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You don’t understand what immutable distros are for. Imagine you need to upgrade 500k machines and your options are either run an agent that has to make the sam

You don’t understand what immutable distros are for. Imagine you need to upgrade 500k machines and your options are either run an agent that has to make the same changes 500k times and hopefully converges onto the same working state no matter the previous state of the machines its running on, or you pull a well tested image that can be immediately rolled back to the previous image if something goes wrong. Saying it’s just about integrity is like saying docker images are just about integrity… they absolutely are not. They give you atomic units of deployment, the ability to run the same thing in prod as you do in dev. Many other benifits.

bezier-curve 2y ago
Is immutability's benefits not the "integrity" of a system? This seems pedantic.
- mrkeen 2y ago
  The comment was reaffirming immutability's benefits, against the previous comment which said traditional packaging provides a better tradeoff.
  - __david__ 2y ago
    The original comment was not about traditional packaging, it was about Nix which is different (and immutable in its own way).
IshKebab 2y ago
> and hopefully converges onto the same working state no matter the previous state of the machines its running on Isn't that exactly the point of NixOS?
- flakes 2y ago
  I think the point they’re getting at, is that there are typically a lot of delta states in between pre-upgrade and post-upgrade states when using package managers. With immutable distros, the upgrade becomes more of an atomic operation than what is offered by more incremental package manager updates. It also means you can completely leave out the package manager from the target machines, as it’s only used to bootstrap creation of the single deployable unit. Implementing that bootstrapping step is where nix and friends are helpful in this setup.
  - josephg 2y ago
    This sort of atomic change should be something the filesystem provides. I think it’s crazy that databases have had mechanisms for transactions and rollbacks since the 70s and they’re still considered a weird feature on a filesystem. There’s all sorts of ways a feature like that could provide value. Adding atomicity to system package managers would be a large, obvious win.
    - IshKebab 2y ago
      I agree. The fact that we're still doing atomic writes by renaming files is laughable. That's also pretty much the only atomic thing you can do. I think the issue is the posix filesystem API. Nobody writes better filesystems because no software would use the new features, and no software supports fancier filesystem features because the posix API doesn't expose them. It'll probably take someone like Apple or Google to fix this. Similar to 16kB pages.
      - jodrellblank 2y ago
        > Nobody writes better filesystems People tried: https://en.wikipedia.org/wiki/Transactional_NTFS https://en.wikipedia.org/wiki/Transactional_NTFS and https://learn.microsoft.com/en-gb/windows/win32/fileio/deprecation-of-txf?redirectedfrom=MSDN https://learn.microsoft.com/en-gb/windows/win32/fileio/depre... "[Transactional NTFS (TxF)] was introduced with Windows Vista as a means to introduce atomic file transactions to Windows. It allows for Windows developers to have transactional atomicity for file operations in transactions with a single file, in transactions involving multiple files, and in transactions spanning multiple sources – such as the Registry (through TxR), and databases (such as SQL). While TxF is a powerful set of APIs, there has been extremely limited developer interest in this API platform since Windows Vista primarily due to its complexity and various nuances which developers need to consider as part of application development. As a result, Microsoft is considering deprecating TxF APIs in a future version of Windows"
        mkl 2y ago
        And even more ambitiously, WinFS: https://en.wikipedia.org/wiki/WinFS https://en.wikipedia.org/wiki/WinFS
shatsky 2y ago
>hopefully converges onto the same working state >Saying it’s just about integrity is like saying docker images are just about integrity >atomic units of deployment, the ability to run the same thing in prod as you do in dev In my understanding, integrity is exactly about software being in certain known correct state, including absence of anything which is not part of that state. Of course integrity of parts of software system like individual packages contents does not make it really reliable when the whole system does not have it. NixOS has it and also allows to "run the same thing"

bezier-curve 2y ago

Is immutability's benefits not the "integrity" of a system? This seems pedantic.

mrkeen 2y ago
The comment was reaffirming immutability's benefits, against the previous comment which said traditional packaging provides a better tradeoff.
- __david__ 2y ago
  The original comment was not about traditional packaging, it was about Nix which is different (and immutable in its own way).

IshKebab 2y ago

> and hopefully converges onto the same working state no matter the previous state of the machines its running on Isn't that exactly the point of NixOS?

flakes 2y ago
I think the point they’re getting at, is that there are typically a lot of delta states in between pre-upgrade and post-upgrade states when using package managers. With immutable distros, the upgrade becomes more of an atomic operation than what is offered by more incremental package manager updates. It also means you can completely leave out the package manager from the target machines, as it’s only used to bootstrap creation of the single deployable unit. Implementing that bootstrapping step is where nix and friends are helpful in this setup.
- josephg 2y ago
  This sort of atomic change should be something the filesystem provides. I think it’s crazy that databases have had mechanisms for transactions and rollbacks since the 70s and they’re still considered a weird feature on a filesystem. There’s all sorts of ways a feature like that could provide value. Adding atomicity to system package managers would be a large, obvious win.
  - IshKebab 2y ago
    I agree. The fact that we're still doing atomic writes by renaming files is laughable. That's also pretty much the only atomic thing you can do. I think the issue is the posix filesystem API. Nobody writes better filesystems because no software would use the new features, and no software supports fancier filesystem features because the posix API doesn't expose them. It'll probably take someone like Apple or Google to fix this. Similar to 16kB pages.
    - jodrellblank 2y ago
      > Nobody writes better filesystems People tried: https://en.wikipedia.org/wiki/Transactional_NTFS https://en.wikipedia.org/wiki/Transactional_NTFS and https://learn.microsoft.com/en-gb/windows/win32/fileio/deprecation-of-txf?redirectedfrom=MSDN https://learn.microsoft.com/en-gb/windows/win32/fileio/depre... "[Transactional NTFS (TxF)] was introduced with Windows Vista as a means to introduce atomic file transactions to Windows. It allows for Windows developers to have transactional atomicity for file operations in transactions with a single file, in transactions involving multiple files, and in transactions spanning multiple sources – such as the Registry (through TxR), and databases (such as SQL). While TxF is a powerful set of APIs, there has been extremely limited developer interest in this API platform since Windows Vista primarily due to its complexity and various nuances which developers need to consider as part of application development. As a result, Microsoft is considering deprecating TxF APIs in a future version of Windows"
      - mkl 2y ago
        And even more ambitiously, WinFS: https://en.wikipedia.org/wiki/WinFS https://en.wikipedia.org/wiki/WinFS

shatsky 2y ago

>hopefully converges onto the same working state >Saying it’s just about integrity is like saying docker images are just about integrity >atomic units of deployment, the ability to run the same thing in prod as you do in dev In my understanding, integrity is exactly about software being in certain known correct state, including absence of anything which is not part of that state. Of course integrity of parts of software system like individual packages contents does not make it really reliable when the whole system does not have it. NixOS has it and also allows to "run the same thing"