Open Source Summit North America 2023

Due to the high price and limited capacity of DRAM, data access pattern aware system operation is important for efficiency and performance of memory intensive systems. Absence of efficient and accurate data access monitoring techniques can be one of the challenges for that. DAMON is a Linux kernel subsystem that provides a framework for such accurate, light-weight and scalable data access monitoring, and the monitoring results based access-aware system optimizations. For easier development of such optimizations, DAMON provides a feature called DAMon-based Operation Schemes (DAMOS). Using the feature, DAMON users in both kernel and user spaces can do access-aware system operations with no code but simple configurations. Both DAMON and DAMOS are in the mainline Linux kernel today. A user space tool called Data Access Monitoring Operator (DAMO), which makes the work much easier is also available. This talk will introduce the internal architecture and design of DAMON, DAMOS, and DAMO followed by a demonstration. The demonstration will show how easily people can monitor access pattern of the system, and what optimizations they can make using DAMO. Further, it will demonstrate how you can write your own DAMON user space tools, using the core module of DAMO.