Comparative Analysis of Trace Tools for Real-Time Linux

Real-Time variants of the Linux kernel are in a constant process of development due to the inclusion of new features. In this context, trace tools are necessary to test and validate new implementations. Due to the existence of many parallel Linux projects, there are also several trace tools proposed by different authors. Researchers face many times the difficult task of choosing which trace tool to use in order to validate his/her specific new implementation. This paper analyses three trace tools commonly used for the validation of new real-time Linux implementations: Feather-Trace, Ftrace and LTTng. Motivated by the absence of a set of metrics to evaluate and compare these tools, we also define in this paper a proper set of metrics. We use this new set of metrics to make a comparative analysis among the tools and to present use cases where each tool is the best choice.