> (1) Is using a "sampling.priority" of 1 merely advisory? It would explain
> everything if those traces are meant to be dropped.
If using the default constructor for APMTracer, then the default behaviour should be to trace all - and setting the sampling.priority to 1 should not override that. Could you try not setting this tag to see if there is any difference?
> (2) Is there any convenient way I can see, with increased logging or
> something, which traces are actually being sent from the client, and which
> are actually received by the server?
You could initially check the traces stored in Elasticsearch using something like: curl http://localhost:9200/apm-hawkular/trace/_search | python -m json.tool