[revelation]

They call it a flame graph and what you are seeing are call stacks. X axis is time, Y axis is call stack depth.

The very bottom layer is the function you are analyzing, ever layer above is a function called by the one directly below it.

[jberryman]

> X axis is time

That's not correct from what I'm reading.

[revelation]

If you are sampling the stack at equidistant points in time (or, sampling theorem and all, fast enough) and then determine the width on the basis of "seen in fraction of samples", that's pretty close to time. (timespan if you want)

[michael_h]

The span on the x-axis is the amount of time spent in a function, but not the passage of time left-to-right.

[michael_h]

I down voted you because I'm on a phone and my thumb is a bit bigger than the voting triangles - apologies.

[vive-la-liberte]

Thank you. Very succinct explanation. I like that.