mojoseeker Posted May 17, 2012 Report Share Posted May 17, 2012 I have a line of data in my upper leftscreen area. It shows F-act, F-sim and Frame. The data under the three shows 15.0, 19.90 and 0.067.What do the numbers mean and which should I be concern with (frame rate)? Thanks Quote Link to comment Share on other sites More sharing options...
chris k Posted May 17, 2012 Report Share Posted May 17, 2012 First one is the actual frame rate you want to read (f-act) - it's the FPS being achieved on your video card.Second one (f-sim) is the math internally that X-Plane is trying to use for it's physics calculations. It should never drop below 19 or so, else things become unpredictable. If your f-act is below the f-sim value, then it's running in slow-motion since the video card cant keep up.The third value "frame time" is the elapsed time in milliseconds between finishing the calculations and pushing info to the video card, and the return from the video card. (I believe - someone correct me if Im wrong here..) i.e. how long it's taking OpenGL to render the frame... as this is outside X-Plane's control once it instructs the card what to do. For example, if my video card (f-act) is doing 50 FPS = 1000ms / 50 frames = 0.020 sec per frame, which is about what I see on my system.- CK. Quote Link to comment Share on other sites More sharing options...
s839sd82k Posted June 12, 2012 Report Share Posted June 12, 2012 How do you show frame rate? Quote Link to comment Share on other sites More sharing options...
PhM Posted June 25, 2012 Report Share Posted June 25, 2012 ... If your f-act is below the f-sim value, then it's running in slow-motion since the video card cant keep up....In fact the rendering frame time depends on many parts of a system, to make it simple if you get slo-mo then :- If your GPU usage is at, or close to, 100% you are GPU bound, it can't keep up with what has to be done.- If your CPUs usage is at, or close to, 100% you are CPU bound they can't keep up with what has to be done.- If none of the above applies then your are API (openGL) or I/O (PCIe) bound.PhM Quote Link to comment Share on other sites More sharing options...
MdMax Posted June 25, 2012 Report Share Posted June 25, 2012 How do you show frame rate?In Data Input & Output, then select frame rate:http://wiki.x-plane.com/Chapter_5:_X-Plane_Menus#The_Settings_Menu Quote Link to comment Share on other sites More sharing options...
FloB Posted July 31, 2012 Report Share Posted July 31, 2012 (edited) In fact the rendering frame time depends on many parts of a system, to make it simple if you get slo-mo then :- If your GPU usage is at, or close to, 100% you are GPU bound, it can't keep up with what has to be done.- If your CPUs usage is at, or close to, 100% you are CPU bound they can't keep up with what has to be done.- If none of the above applies then your are API (openGL) or I/O (PCIe) bound.PhMCan you explain what API-bound means?In fact neither my CPU (i7 2600k@4.2) nor my GPU (GTX670@stock, 2GB) is close to beeing maxed out.CPU-load is typically 75% at one core, others are used to around 40% (windows task manager, performance monitor).GPU-load is around 70%. NVIDIA Inspector shows that the "bus-usage" is almost zero (but maybe this is not the PCIe bus?).Framerates are good and about what I expected - but it's weird nonetheless. Only way to max out the GPU is running HDR+SSAA.Just curious how that makes sense...ThanksFloPS: XPlane's FPS counter always shows a CPU usage of 0.998 or so. Edited July 31, 2012 by FloB Quote Link to comment Share on other sites More sharing options...
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