Jun 26, 2002

QNX Performance Problems

After my third and final attempt with QNX, I felt I had to write in hopes of finding others who have had similar experiences. Hopefully someone can tell me what's wrong here. QNX has left me with a very sour taste in my mouth.

The first system I tried to install QNX on was an old 100MHz Pentium with 32 megs of RAM. This was back in the Fall of 2000. Now, since QNX was supposed to be "tiny" and run on things like watches and hospital equipment, I was expecting it to breathe new life into my old Pentium. WRONG. The hard drive practically ate itself to death every time I launched a new app, and the RAM was almost always at full use. I mean what the Hell. But I gave it another try when Patch A came out. And Patch B, which killed networking entirely. I had given up and didn't want to touch Patch C when 6.1 came out.

QNX 6.1 was a lot nicer than 6.0, but it was still a resource hog. RAM allocation was no better and processor usage was actually up. I decided I might as well upgrade the system with a new motherboard and a 500MHz Pentium II, but to my chagrin the five-fold increase in speed (not to mention MMX!) did little to boost the sagging performance. Willing to do anything to clear up this performance black hole, I installed Patch A to 6.1 the minute it was available. I noticed a slight increase in screen redraws but nothing more.

To this day, even with the new 6.2 on a 2GHz Pentium 4, the QNX performance mystery boggles my mind. Either QNX doesn't really meet the defintion of a "real-time" OS, or we need to consider changing what "real-time" means. I wouldn't want my insulin drip running QNX in the middle of a surgery. I might die while it's paging in from /swap, and that's just unacceptable.

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