Interesting GPU/CPU Usage

[kestrel79]

Does that 1C splash screen bug still happen where it makes GPU's run really slow clock speed?

I'm running the official version of the game (no beta patch) with an ATi 5850 should I get rid of this screen? Or is this an old issue?

[EZ1]

I've done the low flight thing many times, but I wanted to see how the CPU and GPU usage looked over varying landscapes. What I am seeing looks like the GPU is begin under utilized in some cases for some reason. In other situations like in a typical combat mission over the channel, the GPU stays maxed out as I would expect.

[NedLynch]

I've had the same experience regarding gpu usage, however my gpu usage as measured with afterburner has gone up significantly (from 60-80% to 80-99%) after the beta patch, which I do see as an improvement.

[DrSanchez]

most probably the cities take a lot of cpu power as well as gpu power. Think about all those LOD swaps and all the data that has to be sent to gpu. gpu is not showing 100% usage because it was waiting for the cpu. therefore in that situation the cpu is the bottle neck.

In the countryside there's not a lot of the cpu to do so the gpu is able to run at full tilt.

[EZ1]

But the CPU usage stays relatively low and does not fluctuate regardless of the GPU usage.

[DrSanchez]

that's more than likely windows spreading the threads across all available cores. try it with a game you know is single threaded and you'll see spread 50/50 (if you're running a dual core) even though it spreads the threads it can never go above 100% total for a single thread.

plus as cod is multi threaded (I think) there could be situations where 1 thread is stalled waiting for another thread to release the data it want's to work on. this can stall the cpu also.

[Igo kyu]

Originally Posted by EZ1

But the CPU usage stays relatively low and does not fluctuate regardless of the GPU usage.

I suspect (I would welcome clarification from someone who really knows) that Hyperthreaded CPUs only ever run up to half speed, because there are half the number of cores that Windows thinks there are, and TANSTAAFL.

[Buzpilot]

If you disable hyperthreading in Bios, will it use 4 cores 100%, instead of 8 virtual ones at 50% ?

[Stefem]

Originally Posted by Igo kyu

I suspect (I would welcome clarification from someone who really knows) that Hyperthreaded CPUs only ever run up to half speed, because there are half the number of cores that Windows thinks there are, and TANSTAAFL.

Windows recognize both physical and logical cores as independent unit, in fact prior to Win 7 the OS thread scheduler not even cared if a core was physical or logical.
The Windows task manager shows the average of all CPU cores usage including logical cores but also can show (depend on configuration) a graph for each core, whether it is physical or logical.

[335th_GRAthos]

You also need to look at the utilisation of the VRAM. The moment your VRAM is full, the GPU will start swapping in order to accomodate for the new graphics. This is when your GPU utilisation goes down (and your fps too) because the bottleneck becomes bringing the data in for the GPU to process them.

Test also flying over the same area above London a second time. You will see a much smoother fly-by the second time (provided the data is still in the memory of you GPU).

Over the sea you do not have any objects to load. Both GPUs (if SLI) work 90%
Over an "empty" (not a lot of objects) map neither. Both GPUs (if SLI) work 70-90%
Over the same map full of objects in order to max the available VRAM of your card, you see the problem. Both GPUs (if SLI) work 50-70%

Look at http://forum.1cpublishing.eu/showthread.php?t=23199

As for I/O I was just watching the HD access light which only blinked once or twice a second throughout the flight.

Once or twice per second HDD access is a lot (for me) and shows the amount of data that needs to be loaded.
For me this was solved and I got smoother gameplay by creating a RAMDISK and loading everything there. The new RAMDISK solutions posted in the forum are much more advanced than the ones I knew in the past and made the difference.

~S~