What's more important is the actual time it takes to call to the encoder.
Well, what's really important is how much time it takes for the whole frame to render (the time at the top, 100%). If it takes too long to render a frame, then you'll have problems.
How long is too long? Easy: divide 1 second (1000ms) by your frame rate to find out how long each frame should take to render at most. For example, for 30fps, 1 frame is 1/30th of a second, or 0.033 seconds, or 33ms. If you are streaming at 30fps and you see in your log that it takes longer than 33ms to render 1 frame, you'll have problems and need to reduce load somehow (choose a faster preset, lower resolution, slower framerate, etc.). Same deal with 60fps: 1/60th of a second is 16.7ms, so if it talks longer than than to render a frame, you'll have stream performance problems.
Underneath the whole-frame render time, it breaks down what time was spent where. If your frame render time is too high, this can help identify which part of the rendering process is causing the most problems, and could hint at what you need to do to fix it.