Sometimes while using my computer I notice random slowness when launching a certain application or some feature that just doesn’t run very well. That’s always reason enough for me to take a deeper look.
My tool of choice for analyzing performance issues is Hotspot, KDAB’s excellent perf visualizer. It comes with an easy to use GUI for browsing the results collected by it. Particularly its flame graph lets you quickly detect, well, hotspots during execution. Just launch an application through Hotspot or attach it to a running one and look at the graphs. Depending on your system configuration you might need to adjust the perf_event_paranoid kernel setting in order for it to inspect other processes.
