-h 4y ago

> virtual kernels I'm pretty sure that's equivalent to netbsd's rump kernels and Linux's UML (user mode Linux), no? Certainly a good feature, and something I were saw wider use, but hardly unique.

potatoalienof13 4y ago
The NetBSD rumpkernel allows for running individual drivers in userspace, while UML and vkernel are both geared towards running full kernels. UML and vkernel both look pretty similar to me though.
- yjftsjthsd-h 4y ago
  That's true, but that just means that rump kernels took the microkernel approach and make you do it piecemeal; I still think it counts as a different side of the same coin.