Function write 

pub fn write<W: Write>(out: &mut W) -> Result<()>

Print profiling scope tree.

Example output:

frame: 100.00%, 10.40ms/call @ 96.17Hz
  physics: 3.04%, 3.16ms/call @ 9.62Hz
    collisions: 33.85%, 1.07ms/call @ 9.62Hz
  render: 96.84%, 10.07ms/call @ 96.17Hz

Percentages represent the amount of time taken relative to the parent node.

Frequencies are computed with respect to the total amount of time spent in root nodes. Thus, if you have multiple root nodes and they do not cover all code that runs in your program, the printed frequencies will be overestimated.