"Preceding Flows" broken on v57

[embg]

On v48.1-579b1f489, I see "Preceding Flows" for all kernels. On v57.2-687644008, I think because of the two tracks thing, I see two "Preceding Flows" for kernels in the top track and zero on the bottom track. It seems like "Preceding Flows" for the children are misattributed to the parent.

If it's relevant, I am using magic-trace.

v48:

v57, top track:

v57, bottom track:

[LalitMaganti]

Could you please attach a simplified repro JSON demonstrating the problem?

Unfortunately the issue I think here is that the flow might be genuinely ambigious and so it's impossible for us to tell which one to link to (the "top" or "bottom" from your example) it's likely this was only working before because we were dropping overlapping events and with the fix for #4280, this is now appearing.

[embg]

we were dropping overlapping events

Could you elaborate on this? I don't think the old trace was dropping kernels from the trace. What is "dropping events"?

[LalitMaganti]

Ahhh v48 was old enough that maybe you weren't on the version yet where we started doing this.

Please see #4280 (comment) wher I gave a very detailed explanation of exactly what is happening here.

I do need at least a minimal repro to debug this further.