Phantom OS, the 21st Century OS?

jonr writes "Phantom OS doesn't have files. Well, there are no files in the sense that a developer opens a file handle, writes to it, and closes the file handle. From the user's perspective, things still look familiar — a desktop, directories, and file icons. But a file in Phantom is simply an object whose state is persisted. You don't have to explicitly open it. As long as your program has some kind of reference to that object, all you need to do is call methods on it, and the data is there as you would expect."

Comments

Opera of the phantom

[mcgrew]

I skipped the Register article and went to the Phantom site, and I'm still puzzled. Somehow I get the idea that somebody's trying to snow somebody.

Q: [does phantom have] separate address spaces?

A: No. No! At this point you thought to yourself something like "than Phantom can not protect one application from another", and were wrong. Phantom is one big address space. But, nevertheless, everything inside is protected. Protection is based on a simple idea. Phantom is a big virtual machine. And this VM has no means to convert integer to pointer - due to this it is impossible to scan through address space and gain access to anything you have no pointer to. That's simple. And - yes, due to the absence of separate address spaces IPCs are really cheap in Phantom. And there are no context switches, which add effectiveness to the system. One can argue that VM makes system run slowly, but nowadays this problem is solved with effective JIT compilers, so we don't expect real degradation due to the VM. Moreover, the result of JIT compilation can be stored so usual Java-like startup penalty won't exist in Phantom either.

Memory in all computers is mapped to address space. I get the idea that these guys are programmers who don't really understand how the hardware works.

Q: File system?
A: Nope. Sorry. Nobody needs files in Phantom. All the operating system state is saved across shutdowns. Phantom is the only global persistent OS in the world, AFAIK. All the state of all the objects is saved. Even power failure is not a problem, because of the unique Phantom's ability to store frequently its complete state on the disk. The most unusual Phantom property is its hybrid paging/persistence system. All the userland memory is mapped to disk and is frequently snapped. Snapshot logic is tied with the common paging logis so that snapshots are done cheap way. From the application point of view it means that all the user documents or any other program state doesn't have to be squished into the linear filespace with the help of the serialization code, as it is in classic operating systems. Anything is kept in its internal, "graph of objects" form. This means that Phantom programs are much simpler and more efficient also. Opening text document in classic OS means reading file (transferring its data to specific place in process memory) and then converting its contents to program internal form (decoding and once more moving data), and just then - showing it to a user. Opening text document in Phantom means just executing some object's printMe() method - all the data is ready and available directly without conversion.

Nobody needs files? How, exactly, can I retrieve a document then? This FA is damned short on details.

Q: OS is based on VM - does it mean that not all the possible programming languages will be supported?

A: Yes. Say goodbye to C and Assembler. On the other side, everything is in Java or C# now, or even in some even more dynamic language, such as Javascript or even PHP. All these languages will be supported.

I really don't think I'm interested in this OS. TFA didn't point to a single thing about it that would lead me to want it, except for the state saving on shutdown, and I doubt seriously that's going to work. If your data are in memory and not the hard drive when it quits, you'll lose your data. If data are all written instantly to the HD, your PC will be slower than molasses in january.

Re:Opera of the phantom

[vadim_t]

Have you read About Face from Alan Cooper? He explains in that the concept of a file is horrible from a user perspective. Files are added as a concept because it is a hack and makes it easier for the programmer. A user in fact does not want to have say, "oh I have to save this?"

Heard of this idea, and disagree completely with it.

Continous autosave isn't a technically difficult problem. It could be implemented quite easily. But it would take one minor inconvenience, and replace it with several more difficult ones.

Ok, so you don't have to save anymore. Great. But now you have to deal with that you went to make tea, and your document now has your cat walking on the keyboard saved in it. You can't simply choose not to save, you have to figure out how many changes to undo to get the document to its pre-cat state. How many times do you have to press the undo button?

Same goes for extensive modificatons. Maybe you decided to drastically reformat the document, but then decide the idea doesn't look good after all. You can't choose not to save, you've either got to undo 50 times, or have created a copy before starting making the changes.

Here's another issue: since there's no save operation, the undo history has to be kept forever. This means that whoever you're sending the document to, if they're so inclined, can replay your writing process backwards to see if there was anything you changed your mind on. Or if using another document as a starting point, what was there before.

It also removes safety: I spend much time telling people that they can't easily break anything. With this system they can. Somebody who accidentally selects and overwrites the whole document will find out that even pulling the plug won't bring the document back. Now there's one excellent way of making a newbie really freak out. What if you intentionally or by accident write something insulting in the document? How do you make the program remove the record of it?

Here's another one: Imagine this sequence of commands: I type a long document, decide I didn't like the last changes, undo too much, and then press a single letter. Does in this moment the undo history become a tree, or do I lose the ability to redo the excessive undo?

Resuming: You remove one small thing, the need to explicitly save, and add the requirement of eternal undo (potential issues with embedded images here), requirement for the user to understand the undo system, requirement to design it in such a way that hours of work can be undone without getting RSI, add potential problems with disclosure of things that the user doesn't want to disclose, make it harder to do large experimental changes, and remove a way for an user to completely revert a change.

IMO this is too much of a mess for so little benefit.

IBM already did it

[ebunga]

The S/38 and AS/400 have done this since like 1980 in COMMERCIALLY PRODUCED systems.

Re:Doubt it.

[SerpentMage]

Frankly you are thinking like an old operating system.

How does it handle locking conflicts? Well, think about it, how do you handle locking conflicts in your program? That is your answer.

The idea from this Phantom OS is that you don't need to think about "paging", or "locking conflicts" etc. You only need to think about your objects that are serialized to the system. Contention? Well create a server process. Think Erlang...

Here is I think his link...

http://www.dz.ru/en/solutions/phantom/

Re:Screenshots...

[mrjb]

Screenshots can be faked: user@phantom$ But according to this page, it's about 90% unimplemented. Someone please tag the article 'vaporware'.