MCDRAM as High-Bandwidth Memory (HBM) in Knights Landing Processors: Developer’s Guide

This publication is part of a developer guide focusing on the new features in 2nd generation Intel® Xeon Phi™ processors code-named Knights Landing (KNL). In this document we discuss the on-package high-bandwidth memory (HBM) based on the multi-channel dynamic random access memory (MCDRAM) technology: Three configuration modes of HBM: Flat mode, Cache mode and Hybrid mode Utilization of the HBM as addressable memory using two methods: by setting affinity policy with the numactl tool and through the usage of special allocators in the memkind library Guidelines for determining the optimal usage model for applications running on bootable Knights Landing.  Colfax_KNL_MCDRAM_Guide.pdf (255 KB) See also: colfaxresearch.com/get-ready-for-intel-knights-landing-3-papers/ Table of Contents 1. MCDRAM in KNL 2.1. Cache Mode 2.2. Flat Mode 2.3. Hybrid Mode 3. Using HBM as addressable memory 3.1. numactl 3.2. Memkind Library 3.3. Fortran 4. Choosing Memory and Programming Model 4.1. Programming with HBM… 4.2. …and Programming without HBM Appendix A: Application Memory Footprint Appendix B: Bandwidth-Critical Data 1. MCDRAM in KNL Memory bandwidth in computing systems is one of the common bottlenecks for performance in computational application. Bandwidth-limited applications are characterized by algorithms that have few floating point operations per memory access (low arithmetic intensity). Algorithms in this category … Continue reading MCDRAM as High-Bandwidth Memory (HBM) in Knights Landing Processors: Developer’s Guide