ATI vs nVidia, REAL TIME
So, generally speaking, the vast majority of Linux users seem to prefer nVidia over ATI. But what about when running a real time kernel? I have read, though I dont know how up to date the information is, that ATI is better in this regard. Im curious to know if this is still true.
I got the information from LinuxCNC.org - Home
Well, appareently the site was last updated about a year and a half ago... Honestly, I don't know which would be better in a "real-time" system, and frankly, as an engineer with 30 years experience in real real-time systems, I don't think there is ANY linux distribution which meets a true hard real-time requirement. An OS designed as a truly deterministic real-time system, such as QNX, will be true real-time with either nVidia or ATI hardware unless they advise otherwise.
Well, I got into the whole real time thing when I started wanting to get into CNC. EMC2 seems like the (free) program to use for CNC on the computer, which happens to be for Linux.
When I started reading the FAQ on the LinuxCNC page, it mentioned how ATI was better in a real time environment (at least for this specific application), which I found interesting, and was wondering if the information was still true today.
Well, that's a good question. For real-time, it isn't a matter of latency (perceived speed) as much as determinism, which is to say consistency in performance. Ie, do the same operations always take the same amount of time (within knowable bounds)? If so, then it is suitable for real-time systems. If not, then it isn't. As my signature says, "Sometimes, real fast is almost as good as real time."... :-)