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Noel

Titan GPU enjoying a nap upon arrival into KORD

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I wonder if there will be a time when P3D can take advantage of all of that idle processing power when it's sorely needed. At touchdown frames went to 14 though this screenshot was captured at around 21.  The striking thing to me is that while the sim appears quite CPU limited on the main thread the GPU is cruising along, down clocking itself w/ only 1500Mb or so of available VRAM being used, as well as GPU utilization of only 55%--this 55% is corroborated by the relatively low frequency & GPU temp you see in the sensor output:

GPUtakinganap_zps00923b9d.png

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Doesn't tessellation make the gpu get used more?

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After 2.4 patch I've been noticing this a lot. Where my gtx 570 was getting rocked at 90-100% GPU usage in 2.3 it has now dropped to 60-70... Making me doubt my gtx 970 upgrade decision.

 

I was getting single digits yesterday in a default city... CPU core one was around 75%, GPU at 30%... What's with that?

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P3D reaches a point of CPU saturation, then you see a dropoff of GPU utilization as well.

 

IE : the CPU is tied up with too much autogen, it can't feed the GPU anymore. I've seen that happen many times when you are in a big city near a heavy airport the GPU usage can sometimes really show low, like 12%

 

When I'm talking CPU saturation I'm only referring to the CPU core that the main program thread is running on NOT the CPU usage you see in task manager - you can have a 12 core processor and  it will not matter. The other threads are only for terrain loading and they aren't recieving any terrain to load because the main thread is bogged down.

 

 

As far as your new GPU showing lower usage: it make sense to me because it is chewing through the tasks it is given much faster than your old GPU thus you have lower overall usage because it is finished faster and has more time to idle. (Think of it as a race - the 970 blew the 570 away and is idling at the finish line waiting for him to finish)

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As far as your new GPU showing lower usage: it make sense to me because it is chewing through the tasks it is given much faster than your old GPU thus you have lower overall usage because it is finished faster and has more time to idle. (Think of it as a race - the 970 blew the 570 away and is idling at the finish line waiting for him to finish)

 

Sure, the question though was will there ever be a time when the GPU can be made to take on more work [w/o getting limited by the CPU].   We understand generic statements such as 'more work has been moved to the GPU...' or something along those lines, which begs the question of whether or not there is some more upside potential in the GPU, or not.  It seems to me a lot of SLI depends on this as well.  Right now throwing in SLI in the scenario I posted above would lead me to believe performance might actually go down.  Any way I slice it, I have a lot of processing power sitting there looking for something to do.

 

This makes one think P3D moving to 64 bit is maybe the time to reconsider the revising the entire rendering engine.  Can something more than texture loading be given to the remaining cores?  How about utilizing some of that fast VRAM for something?  Caching?  Quite clearly I don't really understand what's going on in the software engineering department, but the elephant in the box is the potent amount of poorly tapped hardware--and this machine is now a 15 month old machine.  Meanwhile, the main thread struggles along...

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Right now throwing in SLI in the scenario I posted above would lead me to believe performance might actually go down

 

Ive thought that to myselfe with all this talk about SLI. Or be of no use whatsoever until more loads can be placed upon the GPU

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Doesn't tessellation make the gpu get used more?

 

It's on Ultra and most other scenery & lighting settings are maxed too.

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Sure, the question though was will there ever be a time when the GPU can be made to take on more work [w/o getting limited by the CPU].   We understand generic statements such as 'more work has been moved to the GPU...' or something along those lines, which begs the question of whether or not there is some more upside potential in the GPU, or not.  It seems to me a lot of SLI depends on this as well.  Right now throwing in SLI in the scenario I posted above would lead me to believe performance might actually go down.  Any way I slice it, I have a lot of processing power sitting there looking for something to do.

 

This makes one think P3D moving to 64 bit is maybe the time to reconsider the revising the entire rendering engine.  Can something more than texture loading be given to the remaining cores?  How about utilizing some of that fast VRAM for something?  Caching?  Quite clearly I don't really understand what's going on in the software engineering department, but the elephant in the box is the potent amount of poorly tapped hardware--and this machine is now a 15 month old machine.  Meanwhile, the main thread struggles along...

 

I agree. If they are going to break compatibility with 64 bit then why not rewire the graphics code so stuff like autogen, gauge code and flight model don't cause the main process to bog down - whether it's offloading to GPU or other cores  they need to do something. Several of the higher end addons for P3D and FSX do their own flight model  separate from the sim - the sim is just there to handle rendering/defining the world that you are moving through. But what do I know I'm no software engineer...

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Yes and as Rob A pointed out it's a heck of lot simpler to upgrade your GPU or add another 1, 2 or 3 in SLI.  It seems in the past 5y or more CPU single core performance hasn't really increased enough to matter much w/ P3D/FSX anyway.  So yes, focus on better utilization of the GPU & multicore.   Really kind of pathetic not to be designing the engine for modern hardware, not that LM hasn't done a marvelous job tweaking the old technology.  I guess DirectX 12 has some value too.  Yep--re-write the blithering thing to 2015 standards--then the 3PD community will have something w/ some shelf life to address.  I have to think maybe this will happen--seems pretty obvious if you have the capital and interest, and LM certainly has at least one of those.

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This is why I think DCS with EDGE (2.0) will begin to surpass P3D if they do not get their act together.  At the moment, I realize it is only a combat simulator but from what I understand, it will start to expand as more and more 3rd party devs come online.

 

I already get much better framerates with DCS.  When EDGE drops, it will only get better! 

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Cool I will check that out.   Be fun to play w/ a combat sim too once again.  

 

I understand there are synchronization issues w/ simulators that make them especially challenging to better exploit multicore/multithreading, but still what a huge waste to have those resource as well as the other 28Gb of my quad channel ram at 2400Mhz sitting there on perpetual lunch break.  I guess that's not quite fair as in busy areas texture loading seems to keep them somewhere between 30 and 80% 'busy'.   It will take an outside the box approach apparently to do better at this than we seen in current simulators.  And then yes, SLI. 

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There is A LOT of compatibility code ... LM already dropped ASM support but 3rd party still use it (even new releases) and I'm not sure of how that impacts CPU/GPU usage in P3D.

 

It's going to take time ... not just LM, but 3rd party also.

 

Cheers, Rob.

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