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Phantom OS: Persistent Operating System

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Re: Phantom OS: Persistent Operating System

#61

Post by gizmo686 »

tomaskafka wrote: post #46
kstenerud wrote: post #8

This kind of system will suffer from the ratchet problem. A single bug that negatively impacts state is no longer fixable by rebooting. Instead, you have to format/reinstall. Unintended state becomes permanent, and upgrade paths constrained to the point where you must do intentional damage. I'd also be leery of fragmentation. The project is falling into the "simplification trap", where all it's doing is moving inhere…

This is what happened to my iOS install. Due to some problem (is it an exploit hidden somewhere among incoming messages?) my Messages app opens for 5+ seconds every time, and there is absolutely nothing I can do, except setting up a whole new iPhone from scratch (and hoping the problematic message win't get synced from iCloud anyway). On rooted Android I could clear corrupted app data.

Does Android even need to be rooted? The settings app on my stock Samsung has a clear data button for every app.

Re: Phantom OS: Persistent Operating System

#62

Post by anthk »

AnIdiotOnTheNet wrote: post #41
pjmlp wrote: post #36

I like the ideas in Phantom, even considering the negative comments, it is refreshing to see people having a go at OS design that isn't just blindly making yet another UNIX clone, because apparently we can't get enough of them.

Indeed. So many people seem to be brought up with an almost religious indoctrination that UNIX[0] is the end-all be-all of OS design. [0] By which of course we mean Linux.

- GNU's Not Unix.

- Persistent OS'es are a thing since BOOTP boots for example with OpenBSD or alpine on "diskless" mode.

Thank Unix for that for being so simple to implement.

Re: Phantom OS: Persistent Operating System

#63

Post by offmycloud »

How do you handle backup and restore on a system like this? If the snapshots are at the OS level, and there is cross-app commingling of data objects, how can you restore the state of a particular application or object (formerly "file") without breaking everything? How do I restore a single document or a single contact in my address book?

Re: Phantom OS: Persistent Operating System

#64

Post by AnIdiotOnTheNet »

anthk wrote: post #62
AnIdiotOnTheNet wrote: post #41

Earlier quoted context omitted.

Indeed. So many people seem to be brought up with an almost religious indoctrination that UNIX[0] is the end-all be-all of OS design. [0] By which of course we mean Linux.

- GNU's Not Unix. - Persistent OS'es are a thing since BOOTP boots for example with OpenBSD or alpine on "diskless" mode. Thank Unix for that for being so simple to implement.

Are you sure you know what 'persistent' means in this context? Because I cannot see how network booting leads to the kind of persistence we're talking about. In fact, you seem to be describing technologies that help in implementing the exact opposite.

Also, you've missed the point of the Linux comment. I'll spell it out: typically people who revere UNIX in the way described have never in their lives used a UNIX system other than Linux (unless it was MacOSX+, of course). Is that relevant? Not really, that's why it is a footnote.

Re: Phantom OS: Persistent Operating System

#65

Post by strlen »

webmaven wrote: post #57
strlen wrote: post #47

Question, how does this compare/contrast to “image based persistence” as used by e.g., most Smalltalk and certain Lisp based VMs?

It is equivalent, as are the pre-XML MS Office file formats which were essentially dumps of the document in memory.

“Every normal man must be tempted, at times, to spit upon his hands, hoist the black flag, and write(2)/WriteFile a struct to disk.”

Re: Phantom OS: Persistent Operating System

#66

Post by mahesh-hegde »

Findecanor wrote: post #25
mahesh-hegde wrote: post #18

I remember reading about another, pretty old, microkernel OS which had persistent processes. It was probably a capability based OS. Anyone know what that was?

You are probably thinking of EROS https://en.wikipedia.org/wiki/EROS_(microkernel) > But there have been several others also based on similar ideas, such as Mungi. In recent years, there is Twizzler, intended for NVRAM. https://www.youtube.com/watch?v=0Ix5DYKxzLI >

Yeah it was EROS.

Re: Phantom OS: Persistent Operating System

#67

Post by timka »

ralferoo wrote: post #11

I'm not sure this actually solves the real problem that people have. Sure, reboots are annoying and pretty much all current OSes could be improved in this regard. Back in the 90s, it's interesting that SunOS supported live kernel upgrades, so at the same time the kernel on disk was updated, the running system was also patched so it would act the same way as-if rebooted, but without any disruption to the live system.…

The plan is (was?) running any JVM stuff on their VM.

Also, IIRC Dmitry was thinking about embedded systems applications at least back in 2011 when he was giving a talk about PhantomOS at HighLoad++ conference in Moscow.

Re: Phantom OS: Persistent Operating System

#68

Post by timka »

webmobdev wrote: post #21
hsbauauvhabzb wrote: post #7

Earlier quoted context omitted.

What about some middle ground? I’d like my IDE to remain constant between reboots, my browser to some degree is already (if it crashes, it reopens all current tabs on start, which is effectively the same). I would have thought some clever hacks on an existing kernel would be reliable enough rather than an entirely new OS just for one feature, though.

Isn't that what Hibernation offers on Windows?

Sort of like that but you don't have to wait until all your 16Gb of RAM are written to disk. AFAU, Dmitry found a cheap way of making consistent snapshots of a running system.

BTW, there was a thread on HN relatively recently where someone mentioned that the hard part of hibernation is not restoring the RAM state but bringing all hardware into the right state at boot. That's why hibernation has been so problematic on Linux.

Re: Phantom OS: Persistent Operating System

#69

Post by igouy »

daitangio wrote: post #59
kstenerud wrote: post #8

This kind of system will suffer from the ratchet problem. A single bug that negatively impacts state is no longer fixable by rebooting. Instead, you have to format/reinstall. Unintended state becomes permanent, and upgrade paths constrained to the point where you must do intentional damage. I'd also be leery of fragmentation. The project is falling into the "simplification trap", where all it's doing is moving inhere…

Yes, I have a similar feeling in SmallTalk (i.e. Squeak or Cincom) A corrupted image is difficult to fix, and you end up saving the code on a "parcel"/package and reload it on a clean image. Static image is indeed a nice feature I like.

Save code in a code archive.

Create a working image from a clean image + code archive.

Sanity prevails.

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