The A64FX is a

64-bit In computer architecture, 64-bit integers, memory addresses, or other data units are those that are 64 bits wide. Also, 64-bit central processing units (CPU) and arithmetic logic units (ALU) are those that are based on processor registers, a ...

ARM architecture ARM (stylised in lowercase as arm, formerly an acronym for Advanced RISC Machines and originally Acorn RISC Machine) is a family of reduced instruction set computer, RISC instruction set architectures (ISAs) for central processing unit, com ...

microprocessor A microprocessor is a computer processor (computing), processor for which the data processing logic and control is included on a single integrated circuit (IC), or a small number of ICs. The microprocessor contains the arithmetic, logic, a ...

SPARC64 V The SPARC64 V (''Zeus'') is a SPARC, SPARC V9 microprocessor designed by Fujitsu. The SPARC64 V was the basis for a series of successive processors designed for servers, and later, supercomputers. The servers series are the SPARC64 V+, VI, VI+, ...

as Fujitsu's processor for

supercomputer A supercomputer is a type of computer with a high level of performance as compared to a general-purpose computer. The performance of a supercomputer is commonly measured in floating-point operations per second (FLOPS) instead of million instruc ...

applications. It powers the Fugaku supercomputer, ranked in the

TOP500 The TOP500 project ranks and details the 500 most powerful non-distributed computing, distributed computer systems in the world. The project was started in 1993 and publishes an updated list of the supercomputers twice a year. The first of these ...

as the fastest supercomputer in the world from June 2020, until falling to second place behind

Frontier A frontier is a political and geographical term referring to areas near or beyond a boundary. Australia The term "frontier" was frequently used in colonial Australia in the meaning of country that borders the unknown or uncivilised, th ...

in June 2022.

Design

Fujitsu collaborated with

ARM In human anatomy, the arm refers to the upper limb in common usage, although academically the term specifically means the upper arm between the glenohumeral joint (shoulder joint) and the elbow joint. The distal part of the upper limb between ...

to develop the processor; it is the first processor to use the ARMv8.2-A

Scalable Vector Extension AArch64, also known as ARM64, is a 64-bit version of the ARM architecture family, a widely used set of computer processor designs. It was introduced in 2011 with the ARMv8 architecture and later became part of the ARMv9 series. AArch64 allows p ...

SIMD instruction set with 512-bit vector implementation. It has "Four-operand FMA with Prefix Instruction", i.e. MOVPRFX instruction followed by 3-operand FMA operation (

, like

RISC In electronics and computer science, a reduced instruction set computer (RISC) is a computer architecture designed to simplify the individual instructions given to the computer to accomplish tasks. Compared to the instructions given to a comp ...

in general, is a 3-operand machine, with no space for four operands), which get packed into a single operation in the pipeline. For the processor the designer claim ">90% execution efficiency in (D, S, H) GEMM and INT16/8

dot product In mathematics, the dot product or scalar productThe term ''scalar product'' means literally "product with a Scalar (mathematics), scalar as a result". It is also used for other symmetric bilinear forms, for example in a pseudo-Euclidean space. N ...

". The processor uses 32 gigabytes of HBM2 memory with a bandwidth of 1 TB per second. The processor contains 16 PCI Express generation 3 lanes to connect to accelerators (hypothetical e.g.

GPUs A graphics processing unit (GPU) is a specialized electronic circuit designed for digital image processing and to accelerate computer graphics, being present either as a discrete video card or embedded on motherboards, mobile phones, personal ...

and FPGAs). The processor also integrates a TofuD fabric controller with 10 ports implemented as 20 lanes of high-speed 28 Gbit/s to connect multiple nodes in a cluster. The reported transistor count is about 8.8 billion. Each A64FX processor has four NUMA nodes, with each NUMA node having 12 compute cores, for a total of 48 cores per processor. Each NUMA node has its own level 2 cache, HBM2 memory, and assistant cores for non-computational purposes. Fujitsu intends to produce lower specification machines with reduced assistant cores.

Reliability, availability and serviceability Reliability, availability and serviceability (RAS), also known as reliability, availability, and maintainability (RAM), is a computer hardware engineering term involving reliability engineering, high availability, and serviceability design. The p ...

(RAS) capabilities are claimed, i.e. ~128,400 error checkers in total. In June 2020 the Fugaku supercomputer using this processor reached 442 petaFLOPS and became the fastest supercomputer in the world.

Implementations

Fujitsu designed the A64FX for the Fugaku. Fugaku held the rank of the fastest supercomputer in the world by

rankings. Fujitsu intends to sell smaller machines with A64FX processors. Anandtech reported in June 2020 that the cost of a PRIMEHPC FX700 server, with two A64FX nodes, was (c. ).

Cray Cray Inc., a subsidiary of Hewlett Packard Enterprise, is an American supercomputer manufacturer headquartered in Seattle, Washington. It also manufactures systems for data storage and analytics. Several Cray supercomputer systems are listed ...

is developing supercomputers using the A64FX. The supercomputer is being built for a consortium in the

United Kingdom The United Kingdom of Great Britain and Northern Ireland, commonly known as the United Kingdom (UK) or Britain, is a country in Northwestern Europe, off the coast of European mainland, the continental mainland. It comprises England, Scotlan ...

, led by the

University of Bristol The University of Bristol is a public university, public research university in Bristol, England. It received its royal charter in 1909, although it can trace its roots to a Merchant Venturers' school founded in 1595 and University College, Br ...

and also including the

Met Office The Met Office, until November 2000 officially the Meteorological Office, is the United Kingdom's national weather and climate service. It is an executive agency and trading fund of the Department for Science, Innovation and Technology and ...

, using the Fujitsu processors. It is an upgrade to the Isambard supercomputer which was built with the Marvell ThunderX2, another ARM architecture microprocessor.
Ookami
is an open testbed system supported by NSF run by

Stony Brook University Stony Brook University (SBU), officially the State University of New York at Stony Brook, is a public university, public research university in Stony Brook, New York, United States, on Long Island. Along with the University at Buffalo, it is on ...

and the

University at Buffalo The State University of New York at Buffalo (commonly referred to as UB, University at Buffalo, and sometimes SUNY Buffalo) is a public university, public research university in Buffalo, New York, Buffalo and Amherst, New York, United States. ...

providing researchers access to A64FX processors.

References

{{Application ARM-based chips Computer-related introductions in 2019 ARM processors Fujitsu microprocessors 64-bit microprocessors

Design

Implementations

See also

References