Collaboration Summit 2014

In NUMA systems, each CPU has its own bank of memory, resulting in fast access to local memory, and slower access to memory elsewhere in the system. Recently a mechanism has been implemented in the Linux kernel to automatically run programs near their memory, and to move memory to near the programs using it. This presentation explains why computers are built this way, why NUMA locality matters, how the automatic NUMA balancing kernel code works, what it can do, and what kind of performance improvements have been observed. Also covered are how to monitor the NUMA locality of programs, and how to manually tune the NUMA locality in cases that are not handled by the automatic NUMA balancing code.

This presentation will help give an overview of the current status of Automatic NUMA balancing related changes in the upstream kernel backed by some empirical data to show how the out-of-box performance improves . It shall hopefully also facilitate discussion on opportunities for further optimization/improvements.

The audience is anyone interested in Linux Performance, Scaling of workloads on NUMA platforms