10 ms·

Plan9-9k: 64-bit Plan 9

197 points by gkya 9y ago

f2f 9y 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/ 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! ;)
- butterisgood 9y 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 http://vitanuova.com/inferno/index.html It can run without an MMU too. It's been ported to the Nintendo DS.
tombert 9y 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.
- butterisgood 9y 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 9y 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?
    - butterisgood 9y ago
      Well the nice thing, maybe, about Plan 9's virtualization of resources is that they all follow some 9P variant (simple protocol). 9p is v9fs in linux. There's FUSE 9p stuff for other platforms. There's a virtualized Erlang runtime that sits directly on Xen as the OS that uses 9p. 9p is part of QEMU's way of talking to the guest (or is it the host?) OS. It's been on a lego mindstorm brick too. To me, kernel dbus is a bit more like mach_ports. Those have their own advantages too. As did Solaris Doors.
    - shimon_e 9y ago
      Linux is no longer pure Unix. Linux has adopted parts of plan 9.
    - ori_b 9y ago
      > If we extend dbus to be similarly pervasive in Linux That kind of pervasiveness involve replacing all i/o through the entire system with dbus. File systems, netlink, sun rpc, mmap, signals and kill, tcp, and so on. And then making dbus sanely deal with networking and authentication. 9p isn't just pervasive: it's the only way to talk to the system, which means that if you want to mess with namespacing things, all you need to think about is 9p.
- qubex 9y 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 9y 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.
- f2f 9y 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 http://catb.org/~esr/writings/taoup/html/plan9.html
- m_sahaf 9y 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
  - pjmlp 9y 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.
    - butterisgood 9y ago
      John Carmack used to participate in the Plan 9 mailing lists https://marc.info/?a=111558719100068&r=1&w=4 https://marc.info/?a=111558719100068&r=1&w=4 Though Rob Pike might have not been very cooperative or enthusiastic https://marc.info/?l=9fans&m=111558699517143&w=4 https://marc.info/?l=9fans&m=111558699517143&w=4 He goes on about some interesting architectural advantages already in Plan 9 from a graphics programming standpoint and capitalizing on them someday. It'd be interesting to hear about how far along he got. https://marc.info/?l=9fans&m=111558698816997&w=4 https://marc.info/?l=9fans&m=111558698816997&w=4 Here he talks about trying to hack Plan 9 to run Quake https://marc.info/?l=9fans&m=111558698416915&w=4 https://marc.info/?l=9fans&m=111558698416915&w=4
      - pjmlp 9y ago
        Interesting read, including some QNX and Amiga related stuff, thanks.
  - naasking 9y 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 9y 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 https://en.wikipedia.org/wiki/Plan_9_from_Bell_Labs
- fusiongyro 9y 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.
  - gigatexal 9y 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?
    - qubex 9y ago
      This isn't really a ’project’ in the sense you seem to intend: it was a 1990s AT&T research project that was abandoned and released under an open source licence in the mid-2000s.
      - gigatexal 9y ago
        Bum deal. There seems to be some interest at least here on HN, perhaps someone or a group of someones could pick it up and bring it to bear for 2017+?
- dflock 9y 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. More: http://en.wikipedia.org/wiki/Plan_9_from_Bell_Labs http://en.wikipedia.org/wiki/Plan_9_from_Bell_Labs http://plan9.bell-labs.com/plan9/ http://plan9.bell-labs.com/plan9/ http://en.wikipedia.org/wiki/9P2000 http://en.wikipedia.org/wiki/9P2000 http://en.wikipedia.org/wiki/V9fs http://en.wikipedia.org/wiki/V9fs http://en.wikipedia.org/wiki/List_of_distributed_computing_projects http://en.wikipedia.org/wiki/List_of_distributed_computing_p... http://en.wikipedia.org/wiki/Inferno_$operating_system$ http://en.wikipedia.org/wiki/Inferno_$operating_system$ http://doc.cat-v.org/plan_9/4th_edition/papers/plumb http://doc.cat-v.org/plan_9/4th_edition/papers/plumb http://swtch.com/plan9port/ http://swtch.com/plan9port/
  - pmoriarty 9y 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/ https://lwn.net/Articles/325369/ [2] - https://www.mjmwired.net/kernel/Documentation/filesystems/9p.txt https://www.mjmwired.net/kernel/Documentation/filesystems/9p...
- pjmlp 9y 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/ 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/ http://www.vitanuova.com/inferno/
  - butterisgood 9y ago
    Go and Limbo have newsqueak as an ancestor. https://en.wikipedia.org/wiki/Newsqueak 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) https://en.wikipedia.org/wiki/Alef_(programming_language)
- bitwize 9y 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.
qubex 9y 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...)
- butterisgood 9y ago
  There's Plan 9 Front. http://9front.org 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.
  - qubex 9y 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.
    - butterisgood 9y ago
      Ok, well I lived in google chrome mosh for about 4 months. It was fine :-) Full screen too.
    - derefr 9y ago
      > bastardising everything so Linux binaries run on it kind of defeats the point Is there all that much of a difference between the kind of "secondary syscall ABI" approaches that allow OSes like Windows and Illumos to virtualize Linux binaries, and autoconf-based porting of those projects so they compile for the target OS, if they only use POSIX facilities that both OSes offer the same way anyway? I mean, I agree with you when it comes to e.g. programs that use heavy amounts of OS-specific concurrency or IPC primitives. Postgres in WSL on Windows does not have the same concurrency semantics as MSSQL on Windows does, because Postgres is using POSIX concurrency primitives and MSSQL is using NT concurrency primitives. But if there's a subset of your kernel's syscall ABI, that already has those same semantics, and really can just be 1:1 mapped with maybe a few extra instructions to handle different argument passing conventions—then does porting such a program to the OS really achieve anything?
kruhft 9y 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.
- xfer 9y 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.
  - kruhft 9y ago
    How would you remove it from the kernel?
    - xfer 9y ago
      you don't need to remove it from kernel. You can choose which service to run on a machine. A 'terminal' can be configured without running auth service. But you need an auth server when you communicate with other machines.
      - kruhft 9y ago
        I want all auth removed.
        deleted 9y ago
        [deleted]
- bakul 9y 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.
pjmlp 9y 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 9y ago
  There is an inferno with lua project, on this theme; see https://news.ycombinator.com/item?id=9704517 https://news.ycombinator.com/item?id=9704517
- octetta 9y 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?
  - ptomato 9y 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
    - hawski 9y ago
      Better just call it Dante or Dante's.
      - dangerbird2 9y ago
        It's clever, but "Dante's Inferno" is one of the few names more difficult to google than "go"
        jhoechtl 9y ago
        You would google for golang
  - 9y ago
bloaf 9y 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 9y ago
  Could you expand on that point? While I'm not knowledgeable on the topic I'm genuinely curious to hear a few examples.
  - bloaf 9y ago
    I think this says it very well: http://www.catb.org/esr/writings/taoup/html/plan9.html 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 9y 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 9y 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.

197 points by gkya 9y ago

f2f 9y 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/ 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! ;)

butterisgood 9y 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 http://vitanuova.com/inferno/index.html It can run without an MMU too. It's been ported to the Nintendo DS.

tombert 9y 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.

butterisgood 9y 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 9y 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?
  - butterisgood 9y ago
    Well the nice thing, maybe, about Plan 9's virtualization of resources is that they all follow some 9P variant (simple protocol). 9p is v9fs in linux. There's FUSE 9p stuff for other platforms. There's a virtualized Erlang runtime that sits directly on Xen as the OS that uses 9p. 9p is part of QEMU's way of talking to the guest (or is it the host?) OS. It's been on a lego mindstorm brick too. To me, kernel dbus is a bit more like mach_ports. Those have their own advantages too. As did Solaris Doors.
  - shimon_e 9y ago
    Linux is no longer pure Unix. Linux has adopted parts of plan 9.
  - ori_b 9y ago
    > If we extend dbus to be similarly pervasive in Linux That kind of pervasiveness involve replacing all i/o through the entire system with dbus. File systems, netlink, sun rpc, mmap, signals and kill, tcp, and so on. And then making dbus sanely deal with networking and authentication. 9p isn't just pervasive: it's the only way to talk to the system, which means that if you want to mess with namespacing things, all you need to think about is 9p.
qubex 9y 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 9y 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.
f2f 9y 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 http://catb.org/~esr/writings/taoup/html/plan9.html
m_sahaf 9y 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
- pjmlp 9y 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.
  - butterisgood 9y ago
    John Carmack used to participate in the Plan 9 mailing lists https://marc.info/?a=111558719100068&r=1&w=4 https://marc.info/?a=111558719100068&r=1&w=4 Though Rob Pike might have not been very cooperative or enthusiastic https://marc.info/?l=9fans&m=111558699517143&w=4 https://marc.info/?l=9fans&m=111558699517143&w=4 He goes on about some interesting architectural advantages already in Plan 9 from a graphics programming standpoint and capitalizing on them someday. It'd be interesting to hear about how far along he got. https://marc.info/?l=9fans&m=111558698816997&w=4 https://marc.info/?l=9fans&m=111558698816997&w=4 Here he talks about trying to hack Plan 9 to run Quake https://marc.info/?l=9fans&m=111558698416915&w=4 https://marc.info/?l=9fans&m=111558698416915&w=4
    - pjmlp 9y ago
      Interesting read, including some QNX and Amiga related stuff, thanks.
- naasking 9y 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 9y 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 https://en.wikipedia.org/wiki/Plan_9_from_Bell_Labs
fusiongyro 9y 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.
- gigatexal 9y 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?
  - qubex 9y ago
    This isn't really a ’project’ in the sense you seem to intend: it was a 1990s AT&T research project that was abandoned and released under an open source licence in the mid-2000s.
    - gigatexal 9y ago
      Bum deal. There seems to be some interest at least here on HN, perhaps someone or a group of someones could pick it up and bring it to bear for 2017+?
dflock 9y 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. More: http://en.wikipedia.org/wiki/Plan_9_from_Bell_Labs http://en.wikipedia.org/wiki/Plan_9_from_Bell_Labs http://plan9.bell-labs.com/plan9/ http://plan9.bell-labs.com/plan9/ http://en.wikipedia.org/wiki/9P2000 http://en.wikipedia.org/wiki/9P2000 http://en.wikipedia.org/wiki/V9fs http://en.wikipedia.org/wiki/V9fs http://en.wikipedia.org/wiki/List_of_distributed_computing_projects http://en.wikipedia.org/wiki/List_of_distributed_computing_p... http://en.wikipedia.org/wiki/Inferno_$operating_system$ http://en.wikipedia.org/wiki/Inferno_$operating_system$ http://doc.cat-v.org/plan_9/4th_edition/papers/plumb http://doc.cat-v.org/plan_9/4th_edition/papers/plumb http://swtch.com/plan9port/ http://swtch.com/plan9port/
- pmoriarty 9y 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/ https://lwn.net/Articles/325369/ [2] - https://www.mjmwired.net/kernel/Documentation/filesystems/9p.txt https://www.mjmwired.net/kernel/Documentation/filesystems/9p...
pjmlp 9y 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/ 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/ http://www.vitanuova.com/inferno/
- butterisgood 9y ago
  Go and Limbo have newsqueak as an ancestor. https://en.wikipedia.org/wiki/Newsqueak 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) https://en.wikipedia.org/wiki/Alef_(programming_language)
bitwize 9y 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.

qubex 9y 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...)

butterisgood 9y ago
There's Plan 9 Front. http://9front.org 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.
- qubex 9y 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.
  - butterisgood 9y ago
    Ok, well I lived in google chrome mosh for about 4 months. It was fine :-) Full screen too.
  - derefr 9y ago
    > bastardising everything so Linux binaries run on it kind of defeats the point Is there all that much of a difference between the kind of "secondary syscall ABI" approaches that allow OSes like Windows and Illumos to virtualize Linux binaries, and autoconf-based porting of those projects so they compile for the target OS, if they only use POSIX facilities that both OSes offer the same way anyway? I mean, I agree with you when it comes to e.g. programs that use heavy amounts of OS-specific concurrency or IPC primitives. Postgres in WSL on Windows does not have the same concurrency semantics as MSSQL on Windows does, because Postgres is using POSIX concurrency primitives and MSSQL is using NT concurrency primitives. But if there's a subset of your kernel's syscall ABI, that already has those same semantics, and really can just be 1:1 mapped with maybe a few extra instructions to handle different argument passing conventions—then does porting such a program to the OS really achieve anything?

kruhft 9y 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.

xfer 9y 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.
- kruhft 9y ago
  How would you remove it from the kernel?
  - xfer 9y ago
    you don't need to remove it from kernel. You can choose which service to run on a machine. A 'terminal' can be configured without running auth service. But you need an auth server when you communicate with other machines.
    - kruhft 9y ago
      I want all auth removed.
      - deleted 9y ago
        [deleted]
bakul 9y 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.

pjmlp 9y 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 9y ago
There is an inferno with lua project, on this theme; see https://news.ycombinator.com/item?id=9704517 https://news.ycombinator.com/item?id=9704517
octetta 9y 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?
- ptomato 9y 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
  - hawski 9y ago
    Better just call it Dante or Dante's.
    - dangerbird2 9y ago
      It's clever, but "Dante's Inferno" is one of the few names more difficult to google than "go"
      - jhoechtl 9y ago
        You would google for golang
- 9y ago

bloaf 9y 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 9y ago
Could you expand on that point? While I'm not knowledgeable on the topic I'm genuinely curious to hear a few examples.
- bloaf 9y ago
  I think this says it very well: http://www.catb.org/esr/writings/taoup/html/plan9.html 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 9y 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 9y 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.