Usually my content is created at 30fps, and I output at 60fps. This works great for the performance meter because I can gauge when I am pushing the machines to hard and am getting close to the 30fps. However, when you output at 30fps, and your content is 30fps there is way of telling if you are getting close to that 30fps. I wish there was a way to see above what I am outputting, maybe what the potential fps is.
I think i understand where you are coming from, though it is not quite as simple as it sounds.
First of all, for the most smooth output you want the engine to be running as close to 60FPS as possible. With inter-frame blending, even with 30FPS content we are rendering a unique frame with each render pass; half of them would be interpolated from the adjacent frames. (You can turn this off, its a pin in the media player if you want to see the difference). So i would always suggest striving for the highest framerate possible. If the framerate of the engine drops below the media frame rate then the player will start to drop frames which can quickly become noticeable.
In terms of knowing the 'potential frame-rate' that is very difficult. The frame rate is limited by any number of performance bottlenecks such as: Video Memory availability, System Memory bandwidth, Drive Access bandwidth, Drive latency, or GPU Texture bandwidth to list a few. Many of these can not be known until you measure them. The latency of the media drive has a huge effect on playback for example, and is itself dependant on many factors ranging from Windows pre-fetching to the drive's age and utilisation and can even be file dependant. This means that we dont really know what the system can do without actually trying it.
That being said, we do want to extend the performance meter to include other measures such as CPU utilisation and system temp. These will at least give you an indication of how much overhead is left in key areas of the system.
Hi Ryan. 'Potential frame-rate' might not have been the best solution, it is what I could think of at the time. However, I feel like you get where I am coming from. The reason I am running at 30fps is because I am using a 4k output to a Datapath X4 to get four 1920x1080. I can only run 30hz into the datapath at 4k, otherwise I would always run at 60.