Supercomputers

1. Daniel Shin CS 147, Section 1 April 29, 2010 Supercomputers

2. What is a Supercomputer • A computer that is at the frontline of current processing capacity, particularly speed of calculation • Today's supercomputer tend to become tomorrow's ordinary computer • Designed to perform complex calculations at super high speeds which would require a year or longer for a normal computer

3. Uses of Supercomputers • Used for highly calculation-intensive tasks • Problems involving quantum physics • Weather forecasting • Climate research • Molecular modeling • Physical simulations

4. History of Supercomputers • Supercomputers were introduced in the 1960s • They were designed primarily by Seymour Cray at Control Data Corporation (CDC) • Early machines were basically very fast scalar processors Cray-2 supercomputer Cray-1 supercomputer

5. Measuring Performance • FLOPS (FLoating point Operations Per Second) • Usually prefixed by an SI unit of magnitude: megaFLOPS, gigaFLOPS, teraFLOPS, petaFLOPS, exaFLOPS • Supercomputers are projected to reach 1 exaFLOPS (EFLOPS) in 2019 LINPACK Benchmark • A software library for performing numerical linear algebra on digital computers written in FORTRAN

6. Comparisons • 3.6GHz Pentium 4 • 1 gigaFLOPS (GFLOPS) 1.8GHz Opteron • 3 gigaFLOPS (GFLOPS) IBM Roadrunner • 1.1 petaFLOPS (PFLOPS) Cray Jaguar • 1.75 petaFLOPS (PFLOPS)

7. Supercomputer Challenges • Generates large amounts of heat and must be cooled • Information cannot move faster than the speed of light between two parts of a supercomputer • Seymour Cray's supercomputer designs attempted to keep cable runs as short as possible for this reason, hence the cylindrical shape of his Cray range of computers • Supercomputers consume and produce massive amounts of data in a very short period of time

8. Supercomputer Challenges (cont.) • Technologies developed for supercomputers include: • Vector processing • Liquid cooling • Non-Uniform Memory Access (NUMA) • Striped disks (the first instance of what was later called RAID) • Parallel filesystems

9. Seymour Roger Cray • Born September 28, 1925 in Chippewa Falls, Wisconsin • His father was a civil engineer who is said to have fostered Cray's interest in science and engineering • Cray's passion for building scientific computers led him to help start Control Data Corporation (CDC) in 1957 • Recognized as “the father of supercomputing” “Anyone can build a fast CPU. The trick is to build a fast system.” – Seymour Cray

10. Cray Computers • Cray is said to have frequently cited two important aspects to his design philosophy: remove heat, and ensure that all signals that are supposed to arrive somewhere at the same time do indeed arrive at the same time • Cray was also said to have been proud of the cushions that surrounded his cylindrically shaped computers, atop the power supplies • Cray Inc. is a supercomputer manufacturer based in Seattle, Washington • It was founded in 1972 by computer designer Seymour Cray

11. Cray Computers (cont.) • CDC 1604 • The CDC 1604 was a 48-bit computer designed and manufactured by Seymour Cray and his team at the Control Data Corporation • The 1604 is known as the first commercially successful transistorized computer • Cray-1 • The Cray-1 was a supercomputer designed, manufactured, and marketed by Cray Research • One of the best known and most successful supercomputers in history • The first Cray-1 system was installed at Los Alamos National Laboratory in 1976 Cray-1 with internals exposed

12. Cray Computers (cont.) • Cray Jaguar • In November 2009, the AMD Opteron-based Cray XT5 Jaguar at the Oak Ridge National Laboratory was announced as the fastest operational supercomputer • Cray Jaguar performed at a sustained processing rate of 1.75 petaFLOPS, beating the IBM Roadrunner for the number one spot on the TOP500 list • Future Development • Cray, Inc. announced in December 2009 a plan to build a 1 exaFLOPS (EFLOPS) supercomputer by the end of the 2010s Jaguar XT5

13. Flynn's Taxonomy, Computer Architectures • Single instruction single data steam (SISD) • Single instruction multiple data steams (SIMD) • Multiple instruction single data steam (MISD) • Multiple instruction multiple data steams (MIMD)

14. Flynn's Taxonomy, Computer Architectures (cont.)

15. Single instruction single data steam (SISD) • Single instruction single data steam (SISD) • A sequential computer which exploits no parallelism in either the instruction or data streams • Examples of SISD architecture: traditional uniprocessor machines like a PC or old mainframes

16. Single instruction multiple data steams (SIMD) • Single instruction multiple data steams (SIMD) • A computer which exploits multiple data streams against a single instruction stream to perform operations which may be naturally parallelized • Examples of SIMD architecture: an array processor or GPU

17. Multiple instruction single data steam (MISD) • Multiple instruction single data steam (MISD) • Multiple instructions operate on a single data stream • Uncommon architecture which is generally used for fault tolerance • Example of MISD architecture: the Space Shuttle flight control computer

18. Multiple instruction multiple data steams (MIMD) • Multiple instruction multiple data steams (MIMD) • Multiple autonomous processors simultaneously executing different instructions on different data • Distributed systems are generally recognized to be MIMD architectures