POWER9

POWER9
source
Name	POWER9
Designer	IBM
Bits	64-bit
Introduced	2017
Design	RISC
Predecessor	POWER8
Successor	POWER10

POWER9. It is a family of 64-bit multi-core microprocessors designed and sold by IBM, succeeding the POWER8 generation. The architecture was developed through the OpenPOWER Foundation, a consortium including partners like Google, NVIDIA, and Mellanox Technologies. POWER9 processors are fabricated using IBM's advanced semiconductor processes and are central to several high-performance computing and enterprise systems.

Overview

The development of the POWER9 architecture was a collaborative effort within the OpenPOWER Foundation, which was formed to create an open ecosystem around the POWER Architecture. Key contributors included technology firms such as Google, which sought open hardware for its data centers, and NVIDIA, which collaborated on high-speed interconnects like NVLink. The first POWER9-based systems were announced in late 2017, with IBM positioning them for next-generation workloads in artificial intelligence and cloud computing. This generation marked a significant evolution from its predecessor, POWER8, with enhanced support for accelerators and improved memory bandwidth.

Architecture

The POWER9 microarchitecture introduces two distinct chip designs: the scale-out Sfora and the scale-up Cumulus. It implements a simultaneous multithreading (SMT) capability that can be configured for either four threads per core (SMT4) or eight threads per core (SMT8), providing flexibility for different workload profiles. A major architectural advancement is the integration of PCI Express Gen4 and up to 48 lanes of NVLink 2.0, enabling extremely fast communication with GPUs from NVIDIA and other accelerators. The memory subsystem supports both DDR4 memory and high-bandwidth Buffered Memory using proprietary technology from IBM.

Implementations

POWER9 processors are implemented in a range of systems from IBM and other OpenPOWER Foundation members. IBM's flagship servers, such as the IBM Power Systems AC922 and the IBM Power Systems E980, are built around POWER9 chips. Companies like Wistron and Inspur have also produced OpenPOWER-based servers under the Open Compute Project guidelines. Furthermore, the U.S. Department of Energy's exascale computing initiatives, including the Summit (supercomputer) and Sierra (supercomputer) at Oak Ridge National Laboratory and Lawrence Livermore National Laboratory, respectively, are powered by POWER9 processors coupled with NVIDIA Volta (microarchitecture) GPUs.

Performance

Performance benchmarks for POWER9 systems have demonstrated significant advantages in memory bandwidth and I/O throughput compared to contemporary x86-64 architectures. The Summit (supercomputer) held the title of the world's fastest supercomputer on the TOP500 list, showcasing the architecture's capability for computational science and modeling and simulation. The high-speed NVLink interconnect reduces latency for data movement between CPU and GPU, which is critical for machine learning and computational fluid dynamics applications. Independent analyses by organizations like the SPEC (organization) have recorded strong results on integer, floating-point, and throughput-oriented workloads.

Software support

The software ecosystem for POWER9 is supported by major Linux distributions, including Red Hat Enterprise Linux, SUSE Linux Enterprise Server, and Ubuntu (operating system). The OpenPOWER Foundation has fostered porting efforts for key open-source projects, ensuring compatibility with stacks for big data platforms like Apache Hadoop and Apache Spark. Development tools from the GNU Compiler Collection and the LLVM project provide native compilation support, while IBM offers its own IBM XL C/C++ Compilers. Virtualization is managed through the PowerVM hypervisor and the open-source Kernel-based Virtual Machine (KVM) for Linux.

Market and applications

POWER9 processors target high-value segments of the enterprise and high-performance computing markets. Primary applications include enterprise resource planning systems like SAP SE's SAP HANA, where large memory capacities are beneficial. Within the public cloud, offerings from IBM Cloud and Google Cloud Platform provide virtual machines on POWER9 infrastructure. The architecture is also pivotal in government and research institutions for projects such as the Square Kilometre Array radio telescope. Competition primarily comes from Intel Xeon and AMD Epyc processors in the server market, with POWER9 differentiating through its open ecosystem and accelerator-focused design.

Category:Microprocessors Category:IBM microprocessors Category:OpenPOWER Category:2017 in computing