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Adopt a Lost Technology Today For R.O.S.
submitted by Simon Strandgaard writes "When new operating systems gets designed today, great systems such as Amiga, Atari and VMS, seems to get overlooked in regard to their original features not found on other OSes. It might be time to collect and categorize those special unique features under the great/lost ideas wiki, so new OSes don't have to re-invent the wheel and re-innovate." This is all for R.O.S., a "ruby-centric operating system."
How many operating systems do we need? Why not find your favorite, and try to impliment these awesome features you like?
Pretty Pictures!
Maybe they should call it the "Ruby-centric Operating Uniformly System"...that way they'd already have a mascot.
Every time a guy gets a threesome, somewhere in heaven an angel gets his wings. --Cary Tennis
..isn't this all pie in the sky stuff though really?
I mean with regards to putting it into action.
-- If I were a fish, I'd be wet
Look at Plan9 for ideas!
In theory it fixes all the problems with Unix, while still keeping to the original design philosophy.
I'd like to see the end of the kernel/userspace separation. Just put everything in one address space. With safe languages, there is no need for it. The safe language you can get fine-grained protection with close to zero performance overhead. This makes the VM a great deal less complex (read Charles Cranor's UVM paper to see the complexity cause by VM-enabled sharing) and faster/less memory-hungry.
Performance should improve a lot too. A P4 pays a couple of hundred clock-cycles penalty for each system call. Context switches are close to 1000 clocks. With a single address-space OS, you can get all the advantages of a microkernel providing services via OS servers, without any performance hit.
A deep unwavering belief is a sure sign you're missing something...
Since VMS was mentioned, I'd like to let people know about this project:
FreeVMS (Mailing list archive)
It's based on Linux for the moment, but it'll split eventually. Despite the homepage being a bit out of date, the project is alive; in fact I'm working on cleaning up the code a bit.
Ron Paul 2012
... for my card reader.
-- Alastair
And you would have to have a "safe"-language-only policy on such a system, or you would have a security nightmare similar to that of MS-Windows.
(I certainly wouldn't want to use such a system; I like C, even though I usually use Python (a "safe" language).)
Performance could be enhanced by doing more things in libraries (e.g., a ramdisk used exclusively by one application (or a limited set of mutually-trusted/ing applications) could be supported entirely in userspace, with no context-switching necessary).
Or several mutually-trusting/ed intercommunicating apps could share the same address space, so no VM remapping would be necessary when switching from one to another, nor would a system call be necessary.
(This would be kind of like a lightweight thread mechanism, but different threads could be loaded from different binaries.)
I don't know if any of this would actually be feasible, though, since I haven't really worked on the guts of an OS for about 20 years.
Those who sacrifice security to condemn liberty deserve to repeat history or something. - Benjamin Santayana
You mean like MS-Windows? :)
:)
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Yeah, but with a safe language
With safe languages, there is no need for it.
The problem with "safe" languages is that the underlying system can be used for such odious purposes as D"R"M, and there is no way to get around it.
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Not at all. Systems-level safe languages (Lisp, for example) usually have a dialect used for kernel-level development. In this scheme, binaries would have to be signed, to ensure that the native code was compiled by the safe compiler. However, this signing only has to be strong enough to protect a traditional security model. Root users, of course, should be allowed to run unsafe, kernel-level code if they want.
And you would have to have a "safe"-language-only policy on such a system, or you would have a security nightmare similar to that of MS-Windows.
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You could always run "unsafe" code in a virtual machine.
(I certainly wouldn't want to use such a system; I like C, even though I usually use Python (a "safe" language).)
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C could be made safe, if you added runtime checks for array indexing, and disable pointer arithmatic except for arrays. Unless you're writing kernel-level code, you shouldn't use those features anyway. Or, you could just run it in a VM.
Performance could be enhanced by doing more things in libraries (e.g., a ramdisk used exclusively by one application (or a limited set of mutually-trusted/ing applications) could be supported entirely in userspace, with no context-switching necessary).
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The MIT exokernel does this. They've shown some impressive performance gains in certain apps, but the design is, by necessity, highly unconventional (the kernel provides extremely primitive abstractions, namely memory pages and raw disk blocks). And it just moves the bottleneck around. Depending on what you're doing, an extremely low-level kernel API could very well cause a lot more system calls than a high-level kernel API.
Or several mutually-trusting/ed intercommunicating apps could share the same address space, so no VM remapping would be necessary when switching from one to another, nor would a system call be necessary.
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You're essentially talking about threads. However, the problem is that you want sharing, but still want protection. Threads can corrupt each others memory, and that's unacceptable. Would you want your webbrowser to crash if your email client did as well? With a safe language, you get fine-grained control of who you trust. The only people you've got to trust are the ones you explicitly hand your object references to, and then only when dealing with that specific object.
(This would be kind of like a lightweight thread mechanism, but different threads could be loaded from different binaries.)
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Linux can do this exact thing via the clone() system call, but its of limited usefulness, because most of the time, processes do *not* completely trust each other.
I don't know if any of this would actually be feasible, though, since I haven't really worked on the guts of an OS for about 20 years.
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Its certainly doable (and indeed, has been done), but there are better ways now
A deep unwavering belief is a sure sign you're missing something...
that those innovations on older systems would have to be pretty much reinvented anyway, since the older machines were developed with closed or copyrighted codebases. Not to mention which, most of those "innovative" features have been superseded by the better features available on more modern systems.
Seriously, what features from the Atari systems are so great, yet have been overlooked in modern systems?
To celebrate the occasion of my 1000th post, I will post no more forever on Slashdot. Goodbye.
Good ideas
- unified name space (like Unix's single root / hierarchy)- filesystem as database (why do we have to put stuffs in two different things anyway?); the filesystem should support hierarchiecal as well as relational paradigm. one can put a SQL interface on top of it
- using a safe, higher level, garbage-collected, OO language (about time to kill C, damnit!), also as another poster noted, this can eliminate kernelspace/userspace separation
- everything is a file
- everything is a component
- Unicode
Bad ideas
- registry (at least the windows do it currently): it's like the 777 version of- XML for configuration (YAML is a better choice)
- package managers or installers (the OS should be modular and component-friendly enough to render this unnecessary; think a PC with pluggable PCI cards or USB devices; adding/removing software components should be as easy as plugging/unplugging hardware devices)
- resource fork/multiple stream or something like that (if i want two different content, i'll make two different record/file, thank you)
Not sure
- GUI at the lowest level?- using a safe, higher level, garbage-collected, OO language (about time to kill C, damnit!), also as another poster noted, this can eliminate kernelspace/userspace separation
/tables/CUSTOMER/001/name
/tables/ORDER/003/customer
/tables/CUSTOMER/$(</tables/ORDER/003/customer)/na me
/etc
So... your security model breaks utterly as soon as someone finds a bug in the *compiler*?
(Incidentally, what is your compiler or interpreter written in, and why would I use an OS that only supports one language?)
- filesystem as database (why do we have to put stuffs in two different things anyway?); the filesystem should support hierarchiecal as well as relational paradigm. one can put a SQL interface on top of it
With an efficient enough filesystem (ReiserFS?) you could do something like this:
(extra linebreaks for clarity)
# What is the name of customer #001?
$ cat
Joe Bloggs
# Who ordered order#003?
$ cat
001
# What is the name of the customer who ordered order#003?
$cat
003
The difficult bits of a relational database are the data integrity bits (transactions, atomic updates, that sort of thing), which *would* need extra filesystem support.
- registry (at least the windows do it currently): it's like the 777 version of
I'm sure parts of the Registry (HKEY_LOCAL_MACHINE?) are read-only for ordinary (non-Administrator) users; if you're right, though, the Registry is even worse than I thought.
IMO the main problem with the Registry is that it's in a few opaque binary files with a non-obvious structure; Unix configuration files are usually structured text, so it's easy to see whether a config file has become corrupted, possible to undo the damage, and possible to change everything with a simple text editor rather than having to invoke regedit. Unix config files are also split up sensibly (per-application) so they're easier to manage.
- package managers or installers (the OS should be modular and component-friendly enough to render this unnecessary; think a PC with pluggable PCI cards or USB devices; adding/removing software components should be as easy as plugging/unplugging hardware devices)
Hmm. So, how do you add software? Do you just copy a file-which-is-really-a-directory, MacOS-style?
If so, how do you suggest managing libraries? If every application has its own copies of all its libraries (or is statically linked), when someone finds a bug in, say, zlib, every program that used zlib needs an update. With separate library packages and intelligent dependency checking, you should only need to update zlib itself (and in a package management system, zlib should have been installed automagically the first time you installed an app which needed it).
If you want to be truely revolutionary, you should take the top-down approach and start with a solid object-model (with a clearly defined semantics), and only then start thinking about how to implement the rest.
BTW: anyone which dare to write a comparison between VMS's logicals and Unix's environment-variables? Are VMS logicals more secure? Wikipage Of VMS.
--
Simon Strandgaard
How can you have a great OS without such a tool?
I looked at the webpage and well... I saw nothing.
"Wouldn't it be cool if we could write an OS that's better than everything else out there. I want it to be radically different. Please join me & be brilliant & provide all the inspiration and drive to make me famous for heading this project".
my sig's at the bottom of the page.
Since we are on the subject of tags, putting a tag on every scalar datum seems like a waste of memory and address space, but putting a few tags on an array doesn't seem like a big deal. Instead of an array being , an array could be , and this triple could be set 1) when you dynamically allocate an array, and 2) when you "cast" the array by taking a subslice of it. The bounds checking can be coded efficiently by an optimizer that knows about loop variables and such.
I suppose you could do something like this in C++ with a template class and the proper inlining and such (is an STL vector reasonably efficient?), but I don't know if the compiler can optimize out the bounds checks. I would think you would have to make this kind of array a language feature rather than a template-class implemented language extension to get best efficiency.
Resources are represented in a tree form and you may only lock something if you have a compatible lock higher up the tree. The lock-modes are something like: NULL, Shared Read, Shared Write, Protected Read, Protected Write and Exclusive. Certain modes are defined as being compatible with other modes, i.e., protected write with shared read. The resource tree means that you can only lock a record for write if you have the file open for write. If you can't get a lock, you get forced to wait. However, you can implement code so the current lock holder is imformed there is a waiter so the holder can choose to release the locks.
Another neat thing is that anyone getting access to a lock can receive an attribute block which can contain arbitrary information. This block can be updated by any system with protected write or exclusive lock levels and is instantly relayed to other processes, whichever node on a cluster that they reside.
Of course, the lock system has access levels, so a user can't mess with system held locks.
It really gets fun though because the lock manager doesn't give a damn about what the resources refer to, so you can use it for all kinds of things.