This is from the settrace_methods_duration_threshold documentation:
Such methods will be traced and reported if one of the following applies:
- This method’s duration crossed the configured threshold.
- This method ended with Exception.
- A method executed as part of the execution of this method crossed the threshold or ended with Exception.
- A "forcibly-traced method" (e.g. DB queries, HTTP exits, custom) was executed during the execution of this method.
Due to the way the agent works, we must keep complete traces, so we must send all methods leading to a method we want to keep. We can discard only spans on branches that do not directly lead to forcibly traced spans.
The way to reduce this and make sure it makes more sense it to be more specific with the trace_methods configuration. This configuration was introduced in order to trace specific methods. In order to get what you want, you will need to spend some time on it and be very specific in what you want to get spans for.