Plan9-9k: 64-bit Plan 9

https://bitbucket.org/forsyth/plan9-9k

by _pfxa • 9 years ago

197 97 9 years ago

bitbucket.org

f2f2• 9 years ago

A little bit of history: Forsyth did the 64-bit compiler for the Plan 9 on Blue Gene project.

http://doc.cat-v.org/plan_9/blue_gene/

(I contributed to the project too: I did the photochop of glenda on the side of the BG racks! ;)

butterisgood7• 9 years ago

Forsyth is also "the Inferno guy" (well, one of them!). I've had a lot of fun playing around with that little OS over the years.

http://vitanuova.com/inferno/index.html

It can run without an MMU too. It's been ported to the Nintendo DS.

tombert• 9 years ago

I've read a lot of places that say "Plan 9 is basically a better Unix", but I'm not entirely sure why. Can someone explain what made Plan-9 special? I'm not asking in a passive aggressive sense, I genuinely want to know.

butterisgood7• 9 years ago

Everything is a file system. You can mount almost all things. All things have private namespaces by default.

Right down to the TCP/IP stack... you can run a program called "sshnet" and connect to a remote unix box, the /net in that process' namespace now has a tunnel to the remote box, and all children of that process that opt-in to share the namespace now have a VPN-like to the network you just ssh'd to.

Because the network stack is a file system you can do basic open, read, write, close stuff to dial up remote services and work with them. As such there's IRC clients written in the shell, without evil extensions like /dev/tcp in bash.

It's fun, but it doesn't outrun any other OS I've seen. Maybe that's changed.

Asooka• 9 years ago

Honest question: If we extend dbus to be similarly pervasive in Linux (via BUS1 or whatever ends up being merged), won't it have pretty much the same benefits? Once it's in-kernel I'm 100% sure we'll end up with a virtual file system for accessing it. It will definitely never be quite as elegant and integrated in the system as Plan9, but maybe we could reap similar benefits?

qubex4• 9 years ago

In Plan9 UNIX's ”everything is a file” philosophy is reaffirmed in a heightened and enhanced form, and all resources (CPUs, even) on a distributed network can be mounted with a simple protocol and accessed remotely. These namespaces make it possible to provide each and every program with its own namespace (to the point of being able to run a copy of the window manager within itself). For example you have /net directories with all the TCP ports in /net/tcp and those can be concatenated to forward ports or even create routers. It's amazing.

jacquesm• 9 years ago

In a nutshell, and somewhat simplified: it cleans up the /dev/ interface and turns everything into streams of characters and mounts. So rather than a bunch of messy ioctls and other out-of-band mechanisms it just works with streams. This is nice because it allows you to use remote resources as if they're local.

Distributed name spaces, distributed computing, compute servers, distributed file servers and so on.

Remember the SUN slogan 'the network is the computer'? Plan 9 makes that a reality.

f2f2• 9 years ago

I think ESR summarized it very well for the layman almost 20 years ago in "the art of unix programming":

http://catb.org/~esr/writings/taoup/html/plan9.html

m_sahaf• 9 years ago

I've played with Pla9 a bit and I find it overall interesting. Here are the things from the top of my head that are improvements over Unix:

- Truly everything is a file. No exceptions; no special cases.

- Symlinks do not feel like a hack causing trouble. If you need a reference to a directory in another path, you mount it. If your software writes its binaries into its custom directory and you want the binaries within the $PATH, you mount that custom directory into /bin (or so, from what I remember).

- Namespace isolation for processes.

- Distributed file system

pjmlp12• 9 years ago

Truly everything is a file. No exceptions; no special cases.

As graphics fan, I wonder how this would work out with modern GPU driver layers.

naasking2• 9 years ago

- Namespace isolation for processes.

This is seriously underappreciated IMO. You can entirely replace access control with private namespaces without any real loss in generality. In fact, they're more flexible and secure.

pfranz• 9 years ago

It's probably more accurate to say it was intended to be the successor of UNIX. Plan 9 was developed by the same group that developed UNIX (Bell Labs) with many of the same prominent people credited with C and UNIX; Rob Pike, Ken Thompson, Dennis Ritchie.

https://en.wikipedia.org/wiki/Plan_9_from_Bell_Labs

fusiongyro3• 9 years ago

Plan 9 shows that you can reduce the complexity of Unix by changing the idea behind mount slightly (mounts are inherited by processes rather than global) and creating a simple network filesystem protocol that applications can use to expose their state through.

In Unix you often get stuck having to create these walled-off systems. Your editor's inner state, for instance, is not visible to other applications, so you need to come up with your own whole programming scheme. Same with your window manager. And all your networking happens through a separate set of APIs that are similar to the file descriptor APIs but different enough that nothing works transparently.

Once you have per-process mounts and a simple network filesystem, all your applications and devices can start exposing their state over that protocol. All your software and hardware are automatically networkable if you follow the design. And you can use Unix utilities to do things that previously would require whole subsystems to be built. You don't need to build your own programming language for Acme, because Acme's state is visible as a filesystem. Same with the window manager. And you don't need to build a custom networking scheme for sharing Acme with your friend on another machine, because you can export Acme's filesystem to that machine (or have your friend export their keyboard onto your machine as a child of the Acme process).

"Everything really is a file" is a good way to sum it up. But that's only possible and relatively safe because of 9P and per-process namespaces.

gigatexal4• 9 years ago

that sounds really simple and powerful. i am keen to start following this project. Is there a patreon or a donation portal to help fund development?

ianai2• 9 years ago

Wait, are people actually taking plan9 seriously now?

ninkendo• 9 years ago

Your editor's inner state, for instance, is not visible to other applications, so you need to come up with your own whole programming scheme.
Same with your window manager.
You don't need to build your own programming language for Acme, because Acme's state is visible as a filesystem.

I don't see how it's good programming practice to expose your internal state to direct read/write access from other programs. It seems to violate basic encapsulation principles.

Your quotes are making me think of some really important takeaways from the Longhorn disaster with WinFS, detailed in a recent submission[1]:

More profoundly, Bill’s vision of an ecosystem of applications that all store and share their data in this relational store is in direct conflict with how applications build their data models. While some desktop applications (and almost all internal IT-written ones) use relational stores for their internal data model, they do not want to expose those data models for unmonitored read and write by other applications. I detailed some of the fundamental reasons in the post referenced above, Leaky by Design.[2]

Solutions like this... "what if application state were like a relational data store, or hierarchical FS, that other programs can access", sounds great as a fun programming exercise, but it isn't often how people actually want to design applications.

[1] https://hackernoon.com/what-really-happened-with-vista-4ca7f... [2] https://hackernoon.com/leaky-by-design-7b423142ece0

dflock2• 9 years ago

It's a truly distributed operating system and it's unix taken to it's logical conclusion. Everything is a file and everything is network transparent, thanks to 9P. The first wikipedia article is very worthwhile reading - this is a little except that gives you the idea:

"Unix allows file systems to be built up from disparate resources using concepts such as links and file system mounts. These features masked the original directory; if one mounts a new filesystem on the directory named "net", one can no longer access its previous contents until the operation is reversed.
Plan 9 introduced the idea of union directories, directories that combine resources across different media or across a network, binding transparently to other directories. For example, another computer's /bin (applications) directory can be bound to one's own, and then this directory will hold both local and remote applications and the user can access both transparently.
Using the same system, under Plan 9 external devices and resources can be bound to /dev, allowing any device to be shared over the network without any additional code."

So, you can union mount other machines /dev/cpu/ folders into your machine's /dev/cpu folder and then have access to all the CPU's. Same for all other hardware, software and storage.

Just these two things - Union Mounts and 9P - when built into the whole system, create a very dynamic distributed computing environment. I really, really wish more of this would make it into Linux. We've kinda got some of it, but without joining up all the other bits, the real power isn't quite there.

http://en.wikipedia.org/wiki/Plan_9_from_Bell_Labs http://plan9.bell-labs.com/plan9/ http://en.wikipedia.org/wiki/9P2000 http://en.wikipedia.org/wiki/V9fs http://en.wikipedia.org/wiki/List_of_distributed_computing_p... http://en.wikipedia.org/wiki/Inferno_$operating_system$ http://doc.cat-v.org/plan_9/4th_edition/papers/plumb http://swtch.com/plan9port/

pmoriarty4• 9 years ago

"Just these two things - Union Mounts and 9P - when built into the whole system, create a very dynamic distributed computing environment. I really, really wish more of this would make it into Linux."

Union mounts and 9P are already available in Linux.[1][2] What other things would you like to see?

[1] https://lwn.net/Articles/325369/

[2] https://www.mjmwired.net/kernel/Documentation/filesystems/9p...

pjmlp12• 9 years ago

Somehow many Plan 9 fans seem to forget that the design continued as Inferno.

So with that in mind, I would rephrase that as "Inferno is basically a better Unix".

You can learn more about it, including the programming manual with lots of Limbo examples at:

http://doc.cat-v.org/inferno/4th_edition/

You can easily see some of Go's pedigree on Limbo's design.

Nowadays Inferno is still being sold by Vita Nuova, the company that acquired the rights after Bell Labs folded the project.

http://www.vitanuova.com/inferno/

butterisgood7• 9 years ago

Go and Limbo have newsqueak as an ancestor.

https://en.wikipedia.org/wiki/Newsqueak

Alef was pretty neat too and was also on Plan 9

https://en.wikipedia.org/wiki/Alef_(programming_language)

bitwize• 9 years ago

In Plan 9, everything literally is a file. Processes communicate using the 9p protocol which is also the basis of the file system; each process also has its own, local view of the file tree which children can inherit (or not). To do IPC with a server process, simply mount it and begin reading and writing to files in the mounted directory. Oh, and 9p is network-transparent, so you can see remote files and processes as if they were local.

It really is a neat idea, and shows what can be done when you take an idea to its logical extreme. But the interface is not human friendly. Real-world workloads are complicated and require kernels that handle the weird edge cases so you can't reduce a production kernel to a simple idea. And 9p performance lags behind other networked file systems. So it's really more of a prototype and a laboratory for generating ideas to be used in other systems, rather than a replacement for production Unix.

qubex4• 9 years ago

I've always had a soft spot for Plan9 (on account of its architectural purity) but I've never managed to make it a ”daily driver” despite sincerest efforts (this coming from somebody who fondly remembers using BeOS pretty exclusively for at least a couple of years in the latter half of the nineties).

Maybe this will reignite interest in the platform? Maybe somebody will go ahead to port it to 64 bit ARM so it can be tried on the latest Raspberry Pi? (Yes I know the 32 bit version exists and works, but...)

butterisgood7• 9 years ago

There's Plan 9 Front.

http://9front.org

I've used Plan 9 a few times in the last handful of years.

Someone got a reasonably good Linux emulator working enough to run Firefox. What more could you need? (ok it was fairly limited in some ways, but shoot once you have a web browser, most of the rest is cake... especially if it's Chrome, because then you can install Mosh inside it!)

Not sure if that's practical on Plan 9 right now.

qubex4• 9 years ago

Call me odd, but I like native software — web-apps et al are not my style. Similarly, bastardising everything so Linux binaries run on it kind of defeats the point (at least in my mind). But yeah, I'm odd.

rcarmo3• 9 years ago

It wasn't a year back, at least for relatively recent versions. Nothing substantial has changed, so I think it still isn't

pmoriarty4• 9 years ago

"Someone got a reasonably good Linux emulator working enough to run Firefox. What more could you need?"

It would be nice if Plan 9 had vim or emacs.

ZephyrP2• 9 years ago

A common thing to do here is to virtualize 9front, connect back to a VNC window hosting Chrome. It sounds really janky but it's genuinely difficult to tell that you're not inside Chrome -- people have even asked "How in did you port Chrome to Plan 9.

still_grokking• 9 years ago

I didn't know Mosh until now. Thank you so much for mentioning it! :-)

kruhft7• 9 years ago

I'd love to be able to sit down and learn Plan9. The shell is awesome (rc), the commands are somewhat familiar, but the networking is totally foreign and security setup (factotum I think) I obtuse. I want a Plan9 kernel with no security for playing and architecting with...they took a great idea and ruined with security. That should be the outer layer of the system.

xfer2• 9 years ago

factotum is similar to kerberos iirc. Plan9 was deisgned as distributed computing environment(separating fs, cpu and auth). Although you can and many people do run all of them on same machine.

kruhft7• 9 years ago

How would you remove it from the kernel?

bakul• 9 years ago

Richard Miller's port of plan9 runs on every RaspberryPi (pi0 to pi3 - where it uses all the cores). This may be the easiest way to experience plan9 and to build a small distributed system. You can experiment with device drivers or do other kernel hacking fairly quickly -- compiling p9 kernel from scratch takes about a minute on a 'Pi. This is good enough if you just want to play with plan9. You need not bother with an x86 system unless you want to use plan9 as your main system or for some serious work.

kruhft7• 9 years ago

Linkage: http://raspi.tv/tag/richard-miller-plan-9

pa7ch3• 9 years ago

The dream of the plan9 filesystem may be alive in upspin (https://upspin.io/). Its a federated filesystem/protocol with a global namespace. The security story could arguably be described as a layer on top of any application built with it in mind.

I've just begun experimenting with it on my personal server and like it so far. Its still an early project though.

kruhft7• 9 years ago

Does it support remote devices like 9p?

pjmlp12• 9 years ago

Actually I would rather see someone pick up Inferno and replace Limbo with Go.

Personally I see Plan9 just as a plain transition step between UNIX and Inferno, where the goodies in terms of architecture actually are.

Palomides• 9 years ago

There is an inferno with lua project, on this theme; see https://news.ycombinator.com/item?id=9704517

octetta2• 9 years ago

I agree 100%. I do wonder if the Dis VM is a close enough match for Go as a target. Or perhaps we could start with a simple Go to Limbo translation transpiler. Want to see if it's possible?

vluft• 9 years ago

I do wonder if the Dis VM is a close enough match for Go as a target

obviously you would call this DisGo and the resulting system would be DisGo Inferno

rurban• 9 years ago

But this would need a Go with generics and polymorphism then. PolyGo or such. For simple server stuff Go is enough but for a dynamic VM with dynamic objects not.

Crontab• 9 years ago

I think you are the first person I've seen speak highly of Inferno. I've played with Plan 9 from time to time, so if you have a moment, can you tell me what you like about it?

pjmlp12• 9 years ago

Sure, are you aware of Inferno's web site?

http://doc.cat-v.org/inferno/4th_edition/

It contains quite some useful information, including the book "Inferno Programming with Limbo" http://doc.cat-v.org/inferno/books/inferno_programming_with_...

Being a security oriented developer, I like that they decided to use a managed language for the whole userspace (Limbo) leaving C for the kernel and compatibility with UNIX software.

Basically, the distributed computing ideas and Oberon influences from Plan 9, merged with type safety.

In a certain way, what Android came to be, almost 20 years before it existed.

kruhft7• 9 years ago

Inferno is cool.

rcarmo3• 9 years ago

That would be nice, but I'd probably prefer to have a UI that I could use without a three-button mouse...

pjmlp12• 9 years ago

Then you can either settle on Windows or OS X, I guess.

My X Windows is a bit rusty, but I remember most managers use all three buttons.

bloaf2• 9 years ago

I hope someone can find a niche for Plan 9, be it on the RPi or somewhere else. So many of its ideas seem to me to be obviously correct in the sense that they logically and conceptually-purely fix the warts other Unix-like OSes have.

cnnrro• 9 years ago

Could you expand on that point? While I'm not knowledgeable on the topic I'm genuinely curious to hear a few examples.

bloaf2• 9 years ago

I think this says it very well:

http://www.catb.org/esr/writings/taoup/html/plan9.html

One of the examples from the Plan 9 survey paper is the way FTP access to remote sites is implemented. There is no ftp(1) command under Plan 9. Instead there is an ftpfs fileserver, and each FTP connection looks like a file system mount. ftpfs automatically translates open, read, and write commands on files and directories under the mount point into FTP protocol transactions. Thus, all ordinary file-handling tools such as ls(1), mv(1) and cp(1) simply work, both underneath the FTP mount point and across the boundaries with the rest of the user's view of the namespace. The only difference the user (or his scripts and programs) will notice is retrieval speed.

someSven• 9 years ago

Short question: What were the downsides to use Plan9 or Inferno as the fundament of a distro insted of Linux? Of course with Linux programms where it would be necessary.

zanny• 9 years ago

It doesn't have glibc or gcc support so the only compiler you have is the non-standard ansc C compiler in Plan 9 (and several efforts to introduce other languages have popped up over time but to my knowledge never took off and required a lot of novel code to make work). This means almost all current software cannot be compiled on Plan9.

So the Linux programs that would be necessary are glibc and gcc, and if you had those you would be able to compile most command line software except for anything that used anything but the standard C library (which would now have been ported to Plan9). Of course, anything accessing most files in a Linux filesystem would break, since Plan9 uses a different layout, and anything that called Linux system calls directly would also break, even UNIX ones, because Plan9 is not Unix.

Going up the stack just makes things worse. You couldn't use any GUI program because you don't have GLX or EGL support for render targets. You don't have OpenGL, so anything written against that can't work.

So you are basically restricted to command line programs that are isolated and make no attempt to use kernel features or arbitrary files in the file system. Even simple things you don't innately think of, like XDG directories, aren't available in a Plan9 environment because its not an X system, so software that uses those won't be able to find the standard config or local cache directories (they will just pull blank envrionment variables and at best write to the current working directory). If you set those variables up manually, you could run stateful software... that didn't use direct Unix system calls.

On the bright side, you could probably get some programming language runtimes to work. Depends on if, say, your Python interpreter uses platform specific system calls or only depends on libc. CPython at least absolutely does have platform specific code paths that would break on Plan9 (because they would assume Unix defaults in the absence of Darwin or NT) but I'm not sure about, say, Pypy. Those runtimes would still be constrained to text only, since the Plan9 graphics layer isn't related to anything in Linux.

Plan9 isn't a kernel, its an operating system in the RMS GNU/Linux sense. Linux distros really depend more in general software on the GNU part than the Linux part, which is both why projects like Debian can drop in Hurd and not have billions of man hours of porting work to do to make it happen and why traditional desktop Linux applications aren't all over Android.

gkya• 9 years ago

Plan 9 is a complete OS, so things like coreutils are not really necessary (tho plan 9 utilities are not strictly POSIX compatible). The killer app would be a good enough web browser, if you're talking about a workstation OS. Other than that it already has a vast set of utilities, including an extensible text editor (acme), mail, etc. for development work .

Plan9-9k: 64-bit Plan 9

Related Stories