Messages in this thread | | | Date | Mon, 21 Jun 1999 22:39:05 -0700 (PDT) | From | Jonathan Walther <> | Subject | Its just MULTICS (Was Re: Some very thought-provoking ideas about OS architecture. |
| |
Eric, there is nothing new about this. What you are describing is a stripped down, clearly conceptualized MULTICS. Please stop spamming us. I do however, agree that MULTICS is the future. There were so many lessons in it that have been clearly ignored.
Jonathan Walther
On Sun, 20 Jun 1999, Eric S. Raymond wrote:
> (Please copy any replies to me explicitly, as I'm not presently subscribed > to the linux-kernel list -- it's not practical when I'm spending so > much time on the road.) > > Gents and ladies, I believe I have may have seen what comes after > Unix. Not a half-step like Plan 9, but an advance in OS architecture > as fundamental at Multics or Unix was in its day. > > As an old Unix hand myself, I don't make this claim lightly; I've > been wrestling with it for a couple of weeks now. Nor am I suggesting > we ought to drop what we're doing and hare off in a new direction. > What I am suggesting is that Linus and the other kernel architects > should be taking a hard look at this stuff and thinking about it. It > may take a while for all the implications to sink in. They're huge. > > What comes after Unix will, I now believe, probably resemble at least > in concept an experimental operating system called EROS. Full details > are available at <http://www.eros-os.org/>, but for the impatient I'll > review the high points here. > > EROS is built around two fundamental and intertwined ideas. One is > that all data and code persistence is handled directly by the OS. > There is no file system. Yes, I said *no file system*. Instead, > everything is structures built in virtual memory and checkpointed out > to disk every so often (every five minutes in EROS). Want something? > Chase a pointer to it; EROS memory management does the rest. > > The second fundamental idea is that of a pure capability architecture > with provably correct security. This is something like ACLs, except > that an OS with ACLs on a file system has a hole in it; programs can > communicate (in ways intended or unintended) through the file system > that everybody shares access to. > > Capabilities plus checkpointing is a combination that turns out to > have huge synergies. Obviously programming is a lot simpler -- no > more hours and hours spent writing persistence/pickling/marshalling > code. The OS kernel is a lot simpler too; I can't find the figure to > be sure, but I believe EROS's is supposed to clock in at about 50K of code. > > Here's another: All disk I/O is huge sequential BLTs done as part of > checkpoint operations. You can actually use close to 100% of your > controller's bandwidth, as opposed to the 30%-50% typical for > explicit-I/O operating systems that are doing seeks a lot of the time. > This means the maximum I/O throughput the OS can handle effectively > more than doubles. With simpler code. You could even afford the time > to verify each checkpoint write... > > Here's a third: Had a crash or power-out? On reboot, the system > simply picks up pointers to the last checkpointed state. Your OS, and > all your applications, are back in thirty seconds. No fscks, ever > again! > > And I haven't even talked about the advantages of capabilities over > userids yet. I would, but I just realized I'm running out of time -- > gotta get ready to fly to Seattle tomorrow to upset some stomachs > at Microsoft. > > www.eros-os.org. Eric sez check it out. Mind-blowing stuff once > you've had a few days to digest it. > -- > <a href="http://www.tuxedo.org/~esr">Eric S. Raymond</a> > > The Bible is not my book, and Christianity is not my religion. I could never > give assent to the long, complicated statements of Christian dogma. > -- Abraham Lincoln > > - > To unsubscribe from this list: send the line "unsubscribe linux-kernel" in > the body of a message to majordomo@vger.rutgers.edu > Please read the FAQ at http://www.tux.org/lkml/ >
- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.rutgers.edu Please read the FAQ at http://www.tux.org/lkml/
| |