The group develops, validates and maintains simple open source tools, which support performance analysis, the creation of performance models and the performance engineering process on the compute node level.
The well-known tool collection LIKWID (http://tiny.cc/LIKWID) comprises various tools for the controlled execution of applications on modern compute nodes with complex topologies and adaptive runtime parameters. By measuring suitable hardware metrics LIKWID enables a detailed analysis of the hardware usage of application programs and is thus pivotal for the validation of performance models and identification of performance patterns. The support for derived metrics such as attained main memory bandwidth requires a continuous adaptation and validation of this tool to new computer architectures.
The automatic generation of Roofline and ECM models for simple kernels is the purpose of the Kerncraft Tool (http://tiny.cc/kerncraft). An important component of Kerncraft is the OSACA tool (Open Source Architecture Code Analyzer), which is responsible for the single core analysis and runtime prediction of an existing assembly code (http://tiny.cc/OSACA). For all the tools mentioned above, we aim to support as many relevant hardware architectures as possible (Intel/AMD x86, ARM-based processors, IBM Power, NVIDIA GPU).
Based on LIKWID and the existing experience in performance analysis, the group is also pushing forward work on job-specific performance monitoring. The goal is to develop web-based administrative tools such as ClusterCockpit (http://tiny.cc/ClusterCockpit), which will make it much easier for users and administrators to identify bottlenecks in cluster jobs. ClusterCockpit is currently being tested at RRZE and other centers.