4 ms·

systemd is like a second kernel in user-space.

by zimbatm 13y ago

mmphosis 13y ago
and, launchd is like a second mach kernel at a higher level. https://developer.apple.com/library/mac/documentation/Darwin/Conceptual/KernelProgramming/Mach/Mach.html https://developer.apple.com/library/mac/documentation/Darwin...
- teacup50 13y ago
  Except for the part where launchd doesn't implement anything other than traditional process/service launch and termination, and doesn't violate the layering boundaries between system components. In a launchd system, there's absolutely no dependency on launchd by userspace software.
zanny 13y ago
Which should be good. If the OPs arguments about how dangerous it is to empower and stuff a lot of functionality into pid 1, think of how running in kernel mode on a cpu gives you power when your code is in the kernel proper. So moving functionality out of kernel mode and into user mode is great. The only steps after that are moving as much functionality as possible to the user, and then to nobody. We do trend towards minimum permissions for the sake of security for a reason.
- dalias 13y ago
  Functionality is not being moved out of the kernel and into userspace. It's being moved out of legacy freedesktop.org components (hald, ConsoleKit, PolicyKit, etc.) and into PID 1. Where should it be moved to? /dev/null.
  - nona 13y ago
    I think you need to look a bit more closely at what's actually going into PID 1. See for example: http://people.debian.org/~stapelberg/docs/systemd-dependencies.html http://people.debian.org/~stapelberg/docs/systemd-dependenci... I don't see any logind/hostnamed/journald or any of that stuff in PID1.
  - Jasper_ 13y ago
    hald has been dead forever. PolicyKit is not being moved into systemd, nor is it getting systemd integration? How do you want to replace ConsoleKit/logind? What should handle session management?
    - teacup50 13y ago
      Something other than your init system. Not even Apple's launchd has the kinds of idiotic layering violations that systemd is full of.
      - Jasper_ 13y ago
        Well, you'll be happy to learn that logind is a separate process entirely.
        teacup50 13y ago
        Layering violations don't only happen within the process level.

systemd is like a second kernel in user-space.

by zimbatm 13y ago

systemd is like a second kernel in user-space.

and, launchd is like a second mach kernel at a higher level. https://developer.apple.com/library/mac/documentation/Darwin/Conceptual/KernelProgramming/Mach/Mach.html https://developer.apple.com/library/mac/documentation/Darwin...

teacup50 13y ago
Except for the part where launchd doesn't implement anything other than traditional process/service launch and termination, and doesn't violate the layering boundaries between system components. In a launchd system, there's absolutely no dependency on launchd by userspace software.

zanny 13y ago

Which should be good. If the OPs arguments about how dangerous it is to empower and stuff a lot of functionality into pid 1, think of how running in kernel mode on a cpu gives you power when your code is in the kernel proper. So moving functionality out of kernel mode and into user mode is great. The only steps after that are moving as much functionality as possible to the user, and then to nobody. We do trend towards minimum permissions for the sake of security for a reason.

dalias 13y ago
Functionality is not being moved out of the kernel and into userspace. It's being moved out of legacy freedesktop.org components (hald, ConsoleKit, PolicyKit, etc.) and into PID 1. Where should it be moved to? /dev/null.
- nona 13y ago
  I think you need to look a bit more closely at what's actually going into PID 1. See for example: http://people.debian.org/~stapelberg/docs/systemd-dependencies.html http://people.debian.org/~stapelberg/docs/systemd-dependenci... I don't see any logind/hostnamed/journald or any of that stuff in PID1.
- Jasper_ 13y ago
  hald has been dead forever. PolicyKit is not being moved into systemd, nor is it getting systemd integration? How do you want to replace ConsoleKit/logind? What should handle session management?
  - teacup50 13y ago
    Something other than your init system. Not even Apple's launchd has the kinds of idiotic layering violations that systemd is full of.
    - Jasper_ 13y ago
      Well, you'll be happy to learn that logind is a separate process entirely.
      - teacup50 13y ago
        Layering violations don't only happen within the process level.