I am reading through some of the Hawkular APM code and have been looking at how trace fragments get created and written on the client side. One of the classes I am reviewing is FragmentBuilder.java. Its javadocs state that the sequence of events within a thread of execution should be in sequence. It made me wonder whether it is possible to trace async operations. I found https://issues.jboss.org/browse/HWKAPM-77 which apparently improves support for async execution.

Gary, can you or anyone else familiar how things work, give a brief explanation of how things work async flows? Most everything in hawkular-metrics is async and reactive. That makes debugging difficult at times where you have to rely primarily on logging. I am wondering if Hawkular APM would be a good tool for these types of situations.

- John