When can we use it?

As an example of this tool's usability for performance work, KDAB mentions debugging high video memory usage by accumulating textures. In its latest versions, GammaRay can show textures relating to single Qt Quick items, allowing you to locate culprits. Another example is the debugging of 100% of the CPU load caused by a constantly firing, zero-millisecond timer, which, erroneously, isn't set to singleShot. A quick glance through the list shown in the Timer's view during runtime reveals the problematic guy in an instant.

Additionally, we can also use the tool's capabilities in the visualization of graphic scenes, state machines, and Qt models to examine complex hierarchies at runtime, which can indirectly benefit our performance work.