QNX RealTime Platform Preview

Mike Bouma writes "Since the QNX RtP will be free for personal use this late-september, this BeNews preview will see how QNX RtP compares to BeOS and to free Linux systems. QSSL is a member of the Phoenix Platform Consortium which goal is to produce an Amiga-like successor OS. QNXStart.com will be a starting point for the QNX RtP community and is first in a series of Phoenix partner websites."

Comments

Free QNX

[Animats]

QNX is a neat little system. I just wish they'd get the promised free version out the door.

A few points to note.

• QNX is not anything like UNIX. There's a POSIX emulator, but underneath, it's a message-passing microkernel. Almost everything runs in protected mode. You call services by passing messages to them, which is done very efficiently. If you're going to program for QNX, learn how to use its interprocess communication services; don't program it like it's a UNIX variant.
• It really is hard real-time. There's a defined maximum interrupt latency. This is a big win for streaming media and video.
• There's no paging. Everything has to fit in memory. This is probably good; memory is cheap enough today that paging is generally a lose. The performance hit when you have to page in from disk on Windows or UNIX is so huge you don't want to page anyway. QNX software tends to be much less bloated than Windows or UNIX, so memory consumption is less anyway. It's possible to do useful web browsing on a 386 machine with QNX, booting from a floppy and not using the hard disk. (QNX gives away a demo disk for this.) It's supposed to work. QNX is used mostly for hard real-time industrial control applications. There are nuclear reactors controlled by QNX. QNX users have a very low tolerance for crashing. The top priority at QNX Inc. is eliminating crashes, not adding features. Don't expect dancing paper clips.

Re:Constant bashing...

[variable]

This is a sticky issue.

For example. If I didn't turn on "enable sound" the last time I built a kernel, can I just rebuild sb.o and insert it into the kernel? Nope.

Yes Linux has loadable modules, but that is not nearly the same thing as what QNX provides with each driver being a process that can be started with an & and killed via "kill" at runtime and with each driver being in its own memory space. Linux is a monolithic kernel (which can sometimes have advatages) and you still need to rebuild stuff to make devices work. This is even more true between kernel versions.

Good that you made this post, everyone should be informed and not too hung up on buzzwords.

Re:the QNX advantage

[GypC]

Pantsless reboots? Oh man... I'm so there!

"Free your mind and your ass will follow"

I Agree With The Article

[Phrogman]

I am one of the folks running the pre-release version of this puppy, and I have to agree with the article completely. I had no problems installing it, and have had no problems running it. It detected my hardware perfectly and installed like a breeze (probably the easiest installation of any software I have ever installed). This is going to be a platform to watch.