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QNX is now free for anything non-commercial, plus there's an RPi image

blackberry.qnx.com

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Re: QNX is now free for anything non-commercial, plus there's an RPi image

#311

Post by CoastalCoder »

ChrisC-POV wrote: post #213
vbezhenar wrote: post #200

Earlier quoted context omitted.

Who needs throughput? Server software, but Linux is already dominant there and everyone's happy. For everything else, including desktop and mobile operating systems realtime sounds like a good idea.

That's waaaay too broad a grouping. You're thinking of PC's, basically, in one form or another (or their modern replacement, mobile devices). Industrial automation and hard real-time embedded devices like those that control surfaces in Fly-By-Wire systems are out there and with those it's not a matter of "throughput" but a matter of timeliness. I did a major project with QNX about a decade ago where the maximum allow…

What a terrifying and cool project!

Can you say what kind of shop / machine it was for?

Re: QNX is now free for anything non-commercial, plus there's an RPi image

#312

Post by DeathArrow »

workfromspace wrote: post #284
vundercind wrote: post #96

QNX and BeOS were the only operating systems I tried in the early '00s that could make old single-core mid-90s Pentiums feel excellent and snappy to use. Far, far better than any Windows version, or Linux. I assume it's mostly scheduler stuff and much better multimedia stacks, in both cases. I always hoped the operating systems of the future would feel more like that. Closest we've got is probably iOS and it cheats b…

As someone also have used BeOS and OS/2 Warp, I miss the snappiness of old systems. (I never got my hands on QNX) What OS nowadays is the closest to that snappiness? Haiku OS? (I'm a happy M1 Macbook user, but it sometimes feel note nough.)

>What OS nowadays is the closest to that snappiness? Haiku OS?

Probably Haiku running native Haiku apps.

Re: QNX is now free for anything non-commercial, plus there's an RPi image

#313

Post by cesarb »

RandomThoughts3 wrote: post #301
vbezhenar wrote: post #200

Earlier quoted context omitted.

Who needs throughput? Server software, but Linux is already dominant there and everyone's happy. For everything else, including desktop and mobile operating systems realtime sounds like a good idea.

> Who needs throughput? Server software, but Linux is already dominant there and everyone's happy. For everything else, including desktop and mobile operating systems realtime sounds like a good idea. No, not at all. The actual question is who needs realtime. Desktop is a typical place where you absolutely don't need realtime. You just want latency to be under the user perception threshold but that's easily achievabl…

> Desktop is a typical place where you absolutely don't need realtime.

On a desktop, you want at least soft real-time when playing any sort of multimedia (audio, video, or interactive applications like video games). Otherwise, you get things like glitched audio or dropped frames.

Re: QNX is now free for anything non-commercial, plus there's an RPi image

#314

Post by chronogram »

vbezhenar wrote: post #200
scheme271 wrote: post #173

Earlier quoted context omitted.

"Real time" is only good if you need guaranteed responsiveness within certain time limits. It can actually be suboptimal and slow you down if you don't need it and want to optimize other things like throughput.

Who needs throughput? Server software, but Linux is already dominant there and everyone's happy. For everything else, including desktop and mobile operating systems realtime sounds like a good idea.

Desktop use at its lowest latency is typically 17ms and up to 33ms when using a 60Hz screen with one frame in the buffer and whether you have to wait for the one after that. But most operating systems and games default to more than one buffered frame. Still, even that lowest case scenario is a pretty big budget of time. The microsecond precision of a RTOS is not necessary then. If you want to increase responsiveness or reduce latency for interactive use of desktops or phones there are different avenues to approach to shave off milliseconds at a time.

Re: QNX is now free for anything non-commercial, plus there's an RPi image

#315

Post by CoastalCoder »

sov wrote: post #186
gosub100 wrote: post #123

Earlier quoted context omitted.

You would use it if you wanted to get a job doing RTOS dev and wanted to show you had some skin in the game.

any commercial rtos shop where QNX may be appropriate is either using 1. some wacky expensive proprietary rtos that you've never heard of, 2. freertos or 3. real-time linux depending on what they need. asking what makes QNX a compelling rtos when freertos exists, is widely supported and used, and has an MIT license is a very valid question. further, no one in embedded actually cares what RTOS you used. they are all s…

> no one in embedded actually cares what RTOS you used. they are all similar enough that you won't get stuck if it's a brand new RTOS

Out of curiosity (as an outsider), how does the availability of device drivers factor in?

I assume they still need to be ported to each combination of OS and device.

Re: QNX is now free for anything non-commercial, plus there's an RPi image

#316

Post by cameron_b »

smarx007 wrote: post #274
znpy wrote: post #268

Earlier quoted context omitted.

> but not Linux. I disagree. Linux merged the real time stuff ( https://news.ycombinator.com/item?id=41594862 ) not so long ago so it's now a real-time capable kernel, and hence it should be held comparable to other real time kernels.

Good luck certifying an automotive or an industrial system that can lead to loss of life or severe disruption if it malfunctions. As far as I am aware, QNX, VxWorks, and CMSIS have all been used in systems that passed certifications. As IoT &co. get applied more broadly in our society, they are put in more places where they are expected to function flawlessly. I would rather want my power grid or water utility operat…

One interesting morsel in all of what you described is that for all of the hoop-jumping SpaceX does to bolster rt-Linux, it is -still- easier/faster/ better by some business metric for them than the alternative.

If the redundant hardware and some ground rules they have in place have made the onboarding of developers better and faster, than perhaps it should be recognized that they seem to be prioritizing the DX - especially since plenty of applications in RT will also use redundant hardware and confine their hardware selection similarly to prioritize the performance targets of their application, SpaceX just added developers to the feature matrix.

Re: QNX is now free for anything non-commercial, plus there's an RPi image

#317

Post by RandomThoughts3 »

cesarb wrote: post #313
RandomThoughts3 wrote: post #301

Earlier quoted context omitted.

> Who needs throughput? Server software, but Linux is already dominant there and everyone's happy. For everything else, including desktop and mobile operating systems realtime sounds like a good idea. No, not at all. The actual question is who needs realtime. Desktop is a typical place where you absolutely don't need realtime. You just want latency to be under the user perception threshold but that's easily achievabl…

> Desktop is a typical place where you absolutely don't need realtime. On a desktop, you want at least soft real-time when playing any sort of multimedia (audio, video, or interactive applications like video games). Otherwise, you get things like glitched audio or dropped frames.

Yes, I agree especially for audio which is a typical exemple of a latency sensitive application (video games are generally purposefully design to be as latency insensitive as possible and will drop frames with no impact on actual gameplay). But a performent application and proper scheduler priorities will bring you there without a RT kernel.

Re: QNX is now free for anything non-commercial, plus there's an RPi image

#318

Post by ChrisC-POV »

CoastalCoder wrote: post #311
ChrisC-POV wrote: post #213

Earlier quoted context omitted.

That's waaaay too broad a grouping. You're thinking of PC's, basically, in one form or another (or their modern replacement, mobile devices). Industrial automation and hard real-time embedded devices like those that control surfaces in Fly-By-Wire systems are out there and with those it's not a matter of "throughput" but a matter of timeliness. I did a major project with QNX about a decade ago where the maximum allow…

What a terrifying and cool project! Can you say what kind of shop / machine it was for?

It was a hot-strip mill; this video shows the general gist of it: https://www.youtube.com/watch?v=13dUL9OQFvw&t=15s> (tho the ones I worked with were all made by GE).

Re: QNX is now free for anything non-commercial, plus there's an RPi image

#320

Post by pizzafeelsright »

workfromspace wrote: post #284
vundercind wrote: post #96

QNX and BeOS were the only operating systems I tried in the early '00s that could make old single-core mid-90s Pentiums feel excellent and snappy to use. Far, far better than any Windows version, or Linux. I assume it's mostly scheduler stuff and much better multimedia stacks, in both cases. I always hoped the operating systems of the future would feel more like that. Closest we've got is probably iOS and it cheats b…

As someone also have used BeOS and OS/2 Warp, I miss the snappiness of old systems. (I never got my hands on QNX) What OS nowadays is the closest to that snappiness? Haiku OS? (I'm a happy M1 Macbook user, but it sometimes feel note nough.)

I worked with QNX on a floppy and it was the first time, after years of Windows, Mac and DOS in the 90's, that something felt so magical.

Every OS has a delay between mouse click and impact on the UI. Only QNX has ever felt sub 30ms in response time.

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