Linus on Amiga decision

amiga_dude sent us an article that has a ton of information about the confussion and questions surrounding the recent Linux Amiga QNX news that has been sprouting up. This one is a pretty good catch all piece with some Linux words as well.

Comments

Re:Information on Linux TCP/IP Stack

[Just Some Guy]

Holger Kruse seems to know what he is talking about.

To put this in context, Mr. Kruse developed Miami (Modem Internet for AMIga) and Miami Deluxe (a full-featured TCP/IP stack with routing, IP-NAT, etc. built in). More info can be found at Nordic Global.

I only mention this to say that Holger's not some half-read crackpot who's just spouting off - he really does know what he's talking about.

Why Amiga switched

[Bruce Perens]

The Amiga folks switched operating systems not because of any present technical superiority, but because of the future. If there's something we don't like about Linux, it gets fixed. If you don't like how QNX works, you're stuck. Even if we get the QNX source code, who will want to put lots of free work into this proprietary product? That's why they chose Linux - because it's evolving so much faster than proprietary systems.

I found the criticism of Linux' TCP/IP rather laughable, because I remember not very long ago one of the primary criticisms of Linux was that it didn't have TCP/IP. Whatever you don't like about Linux' TCP/IP implementation will be fixed soon enough. Meanwhile, it runs fast enough to saturate my 768/768 DSL while the Pentium 120 CPU is loafing along. I can wait a year for it to be fast enough to saturate a DS3. The criticism regarding other OS having work-arounds to interoperate with Linux applies to Linux 1.x (or other old versions), and of course those problems are long gone (along with the FIN_WAIT problem he mentioned). The criticism about lack of IPV6, etc., is bogus, he's not been keeping up with Linux' development.

Someday, Linux development will taper off and we'll switch to another system - maybe even a message-passing system like QNX. But the system we switch to will be free software, because of its fast evolution, not proprietary like QNX.

Thanks

Bruce

As the Ball Bounces

[eponymous cohort]

The new soap opera starring an OS which has been down on its luck that decides that if it just gets a makeover, and dumps its fiance for the hot, young penguin chick that everyone wants to be seen with, things will turn out ok.

what's "Amiga" about it?

[jetson123]

The original Amiga was a great machine at a great price. But what about the new (planned) one? It's a different OS, it's a different set of programmers, it's different hardware, it's different owners, and it's probably a different user community by now, too.

That's not necessarily bad. But what all this amounts to is that a division of Gateway is thinking about building a multimedia computer that uses some of the Linux kernel. The fact that it's called "Amiga" seems pretty incidental to me.

Re:Information on Linux TCP/IP Stack

[InvisibleCraterFunk]

Once you've read the page linked above you need to read this as well.

Re:I'm glad that they chose Linux

[Salamander]

>QNX is a horrible operating system. I wouldn't
>use it to run a toaster, much less a desktop
>environment

You again, tlewis? Why are you on this anti-QNX crusade, anyway? For a brief moment, I was wondering whether you work for a QNX competitor, but then I remembered from our last encounter that you don't have any OS or embedded-system experience so that seems unlikely. I can only guess that you enjoy trolling.

As I pointed out last time, different platforms are intended for different environments, in terms of both the "lower environment" of what the hardware provides and the "upper environment" of what the applications/users require. Your phrasing "...much less a desktop environment..." shows your bias; like many people, you seem to consider the desktop to be the whole world. This is just not realistic.

>Message passing is for wussies

Speaking of what's "for wussies" how much real programming have you done? Application-level programming is "for wussies" as far as I'm concerned, and that's all you ever seem to have done.

Message passing is not "for wussies" at all. Look under the covers of any supposedly non-message-passing system - even a processor/memory bus - and what you'll see are...messages! It doesn't make any difference that the messages are processed by hardware rather than software. Now, given that it's all messages in reality, what's wrong with passing messages that represent higher-level semantic concepts than "get" and "put"? Answer: nothing. Message passing is, in short, an essential part of computing.

Is explicit message passing implemented in software a good basis for an OS? Yeah, it's OK, if one understands its strengths and weaknesses. Message passing is good for supporting heterogeneous systems, long latencies, and robust fault detection/recovery, compared to memory sharing. Message passing can also suck like a black hole wrt performance. Efficient message passing is essential, as is an overall architecture that keeps the number of messages and/or time blocked waiting for messages down. Many message-passing systems (e.g. Mach) have sucked because they had layer after layer of overly-complex interfaces creating more message traffic, and were insufficiently parallel within each subsystem to tolerate message latencies. But it _can_ be done right. Did QNX do it right? I don't know, but I've heard quite a few comments leading me to believe that maybe they did.

As an aside, I have worked on both hardware and software versions of distributed shared memory. The latencies etc. involved present some very hard problems which to the best of my knowledge have not yet been adequately solved. I'm inclined at this point to believe that - until we understand the solutions better - anything inherently distributed is better off with explicit message passing than with a shared-memory paradigm on top of a translation to the necessary message passing.