Native Memory Tracking (NMT) has supported diagnosing memory issues in Hotspot for over a decade. Yet, much of the native memory allocated cannot be accounted for using NMT, as it is not only Hotspot but core libraries, JNI and FFM which may perform native allocations. Clearly, NMT must extend itself if it intends to remain a useful tool.

In this talk, I will present a design for extending NMT to core libraries and a possible future extension to FFM. External APIs will be shown in the context of porting small portions of the core libraries. Internal design details, including data structure design, will likewise be presented and its trade offs discussed. Finally, possible ways of bringing NMT and the new Foreign Function & Memory API will be presented.