Some recent posts in this thread have started to drift off topic.

It would be great if we could keep tihis thread focused on Red Rushes Full Debayer performance problems on the new Nehalem Macs.

Thanks.

Quote Originally Posted by Deanan View Post
Yes, we have already full debayer. As I said before you do need to optimize for multiple clips and threads.

Why? Nahalem's architecture is deffierent than the old architecture in that it's a slower processor but it has 8 real (but slower) cores and 8 hyperthreaded cores. This means that given different compute problems it will perform differently than the old cores on a per thread basis. That's why you have test for overall speeds by maximizing more clips in parallel with an appropriate amount of threads per clip. There are other factors like more memory bandwidth and turbo modes that affect speeds.
OK, we are rather busy here so I have only now had a chance to rerun some tests. I tested a batch of 3K clips, all with the same RSX adjustments - +0.2 on exposure, +2 on brightness, no other manipulations.

So - good news is that setting red rushes up to render multiple clips does indeed improve performance on the 8core Nehalem quite a bit when doing a full Debayer render. 6clips at once and "auto" on cores per clip seemed to be the best recipie. With those new settings I could improve the 8core Nehalem from 5m12s/100frames (at 1 clip an once) to 1m32s/100frames.

The bad news is that at 1m32s/100frames the new 8core Nehalem is only about 20% faster than the 2 year old 4core (1m54s/100frames).

I'd say the problem is still there... And, while it helped, the main issue must lie somewhere else than in clips-at-once/cores-pre-clip -settings...

Help!?!


Quote Originally Posted by Deanan View Post

B) A stock nahalem from apple with the fastest processor and memory. Nothing else is modified.
That wasn't very helpful.

Anyone else out there that is getting great FULL DEBAYER WITH RSX performance out of red rushes on an 8core Nehalem that would like to contribute the usual HW/SW specs (RAM, RR version, QT version, Mac OSX version etc etc.)


Quote Originally Posted by Deanan View Post

If the top swedish mac retailer couldn't get the RAM setup right, did they use the right type/speed memory and what else did they get wrong?
I have a real problem here and i'd appreciate if you kept the sarcasm down.

The RAM was delivered after the computer got here and I stuck it into the free slots (slots no. 4). On boot-up a "RAM utility" asked me to re-allocate the bigger modules to the no. 2 slots - hardly intuitive, and I'm sure better people than me have done the same "misstake" on the new Nehalems.


Really, this is a huge and real problem and I'm trying to figure it out and share with others here on the forum.

Still scratching my head.

Jack