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Comment by dfc | Hacker News Reader

"Your job is being a professor and researcher: That's one hell of a good excuse for some of the brain-damages of Minix."

Linus Torvalds' post to comp.os.minix newsgroup.

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We're all well aware of the Usenet flamewar 20 years ago.

What has that to do with Minix now?

not everyone is aware:

http://news.ycombinator.com/item?id=3683984

If something is very successful, it doesn't mean it is very good and nothing can replace it. The world is currently divided into many school of thoughts, and only time will tell which kernel design is going to win the war. Also, there has been growing hatred towards Linux with its bloated kernel and eating all the RAM!

That's because many people have no idea how to even read the memory usage stats in Linux.

This.

http://www.linuxatemyram.com/

No "kernel design is going to win the war." Just like you will never find a "one size fits all" shoe. Different problems require different solutions.

What's the point of having memory if the OS isn't going to use it?

So that applications can use it?

If anything is bloated, it's typical linux userland. The linux kernel, with uclibc, busybox, dropbox, and other userland tweaks, can fit onto an embedded router with 4MB flash and 16MB ram.

Linux caches in RAM pages of files it reads. It will evict them at the drop of a hat if it needs to.

Sadly, no matter how many blog entries appear on the subject, people still expect to see free ram, and think linux is bloated when they don't see any.

If you don't like that behavior, I don't know if any OSes leave "free" ram untouched. They might call it free though, even when it's used by the OS for caching.

On the issue of microkernels vs monolithic, I prefer microkernels for their elegance in theory. If one appears with performance in the ballpark of linux, that glibc supports and that will run linux userland with no problems, I'll switch. I will not, however, give up functionality in the name of ideology.

I'm given to understand that Debian and Arch linux have GNU Hurd live CDs out there for people who want to run it. I don't really know much about the OS, but does it meet your requirements?

Hurd makes Minix look like a rock-solid production OS by comparison.

That's because people and tools look at the wrong values.

    $ free -m
                 total       used       free     shared      buffers     cached
    Mem:          2009       1491        518          0          466        363
    -/+ buffers/cache:        661       1348
    Swap:         1992          0       1992

Here, you want the number 1348, which is the "free" memory you have, not the number "518" which at first glance is the "free" memory.

If you're think of this as a Linux vs Minix 'war' then you are looking at it the wrong way. Minix is intended for research/education. Its not going to replace Linux because they do different things.

I didn't intend to sound the way it seems i sounded. Sorry for that! Btw, the focus of Minix 3 has changed and it is no longer intended just for research/education. Minix 3 was publicly announced on 24 October 2005 by Andrew Tanenbaum and it is comprehensively redesigned to be usable as a serious system on resource-limited and embedded computers and for applications requiring high reliability.

Not anymore:

"It was only with the third version, MINIX 3, and the third version of the book, published in 2006, that the emphasis changed from teaching to a serious research and production system, especially for embedded systems. A few of the many differences between MINIX 2 and MINIX 3 are given here.

Going forward, we are making a serious effort to turn MINIX 3 in an industrial-grade system with a focus on the embedded market, especially for those applications that need high reliability and availability."

http://www.minix3.org/other/read-more.html

Okay, I wasn't aware of the Minix 3 redesign, so I stand corrected on that. Thanks for updating me!

But I'm fairly skeptical about how much use (if any) Minix is getting outside research and education. Aren't there already widely deployed HR/HA OSs that target the embedded market? What real advantages does Minix have over something like VxWorks?

Maybe by being open source.

Does VxWorks come with source code? I guess this might be critical to some type of applications.

For me the positive is to see more microkernel architectures getting spread.

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