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Comment by pjmlp | Hacker News Reader

Demo of Mesa/Cedar system, the lesser known system from Xerox ones, written in memory safe systems programming language of the same name, with reference counting and a cycle collector, and those unsafe code blocks.

https://youtu.be/z_dt7NG38V4

Replicates the Lisp and Smalltalk development experience, introduces ideas that were inspiration for Oberon Gadgets, OLE and OpenDoc, had networking, file servers, only downside was being single user workstation.

We as industry are still catching up with that experience and overall system safety.

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Yes, Cedar was impressive, like the adult version of the Oberon system. I wonder if the source code of the Cedar environment is available somewhere. There is an interesting report by Atkinson (and Jacobi, who is on the panel in the posted video) where they migrated the environment to Unix using C as an intermediate layer. This is apparently the version used for the demonstration. But I couldn't yet find this source code anywhere. Maybe someone has a link.

Some of the Xerox PARC digital archives have printouts from Cedar, including the bytecode and microcoded CPU instructions, now if everything is there, no idea.

That version of the Cedar source was on a CD-ROM accompanying the blue-and-white version of this SOSP'93 paper:

Carl Hauser, Christian Jacobi, Marvin Theimer, Brent Welch, and Mark Weiser. 1993. Using threads in interactive systems: a case study. SIGOPS Oper. Syst. Rev. 27, 5 (Dec. 1993), 94–105. https://doi.org/10.1145/173668.168627

Thanks for the hint. It seems the additional data is not available from the ACM site. Was really the source code of the whole environment including the Mimosa compiler on the CD? Do you know anyone who has access to it? I might be interested (if feasible) to migrate and run it on contemporary operating systems.

I really wonder if we're not ready for a compression phase. Simpler, safer, expressive sets of ideas to unify OS/stack/network/UI.

In a sense that is what unikernels/managed runtimes running on top of type 1 hypervisors represent, now if we ever get a consumer OS with that approach, it remains to be seen.

I don't expect to still see it during my lifetime.

Maybe when computing gets rebooted with quantum computing, if you check the languages being used for research (Q#, Qiskit, visual), none of them are classical C or C++ like.

That's on the bare metal side, without disagreeing I was mostly thinking about the ~user/programmer side notion of computing. Tiny blocks of near stateless logical operations streamed (so sync or async or threaded .. no difference). But in a way unikernels are also a way to rethink what a system is.

Take a look at MirageOS (ocaml)

I'd like to think these ideas have been around and well-known for decades, and we're starting to see the hardware rise up to support them. If you told someone in 2001 that Linux would be rewritten in say, Java, with a garbage collector it would have been dismissed as starkly inefficient. Nowadays we have hardware that makes certain safeties negligible on performance (memory tagging, bounds checking, etc). Nowadays we can make an OS out of Java and it will stand just fine. Or Rust. Faster hardware means we run slower (and safer) software. Not everything gets isolated into an ASIC, of course.

They could have made an OS in a managed language decades ago.

They did. They were called LISP machines.

It would still be dismissed as starkly inefficient, because the problem isn't technology, rather mentalities.

Midori powered Asian Bing as proof of its capabilities, and yet Windows team was dismissal of its capabilities and instead went on reinventing .NET with COM, aka .NET Native and C++/CX alongside WinRT. A kind of ironic given that it was .NET original design (codename Ext-VOS), before they decided to reboot COM with a managed runtime, alongside the J++ issues that caused COOL to become C# instead.

Quite interesting feedback from Joe Duffy how everything went down,

"Safe Systems Programming in C# and .NET" - https://www.infoq.com/presentations/csharp-systems-programmi...

"RustConf 2017 - Closing Keynote: Safe Systems Software and the Future of Computing" - https://www.youtube.com/watch?v=EVm938gMWl0

> OS and tools for building dependable systems. The Singularity research codebase and design evolved to become the Midori advanced-development OS project. While never reaching commercial release, at one time Midori powered all of Microsoft’s natural language search service for the West Coast and Asia.

https://www.microsoft.com/en-us/research/project/singularity...

Ironically, despite still having the Linux kernel underneath and enough C++, Android and ChromeOS are probably the mainstream OSes that are closer to the overall idea, at least in what concerns userspace applications.

As on the Microsoft side, WinDev seems to always sabotage those ideas, as you can infer from Joe Duffy talks, and from Apple side although Swift is supposed to play a major role going forward, C, C++ and Objective-C still represent the majority of the stack.

>> The Singularity research codebase and design evolved to become the Midori advanced-development OS project. While never reaching commercial release, at one time Midori powered all of Microsoft’s natural language search service for the West Coast and Asia.

> https://www.microsoft.com/en-us/research/project/singularity...

> Ironically, despite still having the Linux kernel underneath and enough C++, Android and ChromeOS are probably the mainstream OSes that are closer to the overall idea, at least in what concerns userspace applications.

Singularity uses a proprietary language-based microkernel. Midori was allegedly an attempt at a commercial version of Singularity, and I'm not sure what is different about the two, but Midori also uses a microkernel. Linux famously uses a monolithic kernel. Also, consider, any operating system that uses the Linux kernel... is Linux by definition, though technically Linux is the kernel, GNU/Linux is the OS.

There is a piece of container management software, I think that's what it is, called Singularity, and it uses the Linux kernel running on Linux. Maybe you were thinking of the wrong Singularity.

Yes Singularity uses a C++ based microkernel and everything else is written in Sing#, what is your point?

Midori has nothing to do with Singularity in architecture other than being a second attempt from the same group of researchers at a memory safe OS.

Android and Chrome OS aren't Linux, they use a highly customized Linux kernel, in fact after Project Treble it is so customized that it could almost be considered a pseudo-microkernel, as all Treble drivers exist as user processes, use Android IPC to talk to the kernel and since Android 8 all drivers must be Treble based (Android considers the Linux kernel drivers as "legacy drivers").

Finally I don't see how Singularity and the Linux kernel have anything to do with each other, my examples with Android and ChromeOS are what I mentioned in relation with the Linux kernel.

> Ironically, despite still having the Linux kernel underneath

I misread what you were referring to is all. I thought you were saying Singularity ran on the kernel linux, but you were not saying that at all. You were talking about the GNUless Android and ChromeOS. Comprehension is underrated.

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