Feature or enhancement

Proposal:

Falls under #142927

When running profiling to identify bottlenecks, I rarely care about global percentage of runtime. For example, the profiling results in matplotlib/matplotlib#31059 show that ~40% of test script runtime is dedicated to imports and module initialization, but I only care about the post-init functions. For that it's more useful to be able to drill down to different top level functions, and measure child percentages relative to that.

So, I would proposed renaming "Percentage" in the tachyon flamegraph tooltips to "Percentage of Root", and add a "Percentage of Selected" when the user has clicked in to a specific function.

UI mockup for Flamegraph and Inverted Flamegraph, using the demo from here: https://docs.python.org/3.15/_static/tachyon-example-flamegraph.html:

When at the root, the extra field can be dropped:

Has this already been discussed elsewhere?

This is a minor feature, which does not need previous discussion elsewhere

Links to previous discussion of this feature:

No response

Linked PRs

• gh-150258: Show relative percentage on Tachyon flamegraph #150266
• [3.15] gh-150258: Show relative percentage on Tachyon flamegraph (GH-150266) #150312