Mastodawn

Passing thoughts on Universal Blue and their ilk...

https://liam-on-linux.dreamwidth.org/97793.html

(Fairly rare tech blog post, from me. Repurposed Lobsters/HN comment, as often the case.)

Passing thoughts on Universal Blue and their ilk...

It is very odd to me to watch OStree-based distros starting to take off and win recruits.<p>The only reason Red Hat needed to invent this very complex mechanism was because RH does not officially have a COW-snapshot capable filesystem in its enterprise distro.</p> <p>A filesystem with snapshot

Dreamwidth Studios

Future Sprog Mar 4

I never really looked under the hood to figure out how they were doing snapshots. Seems that ostree would be inferior to proper filesystem level snapshots.

@lproven Ostree is not just a virtual FS with snapshotting capabilities. Ostree is image based and kind of declarative. This is not the case for SUSE's snapshotting concept, as far as I'm aware. This allows Ostree to do things that you can't do merely by rolling back snapshots:

@lproven Let's say the OS starts in a state called A1. We now install a package and end up in a new state A1'. Then we update the OS and end up in A2'. Because with Ostree installing packages works by layering, we can now remove that layer again and thus move directly from A2' to A2.

@lproven With SUSE's snapshots we either need to go from A2' back to A1 (if we haven't deleted it already) and then update to A2, or we uninstall the package using the package manager. But depending on the package manager installing and then uninstalling a package might not be guaranteed to lead to the same result as doing nothing. So by uninstalling the package we might actually create a new state A2'' != A2.

@lproven Furthermore with Ostree you can arbitrarely move between different images by using the rebase operation. As far as I'm aware you can even rebase from Silverblue to whatever ublue image and the other way around. Not sure if you can even move between atomic desktops and CoreOS though.

@lproven bootc takes this even a step further by using the standardized OCI image format for it's images.

Graham Perrin Mar 5

@lproven off at a tangent, you might remember … was it Apple, decades ago, that toyed with the idea of a database underlying the file system?

I began using Macs in 1993, so the concept might have been written about some time between 1995 and 1999.

Liam Proven Mar 5

@grahamperrin Not on Macs or MacOS, no. That's something Microsoft tried and failed to make happen in the early days of Windows NT.

Aslak Raanes Mar 5

@lproven @grahamperrin Not what you where thinking of, but the Apple Newton had a database like file system https://en.wikipedia.org/wiki/Soup_(Apple)?wprov=sfti1

Soup (Apple) - Wikipedia

Liam Proven Mar 5

@aslakr @grahamperrin Yes it did. I own 2 of them.

A few years ago I did a main programme talk at the FOSDEM conference in Brussels about an OS designed around Intel Optane style persistent memory, which could entirely remove any need for files or filesystems. The Newton was one of my models and examples.

You might find it interesting.

https://archive.fosdem.org/2021/schedule/event/new_type_of_computer/

FOSDEM 2021 - Starting Over

Kirtai 🏳️‍⚧️Mar 5

@lproven @aslakr @grahamperrin
Ooh, that sounds very very cool.

Liam Proven Mar 5

@kirtai @aslakr @grahamperrin

If, like me, you are more of a reader than a watcher, I also chopped it down to make an article for @theregister ...

https://www.theregister.com/2024/02/26/starting_over_rebooting_the_os/

Starting over: Rebooting the OS stack for fun and profit

Making full effective use of new persistent memory means tearing up the rulebook

The Register

Kirtai 🏳️‍⚧️Mar 5

@lproven @aslakr @grahamperrin @theregister
Thank you, I am very much more of a reader than a watcher

Kirtai 🏳️‍⚧️Mar 5

@lproven @aslakr @grahamperrin @theregister
As a fan of things like Smalltalk, Oberon and persistent operating systems like KeyKOS I really liked this article

Btw, did you know that Smalltalk-76 had an object based virtual memory system called OOZE that transparently let you use the whole of memory and disk as one persistent thing?

Liam Proven Mar 5

@kirtai @aslakr @grahamperrin @theregister

I didn't, no. It's hard to find much good info about Smalltalk and its evolution that is accessible to non-programmers.

Kirtai 🏳️‍⚧️Mar 5

@lproven @aslakr @grahamperrin @theregister
This article by Dan Ingalls covers a lot of it, including OOZE.

Liam Proven Mar 5

@kirtai @aslakr @grahamperrin @theregister Thanks!

Kirtai 🏳️‍⚧️Mar 5

@lproven @aslakr @grahamperrin @theregister
I actually need to reread this myself.

It explains some of the problems I've been having with some recovered files (they're in St74, not St76 as I had assumed)