Performance Call Tree Samples breakdown shows zero

(Kazuyuki Arai) #1

Hello! According to the third picture on the Firefox devtools documentation page, the break down of “samples” should show a “samples” value for each row.

When I run Firefox devtools all break down rows shows “0” for the “samples” value - is this an error? Should the break down not show any values for “Samples”? Am I doing something wrong here?


(Harald Kirschner) #2

@Kermit you are right that this looks odd, but has been like that for a while (checked in ESR). I assume that this has been a limitation of the invert algorithm since the panel’s beginnings. Disabling Invert Call Tree in the profiler options shows the samples and self time/cost correctly.

We are working on a new profiler that has a much more advanced Call Tree. You can install it here:


(Julien Wajsberg) #3


It’s totally normal that the self time shows 0 for everything but root nodes in an inverted tree. This is because in an inverted tree, the “children” of the nodes are their parents in the normal tree; basically this is the path that leads to that very sample that’s counted in the root node. That’s why there’s no self time accounted to any of these nodes except the root node.

I’m not so sure for the samples column, maybe we should distinguish the self samples and the total samples, just like we distinguish the total time from the self time.

Anyway you’re likely most interested in the Total time and Total cost when you’re looking at the inverted tree.

Hope this helps :slight_smile:


(Kazuyuki Arai) #4

Great! Thanks for the help! :grinning: :partying_face:
The new profiler works perfectly! :nerd_face: