The ACS-1 and ACS-360 are two related supercomputers designed by IBM as part of the IBM ''Advanced Computing Systems'' project from 1961 to 1969. Although the designs were never finished and no models ever went into production, the project spawned a number of organizational techniques and architectural innovations that have since become incorporated into nearly all high-performance computers in existence today. Many of the ideas resulting from the project directly influenced the development of the

IBM RS/6000 The RISC System/6000 (RS/6000) is a family of RISC-based Unix servers, workstations and supercomputers made by IBM in the 1990s. The RS/6000 family replaced the IBM RT PC computer platform in February 1990 and was the first computer line to see ...

and, more recently, have contributed to the

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(EPIC) computing paradigm used by

Intel Intel Corporation is an American multinational corporation and technology company headquartered in Santa Clara, California. It is the world's largest semiconductor chip manufacturer by revenue, and is one of the developers of the x86 seri ...

and HP in high-performance processors.

History

The ACS project began in 1961 as ''Project Y'' with a goal of “building a machine that was one hundred times faster than Stretch”. Initial work began at the

IBM Watson Research Center The Thomas J. Watson Research Center is the headquarters for IBM Research. The center comprises three sites, with its main laboratory in Yorktown Heights, New York, Yorktown Heights, New York (state), New York, U.S., 38 miles (61 km) north ...

. A number of significant computer pioneers contributed to the project, including John Cocke,

Herb Schorr In general use, herbs are a widely distributed and widespread group of plants, excluding vegetables and other plants consumed for macronutrients, with savory or aromatic properties that are used for flavoring and garnishing food, for medicinal ...

Frances Allen Frances Elizabeth Allen (August 4, 1932August 4, 2020) was an American computer scientist and pioneer in the field of optimizing compilers. Allen was the first woman to become an IBM Fellow, and in 2006 became the first woman to win the Turing ...

Gene Amdahl Gene Myron Amdahl (November 16, 1922 – November 10, 2015) was an American computer architect and high-tech entrepreneur, chiefly known for his work on mainframe computers at IBM and later his own companies, especially Amdahl Corporation ...

, and

Lynn Conway Lynn Ann Conway (born January 2, 1938) is an American computer scientist, electrical engineer and transgender activist. She worked at IBM in the 1960s and invented generalized dynamic instruction handling, a key advance used in out-of-or ...

. A decision by IBM in May 1968 to modify the project to support

S/360 The IBM System/360 (S/360) is a family of mainframe computer A mainframe computer, informally called a mainframe or big iron, is a computer used primarily by large organizations for critical applications like bulk data processing for t ...

compatibility resulted in the name change from ''ACS-1'' to ''ACS-360'' for the computer being designed. At its peak, the ACS-360 project involved over 200 engineers and staff. The ACS-360 project was canceled in May 1969; however, many of the innovations resulting from the project would eventually find direct realization in the

series of machines (later known as the

IBM System p The IBM System p is a high-end line of RISC (Power)/UNIX-based servers. It was the successor of the RS/6000 line, and predecessor of the IBM Power Systems server series. History The previous RS/6000 line was originally a line of workstations and ...

line of workstations and servers), apart from influencing the design of other machines and architectures.

Influence

Although neither the ACS-1 nor the ACS-360 was ever manufactured, the IBM Advanced Computing Systems group responsible for their design developed architectural innovations and pioneered a number of

RISC In computer engineering, a reduced instruction set computer (RISC) is a computer designed to simplify the individual instructions given to the computer to accomplish tasks. Compared to the instructions given to a complex instruction set comput ...

CPU design techniques that would become fundamental to the design of modern computer architectures and systems: * Aggressive reduction in the number of logic gate levels for pipeline stages to reduce the cycle time * Tight integration between processor and memory * Cache memory with streamlined I/O to/from cache * Compiler optimization techniques * Virtual-memory operating systems * Multiple instruction decode and issue (a first) * Use of a branch target buffer (a first) * Multithreading implemented in hardware (a first for IBM) * Dynamic instruction scheduling/

out-of-order execution In computer engineering, out-of-order execution (or more formally dynamic execution) is a paradigm used in most high-performance central processing units to make use of instruction cycles that would otherwise be wasted. In this paradigm, a proce ...

* Hardware

register renaming In computer architecture, register renaming is a technique that abstracts logical registers from physical registers. Every logical register has a set of physical registers associated with it. When a machine language instruction refers to a partic ...

* Instruction predication *

Level-sensitive scan design Within the field of electronics Level-sensitive scan design (LSSD) is part of an integrated circuit manufacturing test process. It is a DFT scan design method which uses separate system and scan clocks to distinguish between normal and test mode ...

(used by IBM) * Fixed-head hard disks * Air-cooled high-speed LSI circuits * Advanced simulation tools used in the design process

Notes

External links

IBM Advanced Computing Systems (ACS) — 1961–1969
— Documentation project for the IBM ACS-1 supercomputer maintained by Mark Smotherman {{IBM Advanced Computing Systems project Advanced Computing Systems project

History

Influence

Notes

Further reading

External links