Although my master thesis was in local tracing, e.g. Lttng and dtrace, there are very powerful tools called end-to-end tracers that basically work tracing a request from top to bottom in distributed systems. In other words, it allows to log information of distributed system.
The example in  is the wikipedia, but any major platform nowadays is distributed in several places and could potentially use this tool.
An example of end-to-end tracer is X-trace, which was developed by Rodrigo Fonseca, and presented at his PhD Thesis and it’s available in his github account .
Currently there are several tools, in this so called end-to-end tracers but also techniques and tools to complement this, e.g. Pivot tracing technique.
This is clearly a hot-topic and has received for attention from several companies, e.g. Google and others.
I will be posting more about end-to-end tracers soon.