Xv6, a simple Unix-like teaching operating system • Hacker News Board

Re: Xv6, a simple Unix-like teaching operating system

#71

Post by hnthrowaway0328 » Sat, Jun 08, 2024, 2:24 PM UTC

nickpeterson wrote: post #69

hnthrowaway0328 wrote: post #68

Earlier quoted context omitted.

I am reading the book, now that you mentioned. I only reach the part when David was hired by Microsoft though. Actually I'm super interested in his earlier works in Dupont and DEC as they paved the way. I took him as an inspiration. His “What I really wanted to do was work on computers, not apply them to problems.” rings so true with me, and he as a natural leader also makes me look up to him.

"Work on computers, not apply them to problems" feels like the kind of mentality that gets a lot of people into trouble :)

I think what he means is system programming, not application programming. But TBH I'm so sick of my DE job that I indeed don't care at all about business problems.

Sure we all need them for jobs, hey but that doesn't mean I have to love them. Would that impede my career progression? Sure, but as long as I can get into a system programming without being too close to business, I'm happy for life. Other people can climb the greasy pole, good luck for them.

Re: Xv6, a simple Unix-like teaching operating system

#72

Post by soraminazuki » Sat, Jun 08, 2024, 3:26 PM UTC

nialv7 wrote: post #12

Why Unix v6? Why teach with a 50 years old design? I feel to teach the fundamentals of an operating system, i.e. scheduling, IPC, address space management, a microkernel design would be better.

Why not? xv6 doesn't prevent you from learning about microkernels in any way. It's also a complete operating system with code that's friendly for beginners.

Re: Xv6, a simple Unix-like teaching operating system

#73

Post by pjmlp » Sat, Jun 08, 2024, 3:53 PM UTC

vkazanov wrote: post #60

pjmlp wrote: post #58

Earlier quoted context omitted.

Because it is travesty of what is effectively a microkernel architecture. A free beer UNIX clone won, that is quite different than any technical advantages. Even Android does the same with Binder IPC, since Project Treble.

Android, SteamOS, WebOS and all the numerous Linux-based projects, mostly show that the world needs a stable target platform everybody can do a meaningful contribution to (and then make sure nobody steals the work later). Linux literally ate the world with its POSIX-compatible open-source proposition. I don't have a single device without Linux at home, and this includes a NAS, 5 notebooks, 1 PC, a handheld gaming con…

Just wait until the Linux founding fathers are no longer around.

Try to write Linux POSIX code for Android, WebOS, and ChromeOS apps, and see how many normies will buy your wonderfull app.

Free beer ate the world, everyone likes free beer, even it is warm.

Re: Xv6, a simple Unix-like teaching operating system

#74

Post by pjmlp » Sat, Jun 08, 2024, 3:56 PM UTC

kragen wrote: post #21

nialv7 wrote: post #12

Why Unix v6? Why teach with a 50 years old design? I feel to teach the fundamentals of an operating system, i.e. scheduling, IPC, address space management, a microkernel design would be better.

a lot of people agree with you, which is why minix exists (though their source control system just fell offline this year), but none of windows nt, linux, os/360, and even really macos/ios are microkernel designs. sel4 and the other l4 variants are, and so is qnx, and linuxcnc runs linux under a microkernel, and xen is kind of a microkernel if you look at it funny, so we're definitely seeing significant mainstream us…

While Windows and macOS aren't pure microkernels, they certainly are much more in architecture than pure UNIX clones will ever be.

Re: Xv6, a simple Unix-like teaching operating system

#75

Post by justin66 » Sat, Jun 08, 2024, 3:57 PM UTC

hnthrowaway0328 wrote: post #35

I have ways wanted to understand the Windows NT kernel -- maybe the earlier versions as they are simpler. I heard the first version is close to VMS. Is it true? Is there any material on VMS? OpenVMS is open sourced but the version is too high.

Windows 2000 source code is out there in the wild (I expect newer versions have been leaked as well) and has even been used as a teaching tool.

Re: Xv6, a simple Unix-like teaching operating system

#76

Post by pjmlp » Sat, Jun 08, 2024, 3:57 PM UTC

sham1 wrote: post #70

pjmlp wrote: post #38

Earlier quoted context omitted.

That is how we end with students always cloning UNIX on their projects, instead of going alternative roots like Redox or SerenityOS.

The irony here is that both SerenityOS and Redox are UNIX-like. Of course in their design, they're not purely like most other UNIXen, but they also don't stray away too far.

They offer a POSIX like API on top, which isn't the same thing, as the key APIs, and overall system architecture, are something else.

Also mostly because as it happens in most hobby projects, people keep wanting to replicate GNU due to the existing software, thus keeping the UNIX cycle alive.

Re: Xv6, a simple Unix-like teaching operating system

#77

Post by pjmlp » Sat, Jun 08, 2024, 4:01 PM UTC

evil-olive wrote: post #53

nialv7 wrote: post #12

Why Unix v6? Why teach with a 50 years old design? I feel to teach the fundamentals of an operating system, i.e. scheduling, IPC, address space management, a microkernel design would be better.

> Why teach with a 50 years old design? > a microkernel design would be better. why re-hash a 30 year old debate? [0] 0: https://en.wikipedia.org/wiki/Tanenbaum%E2%80%93Torvalds_deb...

I guess because Tanenbaum was right after all, instead of microkernel processes, we got containers and kubernetes pods.

Re: Xv6, a simple Unix-like teaching operating system

#78

Post by monocasa » Sat, Jun 08, 2024, 4:08 PM UTC

pjmlp wrote: post #41

monocasa wrote: post #28

Earlier quoted context omitted.

Lion's Commentary on Unix is a classic tome on the subject, but unfortunately was illegal for quite some time. https://en.wikipedia.org/wiki/A_Commentary_on_the_UNIX_Opera...

The way it was handled only proves the point UNIX would never had taken off outside Bell Labs, if AT&T was allowed to sell UNIX the moment it stopped being a toy project for playing games.

Wat

Re: Xv6, a simple Unix-like teaching operating system

#79

Post by pjmlp » Sat, Jun 08, 2024, 4:20 PM UTC

monocasa wrote: post #78

pjmlp wrote: post #41

Earlier quoted context omitted.

The way it was handled only proves the point UNIX would never had taken off outside Bell Labs, if AT&T was allowed to sell UNIX the moment it stopped being a toy project for playing games.

Wat

The book was forbidden by AT&T from publishing, the moment AT&T got released from the ban to sell their research, in parallel to the BSD lawsuit.

It kept being shared via piracy across universities, until AT&T and other commercial UNIX vendors, eventually allowed the book to be published again.

https://en.wikipedia.org/wiki/A_Commentary_on_the_UNIX_Opera...

Had the book never seen the light of the day, in the alternative universe of a commercial UNIX, universities wouldn't have adopted UNIX as research material to feed the next generation of UNIX clone makers.

Re: Xv6, a simple Unix-like teaching operating system

#80

Post by samatman » Sat, Jun 08, 2024, 5:15 PM UTC

kragen wrote: post #23

RACEWAR wrote: post #11

What's a good way for autodidacts to fiddle through this?

[flagged]

While I also find the handle quite objectionable, I wouldn't say that "racewar" and "genocide" are words which can be freely exchanged without lack of meaning.

A review of the contributors, well, contributions, suggests a 9front connection.

They have a reputation for humor in very poor taste, but insofar as there's any sincerity to be found there, it isn't that of sincere genocide enjoyers.