Always-on instrumentation for application introspection in HPC
Amir Raoofy, Josef Weidendorfer, Michael Ott · 2022
Obtaining insights into the dynamic behavior of user code is crucial for supercomputing centers to support both better operation and co-design of future systems. To this end, always-on instrumentation is the key: enabling all running code to dynamically forward metadata such as compute phase changes to the system would provide important information for those goals. To keep the overhead low, the system must be able to deactivate instrumentation points with high trigger frequency on demand. In this poster, we present a simple always-on instrumentation method for C/C++ which can be easily used by developers, copying a single source file into their code base. Our evaluations show that the overhead in the deactivated state is low enough for the manual instrumentation to stay compiled in, all the time.