Open Source Summit + ELC Europe 2018

Finding and analyzing performance issues on embedded devices can be a tiresome search. Nowadays, modern sampling and tracing technologies are built into the Linux kernel to address this, in the form of perf and LTTng respectively. Still, the vast amounts of data recorded are difficult to handle on the limited embedded devices themselves. In the talk, I present Hotspot, an open-source performance analysis tool based on perf that enables you to visualize the recorded information and lets you navigate through the enormous amounts of sampled data offline. For tracing, sophisticated analysis tools such as TraceCompass already exist, but trace points in embedded userspace applications are rare. We see how LTTng tracepoints can be added to userland UI frameworks on the example of Qt. Here, I explain LTTng's low overhead and outline our plans in instrumenting Qt for the LTTng tracing ecosystem.