QNX RtP 6.2 World Preview

Jason writes: "OSNews is running an exclusive preview of the brand new version 6.2 of the QNX realtime operating system. The article is going through the installation process, the Photon user interface (lots of screenshots included), the internals, and the advantages and disadvantages of the OS as a desktop system. QNX RtP 6.2 is expected to be released for free (for non commercial usage) before March."

Comments

Why would anyone use

[wiredog]

A real time OS as a desktop system? I've worked with embedded/real time systems and performance in that world is different from performance in the desktop and server worlds. QNX has a nice looking GUI, but who would need it in an embedded or real time application?

Real time OS's Have Issues with performance on the desktop, just as desktop/server OS's Have Issues in the real time space.

Re:Why would anyone use

[jayant_techguy]

Ya that pretty true, but QNX as they say, was built for people who wish to know some more about real time os'. and it does that job pretty well :)

Re:Why would anyone use

[chrisatslashdot]

From the article:
QNX RtP is serving as the self hosted development platform for QNX-based internet appliances and other QNX embedded applications.

Re:Why would anyone use

[boris_the_hacker]

I think the point of the GUI is to allow for a self contained system in which to develop products using QNX. This is a nice idea as it allows you to compile, run, test, debug rather than compile, transfer, run, debug [remote/local]. Where the transfer stage adds yet another stepping stone in the development cycle (ok for large changes, but if you are tracking down a small bug it's a PITA).

From the article it seems like the tools and apps that are for QNX RTP are there to make the developers life less painfull (eg. the media application) and it's not for a general purpose desktop - and why can't developers have a nice GUI?

Just my 2 pence.

Regards, Chris

Re:Why would anyone use

[corrosiv]

1 - self hosted development: it is generally intended to be the embedded developer's desktop system, not a general purpose desktop system

2 - GUIs are frequently used in embedded/realtime systems. Factory control systems, health monitoring & analysis, PDAs.

My $0.02 (Canadian)

Re:Why would anyone use

[Sloppy]

Real time OS's Have Issues with performance on the desktop

Yeah, but the main "issue" they have is that they are so damned fast that users think it must be a trick.

What's good for RT, is good for everyone.

Re:Why would anyone use

[Arandir]

QNX has a nice looking GUI, but who would need it in an embedded or real time application?

Unix geeks demanding CLI-only interfaces aren't the only people that use embedded or real-time systems.

Scenario A) An embedded device controllable by the enduser: Gas pumps, POS terminals, ATMs, PDAs.

Scenario B) A realtime system with a non-realtime front end: medical scanning systems, manufacturing control systems.

A million more scenarios exist. Embedded RTOS aren't only for unseen automobile smog sensors.

Re:Why would anyone use

[Wumpus]

Funny? Maybe. True? Nope.

An RTOS can't make any design tradeoffs that will make its behavior unpredictable. That rules out swap and memory overcommit right off the bat. How is that good for everyone?

You do realize that if your DVD player is running at a high priority on a RTOS, then nothing is going to get CPU time when it's busy working its IDCT magic. This is a good thing in an embedded system, because people don't like it when their movies pause occasionally because the OS wants to do some housekeeping, sync the disk, update the clock on the front panel...

But what if you're running your DVD player on a 200MHz Pentium? Most likely, you'll freeze your system, because the high priority process won't be able to keep up, and will use 100% of the available CPU time. Embedded systems have a known hardware profile - desktops don't.

Re:Why would anyone use

[mangu]

nothing is going to get CPU time when it's busy working its IDCT magic

What you are describing is windows, not a true RT system. I once started developing a real-time data processing system in NT, and found I had to set the inner loop in my program to "real time priority" in order to keep up with the data coming in. The result was that I lost the mouse and keyboard. The only way out was to set the inner loop to yield to other processes when its calculation was done. This, effectively, amounts to rewriting the kernel low-level scheduler.

In a true real-time system, I would be able to set the mouse and keyboard processes to run at given intervals, while still having my data-handling routine able to digest what came in.

Fortunately, my story has a happy ending: I found out that Linux has a good enough scheduler to run my program without data loss, even if it's not a true real-time OS. But I toyed with the idea of using QNX for a while. Gave up when found out how much it costs.

Re:Why would anyone use

[uninet]

From my experience with QNX, I think there are a lot of useful purposes of using QNX on the desktop (not that I do, I use Linux/X11/KDE). First, a light installation of QNX can run really well on an older system such as a 486 DX4 100 in my case (I used the 1.44 "Amazing Demo" on that on). It's amazingly snappy on such a system too!

Also if you go with a full QNX install (which is just a 90 meg iso), you get a decent web browser, RealPlayer, dev-tools, and IIRC a root-less version of X. In other words, QNX Photon really could be a very nice GUI for embedded "webpads" or low-end desktops that aren't quite ready to be retired yet. Since QNX has gnu tools and X11, it also isn't an entirely bad desktop on more modern systems either...

-Tim

Re:Why would anyone use

[Wumpus]

What you are describing is windows, not a true RT system.

What I'm describing is based my experience writing some real time applications on QNX, in the last few years. The QNX documentation is available on the web, and the system is free for non commercial use. Download it, compile an application that sets its scheduling algorithm to SCHED_FIFO and its priority to the shell's priority+1,and goes into an infinite loop, run it, and see how responsive the system becomes. You don't have to take my word for it.

The only way out was to set the inner loop to yield to other processes when its calculation was done. This, effectively, amounts to rewriting the kernel low-level scheduler.

Huh? This amounts to not hogging the CPU when you don't have to. This is good practice under any OS, and doesn't even resemble rewriting the scheduler. Not even from a distance, on a dark foggy night.

The problem with "real time" priority under NT is not that bad code will lock up your machine if you tell the OS not to interrupt it. The problem is that the system can't guarantee that a real time task will get the CPU in a bounded time when it needs it (in response to an interrupt, for example). That's the difference between a RTOS and a non real time OS.

In a true real-time system, I would be able to set the mouse and keyboard processes to run at given intervals, while still having my data-handling routine able to digest what came in.

That is simply incorrect. For your keyboard and mouse "processes" (drivers, most likely) to be useful to anybody, the OS has to wake up a user process to handle mouse and keyboard events when they're available. If you tell the OS to give a higher priority to another process, NOTHING is going to interrupt that process until it yields. The assumption is that you know what you're doing, and that you really reallly need the CPU, or bad things will happen (bad, as in people will die, in some cases).You can't afford to have heuristics like "if a process had the CPU for too long in the last second, switch to another task. Let's all be nice and share!".(Actuallly, QNX does have such heuristics, but by running SCHED_FIFO you effectively disable them for the SCHED_FIFO task).

And that's only half of the picture. The other important element of real-time performance is that if your low priority task (your window manager, for example) is busy doing something, like drawing a bitmap on the display, and the system gets an interrupt that's served by a real time task, the OS will immediately switch to the real time task, leaving your pretty picture half drawn for as long as it takes to handle the high priority task. If you get 1000 such interrupts per second, it'll take some time for your window manager to finish drawing that bitmap, and, yes, the system will feel sluggish, but that's by design.

I won't even get into discussing throughput vs. latency issues.

Fortunately, my story has a happy ending I found out that Linux has a good enough scheduler to run my program without data loss, even if it's not a true real-time OS.

Good - I'm happy for you. I bet you can't compile a kernel while your code is running, though - not without causing it to miss deadlines, and not on a stock kernel, in any case. Linux really isn't a RTOS.

Re:Why would anyone use

[TimoT]

Realtime audio processing with realtime modification via a GUI. Virtual Synthesizers ? Playing really sucks if you get a click once every few seconds because the audio process was swapped in a few ms too late and you can't use buffering to counter this because it adds latency. If the latency is more than about 5-10 ms then the "feel" of playing will start to degrade.

QNX goes back a *long* way

[InterruptDescriptorT]

Do any Canadians (perhaps only Ontarians) remember the ICON computers they used to have in elementary and high schools? The ICON, also known as the 'Bionic Beaver', was a computer manufactured by CEMCorp (Canadian Educational Microprocessor, IIRC) that was meant to bring data processing and computer skills to thousands of high-school students.

The design of the machine was interesting--intelligent nodes running an 80186 connected by ArcNet to a central server node--but they ran a version of QNX. I remember the slightly different set of commands than we are familiar with in UNIX: for example, to go up a directory, it was 'cd ^', files could be deleted with 'zap', and commands could be easily run on remote nodes by prefixing the command with [nodenum].

It was on this machine and OS that I cut my teeth in C, 80x86 assembly and basic networking concepts (I wrote a small multi-node chat program using the virtual circuit calls in QNX), and as such I was always have very fond memories of it. Thanks for letting me reminisce. :-) (BTW, if anyone has one and is planning on getting rid of it, I'd gladly take it off your hands.)

Re:QNX goes back a *long* way

[gbrandt]

That would probably have been a derivitive of QNX 2.x. We used QNX 2.x exclusivley at a company I worked for. It was our desktop system from accounting to engineering. All running on ARCNet.

Since then QNX has moved up in the world. QNX 4 has full posix compliance and is very much like a normal *NIX. 6.x is so much like *NIX on the command line, that you can barely tell the difference.

Re:QNX goes back a *long* way

[Anonymous Coward]

I believe that we had some Unisys machines running some varient of UNIX (possibly QNX) early on in grade school (here in Ontario). There was no mouse, instead we had a trackball on the upper-right corner of the keyboard and two keys labelled "Action" on the either side near the top. Does anyone else remember these?

Re:QNX goes back a *long* way

[pacx25]

I believe that we had some Unisys machines running some varient of UNIX (possibly QNX) early on in grade school (here in Ontario). There was no mouse, instead we had a trackball on the upper-right corner of the keyboard and two keys labelled "Action" on the either side near the top. Does anyone else remember these?

Re:QNX goes back a *long* way

[InterruptDescriptorT]

Yup, that's the ICON. The trackballs were always in such bad shape, partially because my 'Hat Trick' clone was very trackball-intensive. :-)

Anyway, the last year I remember them was about 1991--they were replaced with 'modern' 386s around that time.

Re:QNX goes back a *long* way

[SuiteSisterMary]

Ahhh the Icon. With the built in trackball; I remember the movie maker app, and the 'choose your own adventure' real-life sim type thing. With Danny, I think his name was, the pot-head.

Re:QNX goes back a *long* way

[NoMoreNicksLeft]

This is very interesting to me, the computer of which you speak. Any idea where someone could buy one? And yes, I have the arcnet network to hook it up to.

But to think, 80186's in a desktop computer, networked with arcnet, running a non-mainstream OS? I'm already in love. I just hope they get along with my TRS-80 Model II.

Re:QNX goes back a *long* way

[MatriXOracle]

Ahhh the ICON's. Those things were great. There were several variations of the ICON. The ICON I's were huge things with a built in montitor/keyboard/trackball/cpu all in one unit. The ICON II's and III's had more in common with the original iMac's: CPU and monitor in one unit, and the keyboard/trackball a separate piece. Those things used 386 processors.

I actually really liked the trackballs on those systems, it was really easy to move the ball around with your hand and press the Action button with your thumb.

And anyone remember Offshore Fishing? That game was great.

Re:QNX goes back a *long* way

[B1]

Our school had them (Oakville Trafalgar High School... class of 92).

I fondly remember the 'ipaint' program on the ICONS--that program where you could create vector-based animation by drawing key frames. Also, there was that really cool chemistry lab program.

Most of the kids at school grudgingly used them--I remember it had some sort of 'PC Compatibility' mode, and they tried to teach kids WordPerfect on them. Wordperfect under the DOS compatibility mode was brutally slow though--felt a bit like wading through a pool of bubblegum. I tried to stay away from them as much as possible.

I had one friend that waded through the reference manuals for the ICON, and actually did quite a bit of development under them. That was like him though--always wanting to figure out what made things tick. While most of us were content with DOS, he was mastering UNIX, QNX, C, and this wierd thing called 'Usenet'. I can honestly say he knew more about the ICON than anybody else at the school, including the Comp. Sci teacher/sysadmin.

There's no doubt there was some inner beauty to the ICON--certainly, it was a very interesting network architecture. Alas, this was all hidden behind horrific applications and a cumbersome user interface.

I think the ICON is what you get when you let the government design computers. All the right features, on paper they should have been great...terrible execution though.

Re:QNX goes back a *long* way

[mini me]

Does anyone else remember these?

I remember them well. They had somewhat of a GUI and the cursor was controllable with a trackball. I do remember that the later incarnations of the server system used a computer that could run both DOS and UNISYS applications.

Of course I was only like 8 years old at the time so the details are a little sketchy.

Re:QNX goes back a *long* way

[tzanger]

Do any Canadians (perhaps only Ontarians) remember the ICON computers they used to have in elementary and high schools?

Yup. Used 'em in Grade 7/8 IIRC at Stanley Park Senior Public in Kitchener, ON. (Grade 7 would have been '89?) -- I got booted out of the room after a while for dicking around at the command prompt they boot up with, trying to get in to something I had no idea about at the time.

I've got one now (had two) -- they cut off the keyboard though, and I've got to figure out what pins go where (the connector's gone) but I'd love to boot it up again. You've got the specifications exactly right: 80186 (basically a controller version of the 8086, it includes the PIC, DMA, PIT and a few other of the 82xx-series of support chips in the processor package itself), I think about 640k of memory (weird staggered-SIPP package), arcnet, EGA or VGA display. Gray case that boots up blue and spends 99% of its time displaying blue background. :-)

I bet you could get something like ELKS running on it without much trouble.

Man... I remember the *sound* of the room they were in. the server(s) (I believe we had two, one for each double row of ICONs, about 20-24 ICONs per server) with physically ENORMOUS hard drives and fans and fans and fans... in a room with no sound suppression. It sounded like a large colo facility does today, I bet.

Re:QNX goes back a *long* way

[Prince Caspian]

Oh yeah, I remember Icons. We used them at Waterloo Oxford DSS for Grade 11 Comp Sci class as late as '93, when I took the class. The classes consisted of self-directed units on the fundamentals of programming using BASIC.

I remember I would complete the two week lessons in a day or two and spend the rest of the time getting into trouble, such as the time I recreated the entire login screen, ASCII art and all, in a BASIC program. Using a friend's account, a few of us installed it all around the lab and waited for people to log in at which point their passwords were logged to a file. The only problem was we had nowhere to go after that, so the program just displayed some lame message asking the user to reboot their computer. Almost everyone did, except for the guy whose computer backed towards mine. Needless to say I was caught, chastised, and never hacked anything again. ;)

Re:QNX goes back a *long* way

[bolverk]

See cleannorth.org if you're interested in these things. We get tons from the school board here at every event. They're still trying to get rid of them.

If you want to try to make arrangements to get some from us, I urge you to (we're in boonie-land Canada, though).

-Dan

Re:QNX goes back a *long* way

[DrXym]

I programmed QNX 2 for 3 years for use in medical diagnostics instruments and I have to say it was the worst, most nasty OS I have ever used. Yes it did multitasking, but the tools were diabolical, the compiler was a joke, it had an ugly OpenLook-like UI, it was proprietary and not in a good way and it cost a lot of money. I have no idea how it ended up inside mission critical software because it looked like a hobbiest OS gone bad. It didn't even have a decent editor and I had to port MicroEmacs to it. It's only saving grace was it was fast, realtime and had some natty messaging protocols.

Quantum made a very wise and sensible decision with QNX 4 (what happened to 3?) to go Posix since it made the OS tolerable and almost Unix like. Still, by that time I was getting restless feet and I moved onto bigger and better things. I still wonder about the company I left - I bet there are poor souls working there who have to fix problems in QNX 2. May god have mercy on their souls.

Re:QNX goes back a *long* way

[panthro]

Offshore Fishing! Except that in French schools in Ontario it was called Pêche En Haute Mer. IIRC, the whole system was translated into French, but I had gotten in trouble so many times fooling around with their DOS computers that they watched me like a hawk and I never got to see the QNX CLI.

Re:QNX goes back a *long* way

[irix]

Indeed. I went to an Ontario high school and gradualted in 1993. By 1993 we had a lot of macs and PCs, but in the earlier grades we used them a lot.

We did elemntary programming using logo and later Pascal using the ICONs. I never remember doing any C with them, but by the time I started learning C it was 1992, so I was on to PCs by then.

Re:QNX goes back a *long* way

[xenyz]

Offshore fishing was great, but what I remember was a game called 'Upstairs / Downstairs', one of the first graphical networked multiplayer games. Our school wore out a bunch of those trackballs playing that game. :)

Re:QNX goes back a *long* way

[Anonymous Coward]

Wonderful machines, though I must confess to being an ex Cemcorp employee! Both the ICON I and II were based on 80186 processors, beginning with the ICON III, standard UniSys PCs were used. The networking was modified ArcNet - I believe that the drivers used non-standard voltages, so they won't be compatible with standard ArcNet equipment. Unfortunately I scrapped my last Icon (actually Lexicon server) two years ago...

Re:QNX goes back a *long* way

[Anonymous Coward]

If it was the Icon systems, then you were using QNX :)

Re:QNX goes back a *long* way

[corrosiv]

QNX3 was simply QNX2 + protected mode

Re:QNX goes back a *long* way

[Anonymous Coward]

You are sapposed to have it fail with an incorrect password message, and then run the actual login routine.

Re:QNX goes back a *long* way

[Anonymous Coward]

ICONS! I got to use those things for 2 years at NDDHS for grades 11/12. The machines were intended as learning platforms for our programming class, but most people just played the games. I still remember sitting for long minutes watching my Turing ?3.x? session load and execute my code. Never realized they ran QNX though, we were never allowed to leave that fancy menu system they had.

Re:QNX goes back a *long* way

[twinpot]

Action keys were also on the Unisys B20 series, which ran BTOS (CTOS clone).

A microkernel that doesnt suck

[Koim-Do]

I generally know that the Neutrino microkernel is faster than Mach, but have anyone ever made (and published the results of) performance comparision between Neutrino, Mach and L4 ?

Re:A microkernel that doesnt suck

[Animats]

Yes, but you have to register to read it.

First Impressions

[jaavaaguru]

As someone who's never used or seen QNX before but has seen many other OSs, I like the first impression this gives me (going by the eye candy). Some questions I need to know the answer to:

• Does the calculator have a paste feature? This is something really lacking in KDE's one. And it bugs me when I can't be bothered adding two file sizes together (or typing the sizes into the calculator)
• Will the interface always be as consistent as it is in the screenshots? - the Macs at school always had consistent user interfaces. With the advent of Microsoft Domination we witnesed horrible UIs that were exremely inconsistent. They can't even make their own apps have the same UI as their OS.
  These shots of QNX make is seem like they've missed out all the bad features of other OS's and included all the good ones. I like it.
• Does the web browser perform as fast as the other ones that are currently in use? (IE, Konqueror, Mozilla, Opera) and can it render the majority of pages that Konqueror can?

These are just some things that people notice.

Re:First Impressions

[ergo98]

You can always get Opera if you want.

Re:First Impressions

[Arimus]

Eye-candy and RTOS?

To me there are alot more important issues in a RTOS than the eye-canday... response speeds, QoS guarantees, robustness etc.

And robustness and pretty UI's usually don't go well together as alot of pretty UI's break the KISS rules...

Re:First Impressions

[linatux]

last time I checked, the KDE Calc could select/paste the same as most any X app.

Re:First Impressions

[jaavaaguru]

You're right! :-)

I always feel though, that the OS's native browser (the built in one) should be good though. Sometimes I just want to get on and do work without having to get extra software. I know that's bad for the industry, etc, but c'est la vie. From experience, the later versions of Konqueror meet this requirement - being just as fast as Opera on the same system (Hmmm... Opera has definitely got an good thing going there), but I've yet to see another OS where this can be experienced. I've heard Mozilla is available for it also but don't see any mention of it on Mozilla's site (on a top of the range PC you don't tend to notice the speed differences and the UI/standards support is more of an issue)

Re:First Impressions

[jaavaaguru]

Hmmm... Eye Candy.

I know people think that that is one of the least important things in QNX, but if I'm gonna be sitting in front of my PC for >14 hours a day I want at least two things out of it:

• Reliability
• Useability

Please note, I left "A Life" out of the list deliberately ;-)
Correct me if I'm wrong here - I only started reading about this today - QNX's main plus point is reliability, right? This is what makes it such a good server OS. This article is talking about it as a Desktop OS (look, he mentions FAT32 and NTFS). Why not go the whole way to becoming a popular desktop OS and make eye candy too? there's no reason it can't be there but be kept to a minimum so that it's reliable.

As for the calculator...
I couldn't get it to work in KDE 2.2-x (i think x is 13) from the RedHat 7.2 distro. I know it used to work though. If not being "bleeding edge" means doing without the paste function in my calculator I think I'll install Mandrake.

Re:First Impressions

[fredrik70]

"QNX's main plus point is reliability, right? This is what makes it such a good server OS."
It's not a server OS really, it's a RTOS, much used for embedded stuff

Re:First Impressions

[kindbud]

If you had read the review, you would have known that the Voyager web browser supports a pluggable HTML engine, for which Opera has made a plugin. So yes, it renders HTML at least as well as Opera 5. :)

Re:First Impressions

[XPulga]

I never used the KDE calculator. I recommend you learn bc .

Usually you'll start a session on an xterm and make calculations as needed, but

echo "34 * (7 + 5000)" | bc

works too. Better than bc, only a real HP48G within reach. And yes, I would kill for a Palm calculator application with 1/3 of the HP48G functionality.

Re:First Impressions

[Russ Steffen]

You are wrong about KDE's calculator not supporting cut and paste. If you right click on the calc's "display", the value is copied to the clip board. If you middle-click on the display, whatever is on the clipboard is pasted in.

Re:First Impressions

[jaavaaguru]

Thanx. I have that command on my system but I didnt know about it. It's gonna be quite useful :-)

And being a GNU utility, QNX will probably have it too :-)

And as for the guy below, being able to copy & paste isn't that useful if you dont let people know how to do it. Right click to copy... That's not particularly intuitive.

Who is this reviewer?

[djweis]

Does he have any background in embedded systems? He seems about as qualified as me reviewing pacemakers. I think prettiness is overrated in a system like this.

Re:Who is this reviewer?

[dhuff]

"He" is a she - Eugenia Loli-Queru. Eugenia is Editor-in-Chief of OSNews.com. Before moving to the U.S. she was a web-designer in the U.K., ported more than 80 Linux/Posix/DOS applications to BeOS and founded the BeUnited BeOS Development Movement in April 2000.

As for a background in embedded systems, I'm not sure - but she is certainly more qualified than you suggest, having experience with many OSes incl. BeOS, AtheOS and FreeBSD among others...

Re:I gave up on QNX...

[Koim-Do]

Maybe their newsgroups are intended to answer QNX, rather than FreeBSD questions ?

Please consider this hypothesis. you can easily excersise it by posting a valid *QNX related* question to their newsgroup.

BTW, as the whole FreeBSD kernel runs in a single address space, and supervisor privilege, a faulty device driver may crash your (otherwise stable) kernel.

QNX vs. Joel On Software

[gbrandt]

Here is a banner example that sometimes rewriting software does make sense. Since 1985, QNX has rewitten thier OS three times, first QNX 2.x, then QNX 4.x and now RTP 6.x. All rewritten from scratch and all better than the last.

A simple OS for mom

[Pengo]

Maybe this is it. Show her how to dial up with the modem, use launch the email client and web client and find a version of AIM and there you go. I imagine that because it's UNIX(like), you should be able to run it non-priviliged without problems or fear of someone else messing it up.

Has anyone tried running this on slow hardware? (Such as a P133 or something w/32 megs ram?) How does it fare?

Re:A simple OS for mom

[InsaneCreator]

QNX 4 (the bootable floppy version) ran just fine on my old k6 200 + 32MB RAM. I guess it should work quite well on your computer, too. But I'm not so sure about Mozilla, sice it has pretty high system requirements to run normally. But I think the OS itself and the apps that come with it should rune just fine. After all, QNX is used in VCRs and similar devices which do not have an athlon/pIII inside them

Re:A simple OS for mom

[GooberToo]

My understanding and one of the common grips about QNX for the desktop is that QNX is POSIX-like and not UNIX-like. Remember, POSIX is not UNIX. Small yet distinct difference. Perhaps this has changed from years back but I know that used to be a very common misunderstanding and complaint once someone tried it out as a desktop system.

Re:A simple OS for mom

[nhavar]

The slowest machine I've set this up on is a P75 w/32 megs of ram. It worked fine although with the video card I had it couldn't get to higher color depths. Amazingly I didn't have to do anything to configure the modem, sound card or NIC and everything ran fine. Really helped a novice get on the net quick and play a few games that they like to play. No need to spend $600 for a new PC just so someone can surf the net and get mail and play card games, dust off the old PC and slap QNX on easier than a Mandrake install.

Re:A simple OS for mom

[Sj0]

So far, I've run this on a Cyrix M333(it really runs at about 250MHZ on a socket 7 architecture), a 333MHZ PII, a 550MHZ mobile celeron, and it's been almost as fast as BeOS on all those machines(BeOS was the fastest modern OS I've ever seen -- it ran sweetly on a p90, which is more than I can say about Windows "we won't install on anything less than a p200" ME.)

Re:A simple OS for mom

[Ivan Raikov]

My understanding and one of the common grips about QNX for the desktop is that QNX is POSIX-like and not UNIX-like.

QNX 6.something is now available for download from QNX's web site -- I installed it last weekend and played around with it a little bit. It appears that most of the user utilities are taken from NetBSD, and the configuration file tree is structured very closely after BSD. The system library claims POSIX compiance, and the kernel claims conformance to the realtime POSIX API.

Re:A simple OS for mom

[Anonymous Coward]

QNX is POSIX-like and not UNIX-like.

Yeah, I can see how mom might have a problem with that.

?

Re:A simple OS for mom

[Anonymous Coward]

I've been doing something similar, with a Dell that has a pre-MMX Pentium 120 pushed up to 133. QNX is great, and can make the machine quite usable.

There is a caveat: QNX6 does not have a normal swap implementation, though this is 'coming someday.' The default install uses a very large disk cache, which means 32MB is the minimum to *boot,* but you can't use the system in that state.

A helpful QSSLie tipped me off to the cache size adjustment procedure, which is also a great introduction to the microkernel/embedded philosophy. Interested parties can have a look here.

If you want to do more than run Voyager, I'd suggest something with a bit more horsepower than a P133. (Anything in the ~200MHz+ range should be great; look to the Audrey and iOpener CPUs as hints.) When it comes to browsing, the flash plugin in 6.1 really needs more cycles than a P133 can offer, and there's no quality adjustment to speed things up. The GIMP is a definite exercise in patience on that machine...

Very Cool

[TRoLLaXoR]

Having run QNX RtP 6.0 and 6.1, I have to say I'm waiting with baited breath.

6.0 was excellent, but patch B killed TCP/IP networking. Either that or the driver for my NIC was bad. Performance was good on even 32 MB RAM.

6.1 was an improvement mostly in the details: small little useful features were added, driver support was added, performance tweaks were added (try playing 32 MP3s simultanesouly on a Windows 2000 box with just 32 mgs of RAM!), and overall it was what one would expect from a secondary release.

If 6.2 is anything to 6.1 like 6.1 was to 6.0, I'd say the QNX guys had found the right pace, although it'd be nicer to have these updates every 6-9 months instead of every 9-12 months.

I'm running QNX RtP 6.1 on a dual Pentium Pro system, each proc has the 1-meg L2 cache and is overclocked to 233MHz, and 32 megs of RAM (going to a gig soon).

Hello Point... you've missed it.

[MosesJones]

Its a real time operating system for embedded devices. The PC based platform is for development to help you rather than plugging directly into the RS232 port of your dev kit.

The questions you ask are nothing to do with an RTOS but looking at it from the perspective of "Oh look a Windows competitor" this is NOT in the same market as even WindowsCE, although there is some overlap. The PC based platform is to aid development, it can be stripped down to a delivery box but this is not for Joe Sixpack PC user.

The real question is "Can anything else run in a couple of Megs of RAM..... or less" and have guarenteed delivery times on tasks. The answer for Linux and MS-Windows is NOPE.

THIS IS NOT A DESKTOP OS.

Sorry for shouting but people should

a) Read the article

b) Understand that MS-Windows and bloatware are not the most interesting market in the world.

c) Realise that cut and paste on a VCR is a silly idea.

Re:Hello Point... you've missed it.

[ergo98]

You're totally wrong. QNX Neutrino is a bottom to top OS from tiny machines to clusters of high power hardware. QNX has pushed their OS on thin-cients, Internet Appliances, etc, it isn't just for embedded monitoring hardware. Indeed the big QNX push is "QNX on a floppy" that basically turns a PC into an IA.

Re:Hello Point... you've missed it.

[dilvish_the_damned]

&nbsp&nbspc) Realise that cut and paste on a VCR is a silly idea.

But cut 'n paste on a development envirenment is not a silly idea. Its almost mandatory. Hell, you probably have cut 'n paste in your VT without even a GUI.

Re:Hello Point... you've missed it.

[Anonymous Coward]

The answer for Linux and MS-Windows is NOPE

I agree with you as far as M$-Windows goes, but don't diss Linux!

If you strip Linux kernel down to a bare minimum it fits in 512 MB of RAM. Want real-time delivery times, patch in RTLinux.

This is a huge market for Linux. Embedded app developers are paying extraordinary sums for closed stuff like QNX when they could get all the benefits for free. Quite frankly I'm disappointed in /. for promoting closed source.

Re:Hello Point... you've missed it.

[be-fan]

Umm (RtP == RealTime Platform) *is* a desktop os.

Re:Hello Point... you've missed it.

[Anonymous Coward]

you stupid cunt

Re:Hello Point... you've missed it.

[Anonymous Coward]

"QNX on a floppy" is not the big push. If fact that's a totally different version of the OS.

Re:Hello Point... you've missed it.

[ergo98]

The point is that QNX is showing users how much functionality they can fit in a tiny amount of space: Basically they're repositioning themselves as an IA backend company (and I think they'll be very successful at it in the near future).

Re:Hello Point... you've missed it.

[Anonymous Coward]

Yes it is. I've used QNX RtP extensively and can safely say that it meets the requirements for being usable as a desktop OS by all means. I've used it to write documents, browse the web, ftp files, watch movies, listen to music and play games (like Quake 3).

It also does all of this better and more seamlessly than Windows or Linux.

Re:I gave up on QNX...

[Anonymous Coward]

Please consider this hypothesis. The poster said nothing about posting a FreeBSD question to a QNX newsgroup. His QNX question was not answered so he ended up using FreeBSD instead, dumbass.

QNX

[niftyeric]

I used QNX a while back and really liked it, although I could *never* get my sound card working. It found everything else just fine. It'll be interesting to see how much more (if any) hardware it supports now. I had trouble compiling a few things, but nothing that I couldn't live without. Plus, it comes with Doom and Quake 3 (at least the older versions did).

Re:QNX

[GreenHell]

Unless anything is new since the last time I used it, Quake III only works with a Voodoo-based graphics card (not even sure what version of Voodoo... probably 3)

Anyways, I tried it back with v4, liked it but had no use for it, almost put it on one of my machines when v6 came out, but it still had that nice little isa network card problem that had plagued me before (3c509b, when it comes to non-mainstream OS's it causes more problems then it's worth, just ask any BeOS user)

Re:QNX

[GreenHell]

Sigh.... I really should follow my own advice some time and RTFA (read the fine article)...

"[...] and 3D support seems to still only work with Glide and Voodoo3."

Well, guess that answers that...

Re:QNX

[Anonymous Coward]

Quake III seems to work quite fine on any card with OpenGL, such as my NVidia Geoforce2. Quite well too, I might add.

Re:QNX

[ext]

Quake3!? I thought it only ran in Linux,win ans mac!
Maybe you meen quake1?

Re:QNX

[niftyeric]

Nope, it came with Quake 3. I don't know if 6.2 does, I haven't looked in it.

QNX and the desktop

[Mighty-Troll]

QNX is a good project for throwing on that old machine or for use as an embedded system (it's currently the operating system of my cable modem).

I'm waiting before I install on my main machine, however. I've been following the progress of QNX for quite a few years now and I'd like to say it's coming along quite nicely, just give it more time.

Oh and don't praise it or knock over it's desktop appearance. Desktop is about the last thing I look for in an OS (if it's that bad I can always create a better way myself.. hrmf).

Spelling Nazi

[Multiple Sanchez]

If you're going to mount your high horse and pick at the tiniest of grammatical nits, at least spell "grammar" correctly.

And what do you mean, "if it's an embedded OS, because a hard drive would defeat the purpose"? Systems with hard disks need OSes, too.

Re:Grammer Nazi

[corrosiv]

The original QNX OS was released as QNX2 in the early 1980s. I don't know the story on QNX 1 - perhaps it was the specialized product that inspired them to attempt a general purpose realtime OS. In the late 1980s/early 1990s it was rewritten as QNX4 to implement many new ideas (and improve on old ideas). This was labelled QNX4. QNX4 gave the world a better, more UNIX-like development platform and more UNIX-like behaviour via POSIX. Not long after QNX4 came Neutrino. This was to be a specialized kernel for deeply embedded applications while QNX4 was to be more general-purpose realtime. The entire QNX4 application base has now evolved to run on Neutrino, so now this is all packaged together like QNX4 was and is called QNX6 or RealTime Platform.

Steve

QNX: longtime (semi) embedded player

[RatOmeter]

As has been pointed out in other post(s), QNX has been around a long time. In fact, they first called it Qunix, but AT&T (Bell Labs) slapped'm down on that long ago.

I'm heard first-hand testimonials attesting to its bullet-proof operation which makes it a great choice for controlling machinery. You can also install, de-install just about any service/driver/app without needing to reboot.

Where I work, we make large, expensive automated testing equipment (lotsa horsepower, moving parts, other dangerous shit). We wanted to eval QNX about 3 years ago, but they told me they only provide free eval copies to their $100K plus customers. We make about 7 to 12 machines per year; they slammed the door in my face.

Now (and their previous free non-comm version) that the've got a pkg I can use to eval, it's too late. Even if we were still in a position to choose QNX, I doubt we'd easily forget our previous snubbing.

Re:QNX: longtime (semi) embedded player

[Kalabajoui]

Many companys are eager to make ammends for customer service screwups to keep up a good reputation. You might do well to extract your vengeance upon QNX by calling up their customer service department, explaining your grievance, and then asking them to do what their conscience dictates they should do to set things right. This strategy doesn't work 100% of the time, but I've had good luck with it on numerous occasions, with remedies ranging from discounts to free services and merchandise. The worst thing that could happen is they refuse to deal with you; in which case you just take your business elsewhere. Of course this is all assuming you would ever have a desire to use their products for future projects.

Re:Grammer Nazi

[Anonymous Coward]

It's written from scratch. Same basic concepts, all new code. Neutrino (which QNX6 was originally called) is a completely seperate product from QNX4.

VMWare

[Anonymous Coward]

Does anyone know if the new version runs in VMWare? The old one didnt. :-(

Amiga

[Snowfox]

A reminder that this was originally going to be the OS used for the new Amiga hardware, before Amiga up and went in a strange, new direction which didn't involve new hardware.

I guess this is a peek at what the new Amiga could have been. It doesn't look as nice as 3.9, though the underlying technology is pretty neat.

Re:Amiga

[MartinG]

Wow.

You have actually managed to include the word "amiga" in a post to slashdot without immediately being moderated down and told to "let the amiga die peacefully" and other equally tedious replies amiga fans usually get.

congratulations :-)

QNX is underrated...

[christurkel]

QNX RTP really is a fine little OS. Runs great on older machines, has a nice GUI and a wide range of applications for it. The built in browser, Voyager, is pretty good. Oh ya and there is a version of Quake III for it.

Some hangups.

[be-fan]

QNX RtP has tons of potential, but there are lots of things holding it back as a desktop OS:

1) Lack of unified VM/buffer-cache. The size of the disk cache is fixed rather than dynamically adjusted depending on need.

2) Lack of proper swapping. Since swapping kills embedded apps, RtP lacks good swapping. Use of swap has to be explicitly coded into the app, and was implemented as sort of a hack to allow gcc to be self-hosted.

3) Real-time scheduler. The hard-real time scheduler might be nice on an embedded system, but on a desktop system (where fairness takes a back seat to user-percieved responsiveness) it doesn't work well.

4) Crappy disk subsystem. I don't know if this problem has been fixed in 6.2 (I doubt it) but RtP has a really slow disk system. The IDE drivers have issues and the filesystem is ancient.

Some of the numbers that RtP shows aren't as impressive as they could be. 0.55us context switches sound great, but Linux can do switches on that order as well. Still, RtP is a great system. QNet, in particular, is very featureful, and Photon totally destroys X in every area except maybe 3D support. It has superlative network transparency, a good (fast) widget set, incredible fonts (courtesy of BitStream's FontFusion) and a nice, lean, architecture. If QSSL would port Photon to Linux (which wouldn't be that hard, given that both are mostly straight POSIX) I'd pay to run it.

Re:Some hangups.

[Anonymous Coward]

posix hits tons of boundaries for shit like this. when it comes to things using hardware, posix plays little or no role. without even considering drivers, it'd still be difficult unless it was written specifically to be ported, with hooks everywhere for different types of messaging and such.

Photon doesn't even come close to destroying X in anywhere close to every area. first you'd have to understand what X is. "X" isn't XFree86, XFree86 is XFree86... however to compare it to XFree86 you'd have to do some extensive research to see what features are turned on and of course that doesn't even include widgets since that's part of the window manager/library/app under X.

Re:Some hangups.

[Sloppy]

Real-time scheduler. The hard-real time scheduler might be nice on an embedded system, but on a desktop system (where fairness takes a back seat to user-percieved responsiveness) it doesn't work well.

Huh? Fairness is the enemy of responsiveness. There is no back-seat. On an RT system, if you have your UI run at a higher priority than your cpu-sucking apps, you get responsiveness that Windows/Linux users can only dream about.

Re:Some hangups.

[Anonymous Coward]

QNX RtP has tons of potential, but there are lots of things holding it back as a desktop OS

You mean like the fact it's an embedded OS?

Re:Some hangups.

[Anonymous Coward]

hahaha, meanwhile I'll run something useful.

Re:Some hangups.

[Anonymous Coward]

"On an RT system, if you have your UI run at a higher priority than your cpu-sucking apps, you get responsiveness that Windows/Linux users can only dream about."

Yet another person who has no idea what real time means. Real time simply means that the worst case latency is bounded. You can have a real time OS with a worst case latency of 2 minutes; it would be a RT system, but its responsiveness would be more of a nightmare.

Re:Some hangups.

[be-fan]

Traditional schedulers have several problems with GUI programs.

QNX RtP's scheduler, a straight priority-driver round-robin affair, allows a high priority process to run whenever it becomes ready, even if it is preempting the foregroung GUI process. Its a very static scheduler, which means it doesn't take into account the myriad of issues that result in good UI response.

Traditional UNIX schedulers try to be fair to each process, penalizing CPU-bound processes and giving better response to I/O bound processes. This, too, has flaws. A CPU-bound GUI process can get penalized when an I/O bound background process (such as a compiler) can get boosted. The scheduler doesn't take into account which process is in the foreground when making decisions.

The two best schedulers I've seen for desktop systems are Windows NT's and BeOS's. Both treat GUI scheduling as an integral part of the system and take issues such as which is the foreground process into account when making decisions. This is not as "clean" as the UNIX way of doing things, but results in much better user-percieved responsiveness.

Re:Some hangups.

[be-fan]

1) Actually, POSIX plays a huge role. The X server is nothing more than a big program that accesses the system through the standard kernel APIs (barring DRI, of course). Since both the QNX kernel and the Linux kernel offer similar functionality through a similar API, it shouldn't be any harder to port Photon than any other major app. The only hangup I can think of would be the differing messaging schemes, but that's a very narrow and concrete issue to solve.

2) For all practical purposes, X is XFree86. We are talking desktop OSs here and there is only one X server that is of any consideration as a main GUI for an OS and that is XFree86. I don't care what SGI has made IRIX's version of X do, it doesn't run on Intel machines and is thus irrelevent. Isn't life great when you have 99% market share? That said, I challenge you to point out one thing that X does better than Photon, aside from 3D,

Re:Some hangups.

[be-fan]

Obviously, somebody didn't read the docs. QNX RtP is designed to:

"[scale] seamlessly from the leanest consumer device right up to the largest distributed SMP systems."

Re:Some hangups.

[Pseudonym]

I disagree in part.

1) Lack of unified VM/buffer-cache. The size of the disk cache is fixed rather than dynamically adjusted depending on need.

I can see why you say this, but in practice I can't see this as a problem. The size of the disk cache is increased with the number of devices mounted. On the other hand, separate caches mean you can implement different buffer cache policies depending on the device. (You can imagine, for example, that flash memory could use a very different write-back policy than disk.)

Separation of mechanism and policy is something that pervades QNX, and is arguably the key to the flexibility of modern operating systems (compared with the inflexibility of monolithic systems). Even the QNX kernel, Neutrino, is actually a microkernel built on top of a nanokernel. The nanokernel implements mechanism, and the microkernel implements policy.

2) Lack of proper swapping. Since swapping kills embedded apps, RtP lacks good swapping. Use of swap has to be explicitly coded into the app, and was implemented as sort of a hack to allow gcc to be self-hosted.

It's not a hack, but I do think it's unfortunate that it's not "officially" supported. It would make more sense to:

• Determine at boot or configure time whether you want swapping or not.
• Assuming that swapping is enabled, applications which are granted I/O privileges get all their memory non-swapped. This is non-negotiable. (Why? Because if you have I/O privileges, you can install an interrupt handler. Your interrupt handler had better not access swapped-out memory.)
• Again assuming that swapping is enabled, any other applications may selectively lock all or part of their memory. (This may require other privileges.)

3) Real-time scheduler. The hard-real time scheduler might be nice on an embedded system, but on a desktop system (where fairness takes a back seat to user-percieved responsiveness) it doesn't work well.

You really need a hybrid (and I don't mean RTLinux). Desktop systems need real-time. BeOS users can testify to this. Also, there are new applications such as serving streaming media and ATM routing which really need real-time. Even burning CDs really needs real-time to do properly.

Admittedly, you probably don't need to implement an ATM switch on your desktop machine, but you might on your server. Real-time scheduling might be a really good thing here.

4) Crappy disk subsystem. I don't know if this problem has been fixed in 6.2 (I doubt it) but RtP has a really slow disk system. The IDE drivers have issues and the filesystem is ancient.

That's true.

Re:Some hangups.

[be-fan]

I can see why you say this, but in practice I can't see this as a problem. The size of the disk cache is increased with the number of devices mounted. On the other hand, separate caches mean you can implement different buffer cache policies depending on the device. (You can imagine, for example, that flash memory could use a very different write-back policy than disk.)
>>>>>>>>>
Seperate caching policies can be implemented with a unified cache as well. The thing is, that on a desktop machine, the usage of disk cache can vary wildly. At one minute, the user might be running a disk-intensive program like a compiler, and the next moment they might be running a program that doesn't touch the disk, like a game or raytracer.

You really need a hybrid (and I don't mean RTLinux). Desktop systems need real-time. BeOS users can testify to this. Also, there are new applications such as serving streaming media and ATM routing which really need real-time. Even burning CDs really needs real-time to do properly.
>>>>>>>>>>
I think you need soft-realtime, but you have to be flexible about it. Hard-realtime, with its viscious demands on timing, is really not appropriate for an environment where you might sometimes want to "break the rules" and give a process some extra time in order to make the desktop more responsive to the user.

Re:Some hangups.

[Pseudonym]

Seperate caching policies can be implemented with a unified cache as well.

True, but I wouldn't like to maintain or debug the code that does it.

The thing is, that on a desktop machine, the usage of disk cache can vary wildly. At one minute, the user might be running a disk-intensive program like a compiler, and the next moment they might be running a program that doesn't touch the disk, like a game or raytracer.

By "disk-intensive [...] like a compiler", I assume you're referring to VM performance. Correct me if I'm wrong (I may well be), but shouldn't pages written out to swap or read in from swap not hit the buffer cache at all? (They might if you're using a swap file rather than a dedicated swap device, of course.)

Games and raytracers aren't disk intensive only because they do their own caching, not relying on the OS to get policy right. Games can be several CDs in size, and are only managable because they're easily partitioned into levels.

Renderers (including raytracers) aren't so lucky. A Pixar-level scene may have up to 2Gb of gzipped geometric data and 10Gb of texture data, and you don't know in advance what's needed when. Needless to say, professional renderers spend a lot of lines of code managing cached data very carefully.

Internet Appliance != Desktop

[MosesJones]

And an internet appliance is a minimal spec box, possibly without a hard-disk that has a cheap screen (possibly touch screen). Again its not aimed at the Microsoft market so the original point still holds. The cluster stuff is for specific tasks and not the desktop. The point is quite simple. Not every OS out there is meant to run the same way as windows, there is a wonderful world out there of OSes that are aimed at different tasks, all too often Slashdot is concerned, and its readership only aware, of the MS style of market.

OS/390, AS/400, EPOC, QNX etc etc etc... well cool OSes for paticular circumstances.

Re:Internet Appliance != Desktop

[Anonymous Coward]

An Internet Appliance is most definately a desktop. The whole point of an internet appliance is allowing people to do without the complexity of a full PC, but still accomplish what they need to. Is my Sparc5 not a desktop, just because it has a slow CPU and small disk?

Re:Internet Appliance != Desktop

[ergo98]

Sure it's aimed at the MS market! Just like BeOS would love to replace your desktop, QNX would love for you to use their OS as your desktop. The reality is that the world is such that that is almost possible: With more and more apps being web based, the reality is that QNX with Opera or some other reasonably full featured browser can be satisfactory for most users. Of course QNX is a full OS (it just happens to put stability in front of everything else), meaning that technically there is nothing that can't be done, and of course right now you can do most anything you'd want on QNX.

Re:Grammer Nazi

[ImaLamer]

Yes, as people pointed out... I didn't spell "Grammar" right.

I never said I was the Spelling Nazi, thankfully we have some here on slashdot.

Timothy is poo, AC is offtopic

[Anonymous Coward]

Well Timothy might not be excited by it, but I think the Pogo is tres cool. Basically it's a phone/PDA- but here's the catch, it's got full web access (faster than 56k they claim) and it's all done in Flash! Very pretty! It's just been released in the UK today, but I imagine it'll be in the States and worldwide soon enough...

Alas, QNX!

[fm6]

Never heard of these machines, but as you describe them, their design makes a lot of sense. At about that time, I was working for Convergent Technologies, which mostly made systems that ran CTOS. Like QNX, CTOS had a message-passing architecture, and was thus very well-suited to distributed computing. QNX has always struck me as more elegant than CTOS, though.

When I left Convergent, I ended up working with 8086 and 80286 systems -- and found the limitations of MS-DOS really painful. QNX was then being marketed as a DOS alternative. They claimed to be able to do serious multitasking on 8 mhz systems. I actually found that claim credible, not to mention tantalizing. But I never got a chance to test it. The QNX license fees were just too high.

It's a real pity QNX wasn't in the picture when IBM was shopping around for a PC OS. History would be very different!

Moving away from desktop.

[Xapp]

"However, I somewhat got the feeling from the new version that QSSL is moving even more far away from a "desktop QNX." " QNX as a company has no interest in the desktop market and all that it entails. (eg. tech. support, updates, etc.) It is mainly concerned with providing a realtime system for industry as well as providing a decent developement environment for the software that will go into those systems.

0.55us context switches

[Anonymous Coward]

Is there a way to increase the time between context switches (from 0.55us)? I understand that QNX cx are very lean, but we're talking about 18000 cx per second (compared to 20ms=50/s for Win95, 10ms=100/s for NT/Linux (non-pre), 3ms=333/s for BeOS). If each cx takes 50-80 CPU cycles, we're consuming an enormous amount of CPU cycles just for multitasking, resulting in poor desktop performance (but excellent embedded performance). Heck, even the embedded stuff I work with is 1ms=1000/s and its sufficient.

two words from the cdr community

[Anonymous Coward]

buffer underrun

Re:two words from the cdr community

[Anonymous Coward]

more words from the cdr community:

scsi
burn-proof
just-link

Re:two words from the cdr community

[Anonymous Coward]

even more words.

burn proof etc do not write discs that are playable on all cd reading hardware if the bufn-proof is actually used (there is a gap which is unnoticed by modern hardware, but older audio cd players suffer)

scsi is no magic solution either. I've had scsi for ever and you can still get buffer underruns if you do stupid things with both linux (2.2 and 2.4 using cdrdao or cdrecord) and windows (just by breathing too loudly)

0.55us is very good

[Anonymous Coward]

This time is not the time between context switches. It is the time required to perform one context switch.

Windows performs 50 switches per second, but appears to take on the order of 200us to perform a single context switch. That means that windows spends about 10 ms in context switches.

QNX would spend 25us in context switches. This means that it can do a lot more, say a 1000, thats only 1.25ms spent in switches, and a much smoother communitcation between threads.

Re:0.55us is very good

[Anonymous Coward]

Got it. Thanks for clarifying that the switch itself takes 0.55us. So, on a 700MHz (average P3), that means a context switch takes 385 clock ticks (on a RISC one instruction per clock tick). So how many cs/sec do we get?

Re:Grammer Nazi

[Anonymous Coward]

Others have pointed out that you mispelled "grammar"; I'll add that you picked the less serious nit. How about this:

Consult the screenshots to get a feel of how the sidebar looks like.

This foul, little sentence actually contains two errors! Either "...to get a feel for how the sidebar looks" or "...to get a feel for what the sidebar looks like" would be correct. The former is preferred, as the latter is unnecessarily verbose.

context switch

[Anonymous Coward]

What is done in a context switch? Because I can interrupt the processor at each 0.8us I wonder from were the 55us come from. Is it just interrupt overhead?

Re:context switch

[Anonymous Coward]

A context switch occurs when the CPU is interrupted and exchanges the running address space (the 'context') for another, eg: one process for another or a process to the kernel. Most OSses have the kernel space partially visible above the end of the user space (in the top 1GB, usually) so this doesn't require a context switch. There are several reasons for a cx, the most common is quantum expiry (the program has used too much time and another will be given a chance to run).

In a process-process cx (such as expiry) the kernel saves the running processes context (its registers, IP and in some cases the TLBs) and loads the next one. This memory transfer takes more CPU cycles and contributes to the delay. The rest is the expensive (on x86, anyway) re-loading of the page table and caches. Obviously the new process shouldn't be able to read the old processes memory, so the caches and TLBs must be cleared. They then get re-loaded by the next processes page faults.

That's the main time sink in a context switch.

why bother?

[Anonymous Coward]

QNX is lame and it's not even worth running on the desktop for any real reason... this is nothing more than an attempt to save some company money with bug testing in something that'll never be a real OS...

GUI

[SilentChris]

I haven't seen this OS before, but I wasn't surprised to see it had a primarily Windows 9x-style GUI. Shouldn't we be up to something new? (Even XP, which I sorta like, uses the same old Start button motif).

A Seriously cheap way to get 'net connected!

[FyRE666]

Since you can now pick up old Compaq Internet Appliances for as little as $39 dollars (233/266mhz, 32MB RAM, 32MB Flash, 800x600 TFT screen), I'm sure QNX could be hacked into one of these to make a very usable and cool looking little browser/terminal! I believe it was also used in the original iopener devices, which had similar specs.

It's a pity Be crashed out of the embedded market really; their BeIA operating system was amazingly efficient. We were developing a system using the Compaq devices as shop terminals, (the versions we had included ethernet ports) and even when running telnetd, ftpd, the desktop (tracker) and the Opera browser, they were using like 18-20MB of their 32MB RAM! Pretty fast too, they could play Flash 4 animations at a decent speed even with pretty slow processors. An interesting thing about the Opera browser on the BeIA platform was that it gradually leaked memory, losing a little every time a new page was loaded. Once the device was over 90-92% memory usage, the browser was killed, and respawned. However, the user wouldn't notice this, as when the browser was killed, it left its image on the screen, then reloaded the last page visited so it was just a slight delay!

where are the pics??

[thetechfreak]

im on the site and would luv to see the eye candy..but all the pics are shown as dead links for me

Re:I'm Jewish

[Anonymous Coward]

i was impressed by your "day in the life" posts and so I did one of my own, but this time about Jamie.

check it out.

are you really part jewish?

-txr

Re:QNX goes back a *long* way [OT]

[SerpentMage]

Yeah I do remember the ICON. I graduated from Highschool in 87. When we first got them in 84 nobody knew how to use them.

I remember we all wanted to get ROOT user access since this would give us super powers. The teachers had no clue as how to use them and just looked at these monsters like monsters. Then one day a teacher was clueless and let some kids watch over his shoulder and to see the ROOT password. Within a couple of hours the entire network came crashing.

The problem was that nobody knew what they were doing, students included, and the "hacker" copied the entire operating system from the root directory to his directory. But instead of a copy it was a move. The network came to a screeching halt for a week since nobody knew what to do.

After that everyone was more nervous... Ahhh... The good ol' days.

But what was cool about the ICON was even in 1984 it worked in a multi-tasking environment. Not like the networks of C64's or Commodore Pets with its muppet network system.

Ok I am OT with this posting, but let me go really OT.

Before the ICON we had Commodore Pets networked together with a serial cable using the muppet network. The muppet network was not intelligent enough to figure out who was writing what and when. Therefore if somebody wrote to the printer or the disk while someone else was already doing something the two would get joined. So you could end up with a printout that was the concatnation of two documents. To get around this we had to yell "Writing", "Printing" and "Done". At the same time somebody had to go to the chalkboard and draw an X.

Wow, now things simply work!!!!

Hey f00!

[Sir Richard Pump-a-l]

I see you is postin' at -1 again!

HA!

All my hardware is supported.

[rasactive]

Maybe I'll make the move from linux to an OS with even LESS supported software. :)

I have no authority on the matter, but it looks like a pretty cool OS.

Disk speed is fixed under 6.2

[Anonymous Coward]

There is now support for UDMA 66 and UDMA 100 under 6.2

QNX had a totally broken low-level disk copy cmd

[U96]

I remember using one of those ICONs and making a mistake while using a diskcopy command. I was attempting to make an archive of a floppy disk's image onto the hard drive, but instead it made a low-level copy of the floppy onto the hard drive. Suddenly the 20Mb HD was convinced it was a floppy, and needless to say, the system wouldn't operate anymore. They had to ship it back to the manufacturer to be low-level formatted again.

Desktop QNX

[fm6]

THIS IS NOT A DESKTOP OS.

Actually, that's not true. QNX has always had a lot of desktop features, and was originally sold to that market.

At one time QNX's realtime features worked in favor of its use on the desktop. That was 20 years ago, when processors were wimpy, and attempts to create GUIs based on DOS had pathetic results.

Of course, QNX's window of opportunity to compete with NT, or even Linux, has long since closed, So the development efforts and the marketing noise emphasize embedded and realtime apps. That's why the Photon GUI is so dated, and the interactive apps are starting to clash with the desktop apps. These are things that could be fixed, but never will be. The reasons are economic, not technical

I'm in love with RtP

[MSBob]

I played with RtP for quite a while. I love it. I learned so much about OS design just by reading the RtP manuals and I think it has a hell of a potential especially on internet appliances and web tablets etc.

The beauty of QNX and RtP is the microkernel design (let the flamewars begin). The OS is exteremly resilient because the core kernel just acts as a messaging bus for all other services that run in the user space. For example, should your filesystem crash you can just restart it like any other user space process!. Alternatively if you don't need multitasking capabilities but memory and hardware are at premium you simply don't run proc and don't have to put up with the overhead of a process scheduler. QNX is such a clean design it puts other microkernels to shame. Rock on QSSL.

Re:I'm in love with RtP

[Anonymous Coward]

Ok, so by your own admission, much of what you know about operating systems you learned from ONE OS's MANUAL.

Perhaps your opinions are less than informed.

I-Opener

[nuxx]

Rmember the I-Opener that everyone was so happy about sucking up and hacking to run Windows/Linux/NetBSD/whatever? The original I-Opener is pretty much exactly what you're describing. It booted up, allowed a connection to the internet, and that's about it. Too bad it died, but then again, most people don't want internet appliances. They want an all-in-one PC.

-Steve

License Fee

[Alsee]

Could you imagine the uproar if Microsoft tried to charge a license fee before you could release an application that ran on the operating system?

-

Re:License Fee

[Anonymous Coward]

Imagine the uproar if all linux applications where commercial.
You forgot the very crucial fact, COMMERCIAL applications.. and, the license fee , for example, a 'small' program , is very low, to help the community, imagine it as the fee you pay to buy windows for. or more specific, the windows development tools.

Re:License Fee

[Anonymous Coward]

can you imagine downloading Windows XP and Visual Studio free of charge from Micro$oft?

You can write your own software, u just need a license if you want to sell your product!

Re:License Fee

[Arandir]

The reason is simple: the "free" version of QNX is an *evaluation* version. Shareware in other words. In order to release a QNX application you must have the licensed version of QNX.

This is in many ways the same situation that exists under Microsoft. If you release a Windows app created on a pirated copy of Windows, and Microsoft found out, you're in deep doodoo. QNX at least gives you an uncrippled evaluation copy to use.

According to my QNX rep, you *can* release non-commercial software for QNX using the evaluation copy. Of course, he's not a lawyer, but a salesman, but I suspect he knows more about it than I.

Re:License Fee

[TheSunborn]

But they do. How would you develop for windows widtout buying windows and thus paing Microsoft. The question is only when do you pay: When you get the os(Microsoft) or when you release the software(QNX)
I know what I prefer :}

Re:License Fee

[renoX]

An interesting reply, but now the question is:
I know how much costs a Microsoft license but how much does it cost to release a commercial software on QNX?

I fear that it must be much more expensive than a Microsoft license :-(
OTOH a company needs many Microsoft licenses to be able to work..

Re:License Fee

[Animats]

Yes. Try releasing an XBox game.

Cluephone ringing... Pick it up!

[Anonymous Coward]

*sigh*

You're absolutely fixated on the eye-candy, aren't you? The point is that QNX is NOT ABOUT THE GUI *OR* THE DESKTOP ENVIRONMENT!

It's like asking what sort of graphics card is on the database server. Interesting, maybe, but the whole point is NOT about the graphics.

They are in NO WAY interested with QNX in taking over the desktop market! The GUI is ONLY there to aid EMBEDDED APP DEVELOPMENT! Nothing more! QNX RtP is NOT aimed at being a full-featured desktop Personal Computer replacement, ala Linux. The only thing the GUI would be good for is an Internet Appliance environment where most of the interaction is through a graphical engine.

But guess what! Most of the time QNX is used, you don't see much in the way of graphics, and even less of any sort of a windowed environment. See that gas pump running QNX? Yeah, it's got a pretty graphics display showing a car going through a car wash, but you *certainly* don't cut and paste anything.

And QNX would *only* love for you to use QNX as your desktop because you would hopefully be developing an embedded app.

Re:Cluephone ringing... Pick it up!

[Anonymous Coward]

Sure, but is that for technical reasons or market reasons? Maybe, unlike Be, they are smart and just figure that there is no room for another general purpose desktop OS. The developer-only GUI certainly looks as or more functional than what shipped with Win95, for example.

aol

[Anonymous Coward]

i'm sure aol will be interested in another os! perhaps another software company to stick in its cheeks for a cold winter... ;)

This reviewer is...

[Anonymous Coward]

...certainly far LESS qualified than what you seem to allow for.

She fixates on the eye-candy on an *EMBEDDED* OS! And complains about desktop performance, when QNX RtP is all about embedded performance, and should have been judged in that light exclusively.

It's like bitching about how my shifter kart won't do very well on the freeway. DUH it performs poorly! I need no review to tell me THAT. But in it's intended environment, small paved tracks, then a review would be helpful in informing me as to how well the OS designers met their target.

Maybe you should pick it up

[ergo98]

Do you recall when Amiga was in talks with QNX to see about basing the new Amiga PC on QNX? Funny thing, but QNX was a very willing participant in those talks. QNX has also coupled with quite a few vendors making full-featured IAs (IAs are just "non-Microsoft desktop PCs": There's nothing super duper special about them), and quite a few are based on it. QNX is _VERY_MUCH_ about "eye candy" because that's one important facet of computing.

Would this help for my 486 lab?

[Beowulf_Boy]

I am the Co-director of my schools Technology Department. We have a whole lab of 486 33's with like 16 megs of Ram a piece. Windows 95 just sucks ass on them. And win 3.1 is not an option (We don't have the liceneses, and we don't have the money to spend on them).
Would QNX be a viable option?
All we need them for is to Internet surf and write essays, and be able to print to a Postscript Network Printer.
Is this possible with QNX?
Are the computers fast enough to run it? Is there enough Hardware support for them (I believe they all are either 486 ps/2s or Compaqs, and they all have 3com cards in them.)
Thankyou

Re:Would this help for my 486 lab?

[Kris Warkentin]

I think you might find RTP would run reasonably well but don't take my word for it. Go to http://qnx.tucows.com/preview/201252.html to download an iso for burning to a CD. If you insert this into the cd drive on an windows box, it will let you make a boot floppy for boxes that won't boot to the CD. Good luck. BTW, you may want to turn of some of the eye candy on the gui (the pointer cam sucks back a few cycles that you can't spare) but I think it might not be too bad.

Maybe we should BOTH pick it up.

[Anonymous Coward]

Ok, ok. Far to used to clueless sheeple than informed people that I don't see eye-to-eye with, and given the utter cluelessness that the Slashdot crowd exhibits with PC hardware, I overreached *some*.

*ahem*

Still, the main thrust of QNX right NOW is not eye-candy or a windowed desktop environment, or the performance on the desktop, but how well it delivers what it promises in its intended arena, the embedded world.

The gas pump doesn't need a windowed environment, nor does a life support system. I'd like to have seen a review that judged QNX RtP in THAT light, not what it does for my PC. As it is, from the review I am no more informed at how well QNX (of today, not the Amiga QNX of the past) does in the embedded environment than I was before I read it.

Re:Maybe we should BOTH pick it up.

[ergo98]

Agreed, and the beauty of QNX Neutrino is that the core of it is so incredibly, beautifully tiny, and having a GUI is completely optional (and the stability of the system is not compromised by a GUI, etc). Having said that technically there is nothing constraining QNX from being a full fledged OS, apart from perhaps the overhead of being "real-time" (though with modern PCs that isn't a big deal and is worth it) and the stability overhead, except for a lack of apps, and that is something that QNX has been working on through 3rd party partnerships: i.e. Opera, etc. With more of that I can see it being a real winner operating system for fat-thin-clients (:-)) that eventually do all that Aunt Martha wants in her day to day living. Hell I'd say it is at that state right now if Aunt Martha uses Hotmail and is a casual computer user.

Should your filesystem crash...

[Blue Lozenge]

Then you're probably SOL. How is it going to load the program that restarts the filesystem?

Re:Should your filesystem crash...

[Anonymous Coward]

The file system drivers are usually in the boot image for the OS, and as such exist in memory. To extend your point... if the filesystem drivers are on the disk, how to you access the disk to start them in the first place?

Re:Should your filesystem crash...

[Anonymous Coward]

RAM.
in your bootimage, all those utils exist (and you can easy add any other tool you want)
Those will always be accessable in /proc/boot
(unless you specify in the bootimage to remove them)
So, if your FS driver die, sure, no problem.
It has happend, and it has been fixed. all without reboot.

UNIX?

[sethadam1]

Why is this UNIX news?

Why not on the desktop?

[jasonv118]

From the screenshots, this thing looks like a suitable OS for the desktop. And it also looks like that's where they're aiming, considering that they have a package installer installing the GNU C++ libs, and all the other little things that people use on the desktop. I'm sick of everything available for x86, so I'm looking forward to QNX becoming ready for the desktop.

Am I off-base here?

Re:Why not on the desktop?

[fredrik70]

Am I off-base here?

yepp, they aiming at *developers* developing embedded stuff.

Re:Why not on the desktop?

[Anonymous Coward]

aiming, sure.
But it still can work damn good :) just that QSSL won't help..

Re:Why not on the desktop?

[fredrik70]

Probably, even if an OS with a round robinkind-of-fashion sheduler might make the forground app feel a bit slow. Mind you the little I tried QNX I never noticed any lagginess. GO for it and try, I gonna play a bit with it for a laugh(just burnt myself a copy;-)

AAAAAAARGH!!!

[Anonymous Coward]

People like you piss me off.

--quote--
I haven't seen this OS before
--unquote--
YES YOU HAVE!!! Ever been to a gas pump? Used a VCR? Played with an I-Opener?

--quote--
but I wasn't surprised to see it had a primarily Windows 9x-style GUI
--unquote--
Stupid, stupid people... It's been posted 100x before, but repeat after me: QNX is NOT a desktop OS. QNX *is* an embedded OS. QNX is NOT a desktop OS. QNX *is* an embedded OS. QNX is NOT a desktop OS. QNX *is* an embedded OS.... So OF COURSE it will look familiar. Maybe it's to SPEED DEVLOPMENT, rather than making new QNX developers re-learn the wheel every time they want to write an embedded app!

Re:AAAAAAARGH!!!

[SilentChris]

"Played with an I-Opener?"

No.

Can someone get this person a CLUE?!?

[Anonymous Coward]

Because it's UNIX-*like*??

Because it implements the POSIX spec?

Gah, WTF didn't you look into it before spouting off?

And..

[mindstrm]

from what I've seen, QNX is one of the more friendly embedded systems.

Ever used VxWorks?

I like QNX and all but...

[Daniel Wood]

it has much of the same problems other non-mainstream operating systems have, application support. Oh, and 3d accellerator support. I first was introduced to QNX through my 3COM Audrey( http://www.audreyhacking.com ), I then installed it as the primary OS on one of my older machines.

I was impressed with QNX, stable, fast, easy to setup(auto-detection on all hardware, unlike some operating systems I know...), quake3 ran :D, etc. However, what finally killed QNX for me was the sheer lack of decent applications. Sure it had phirc, abiword, phplay, etc, but those are no substitute for mirc, MS Word, winamp, etc. In the end I ended up dumping QNX, it is ment for embedded systems(Audrey) where it does well, but it simply is not a good desktop OS.

QNX as a server ?

[Anonymous Coward]

I'm no developer, but I would imagine that QNX would make a great server OS. Particularily a webserver. Has anybody tried this, and been impressed with the results ?

Re:Would this help for my 486 lab? NOPE! Sorry =(

[Anonymous Coward]

"486 33's with like 16 megs of Ram a piece"

Pentium 133 with 32 megs were crawling
in Photon for QNX6!!!

While QNX4 runs perfectly fast on 486 and Pentium,
QNX RtP new GUI crawls do death.
The problem is that all old video card drivers where not ported from QNX4 to QNX6,
which means all the video stuff are emulated, which makes the GUI experience TERRIBLE!

We had a Real-Time lab of QNX4 and the dept.
had to buy brand new Pentium III to make it work,
which wasn't a problem [they had budget].

Also, compiling with Watcom C++ 10.6 on QNX4 is VERY FAST on QNX4, but compiling with g++
[Watcom C++ is not ported and probably will never be, look at Open Watcom status page ]
is extremely slow and requires lots of RAM and a virtual memory file.

Virtual memory on QNX6 doesn't work that well.
Also, QNX RtP 6.1c C++ applications are not backward compatible to QNX RtP 6.1a or earlier,
NO thanks to g++ which bastardized the entire thing forcing stupidities like:

<code>
#include &lt;cstdio&gt;
#include &lt;cstring&gt;
using namespace std;

#define exit( c ) std::exit( c )
#define strlen( s ) std::strlen( s )
#define memset( d,c,l ) std::memset( d,c,l )
#define memcpy( d,s,l ) std::memcpy( d,s,l )
// etc.

Instead of

// Doesn't compile on the new version !
#include &lt;stdio.h&gt;
#include &lt;string.h&gt;
</code>

Notice that this is only C++ code valid,
it works with pure C code.
If you mix C and C++, you're screwed!

Another big problem they decided not to provide
any patch for older version 6.0 and 6.1
and give you only the latest patch
which is full of bugs!

It looks nice, in fact, I don't know anyone who didn't fall in love with the "QNX Graphic designer",
[If only Windows and Linux could have such nice graphics]
but still some fixes are needed... hoping QNX 6.2 will solve the issue!

As far as QNX4 goes, it wasn't Thread-Safe, neither Posix compliant, but the code generated
by Watcom C++ will make you beg for OpenWatcom, about 12x smaller than current g++
maximum optimization code. About everyone in the community agree, but they had no choice.

The kernel gets bigger, the apps gets bigger,
now how the hell does this fit on my 512kB EEPROM chip with an Arcom 486 board?

Okay, buy a new Pentium Arcom board... =P

All this to say, you are out of luck ?
Wanna buy a school license for QNX4 ?
it's very affordable about ~$3,000/computer...
this might tell you why the dept. chosen QNX6 instead of QNX4... =P

New Computers are cheaper then licenses!

QNX6 is not perhaps neither a piece of crapt,
it gots lots of very good thing:
- Posix compliance
- g++ (the old one was good)
- bash/csh/ksh/tcsh
- Nice PhAB
- Extremely cheap RTOS (educational license)
(compared to VxWorks or QNX4)
- Thread-safe conformance
- Very nice HTML documentation
- Very nice Tutorials
- Very nice and responsive community
- inn.qnx.com forums are full of nice people
ready to help you, if needed
[ You never get flame, compared to comp.lang.* ]
- New articles on common problems get posted
every now and then.

I really enjoy the QNX community, cause it stands
and people are always willing to help. Anyway.
It's still a good OS, but with some draw backs,
like any other ones.

Have a nice day!

Some Real-Time QNX6 System Administrator...

argh..

[Suppafly]

Please.. just because a new version of qnx came out, don't post stories about how cool the Icon's were running qnx 2.0 or whatever..

You don't see the ms people reminiscing about windows 3.1 everytime a new version or service pack for windows comes out..

QNX rtp 6 isn't anything like the cli version of qnx that ran on the old icons that the canadian school system is/was so found of.

Instead, you could download qnx rtp and post informative comments discussing its merits compared to other modern day os's or something similiar and actually on topic to the story.

Old apps

[rsd]

"Among those you will find a rootless X Server, GTK+/Gimp/X11Amp ports ..." .

Interesting to note that X11Amp has being dead for some years in favor of XMMS.

Re:AmigaXL

[Anonymous Coward]

Is pretty nice, and it runs under QNX: )

Re:argh..DBD

[Anonymous Coward]

"You don't see the ms people reminiscing about windows 3.1 everytime a new version or service pack for windows comes out"

Of course. Who wants to remember a tragedy?

Boosting the foreground GUI application

[boots@work]

OS/2 also gave a priority boost to the GUI foreground application. (Should I be using past tense? Probably ;-)

Anyhow, it would be an interesting project to try to implement this on Unix. It probably doesn't strictly require the kernel to know about GUIs. It might be enough for the window manager to just advise the kernel to boost a process's priority when it's got focus.

One impediment is that of course making a process less nice is a privileged operation. You might fix this by having a setuid helper, or perhaps by creative use of process capabilities. Arguably user processes *should* be able to make themselves more nice, and then recover, but that would be a more controversial and intrusive change...

Some distributions run X at a negative niceness, to make it more responsive. If we implemented priority inversion then this could work even better: applications would get a boost when X was waiting for them to respond to input or redraw themselves.

Re:Boosting the foreground GUI application

[be-fan]

It wouldn't be too hard on UNIX. It would require that X run as setuid root, but X could manually renice applications on the fly. Actually, the last point you mention would be very helpful for GUI applications. Tannebaum mentions something similar in relation to lottery scheduling in his book "Modern Operating Systems."

Only one mousebutton?

[Anonymous Coward]

Therefore it must be crap.

Re:AmigaXL

[Anonymous Coward]

You really rather want Amithlon, from the same 'AmigaOS XL' package Amiga XL resides in (which is basically a UAE style emulation on top of QNX).

Amithlon runs next to a 2.4.x Linux kernel on x86, i.e. uses Linux mainly for drivers, memory is directly controlled by AmigaOS and it runs circles around any other type of emulation. On a decent Athlon it's 15-20 times faster than the fastest real Amiga.

PhAB gone? HA

[Anonymous Coward]

For all the glowing review she gave the package manager, you'd think she might have ran it. The chances of QNX no longer including PhAB are absolutely nonexistant.

Perhaps she should've installed that package mysteriously labelled "Developer Tools for x86"? It's probably even on the CD. RealPlayer and PhAB have been seperate packages since 6.1.

Reading this review, it really seems like she did a perfunctory once-over of a total reinstall, found things to be basically the same as 6.1, and wrote an article about it. Nothing insightful or interesting here, kids, move along.

realtime systems and ADA

[sireenmalik]

For RT systems you donot use recursive-functions, you stay away from heap( as much as you can) and as opposed to the general notion of realtime, RT systems are called RT because they can guarantee scheduling of tasks! While the idea of "fail-safe" applications have pervaded the general prgramming world it has its roots in RT systems. Consider a program throwing an uncaught-exception on a space-craft!!Plus, the idea of parallel programming really takes off in RT systems. One easily finds out the problems with Semaphores, Condition Variables, Monitors and why ADA 's Protected Types and Rendez-Vous are better than others! i think only ADA fits the true spirit of RT systems.
I have reasons to believe that both C ( and C++) and Java are inching toward a richer functionality but still on an apple to apple to comparison ADA puts them to shame.
I am totally surprised why ADA has not become popular as a programming language?