IIT Professor Establishes New Mathematical Model for Reducing Data Access Delay

March 11, 2014

CHICAGO, Ill., March 11 — As the amount of data grows ever larger but memory speed continues to greatly lag CPU speed, Xian-He Sun, Distinguished Professor of Computer Science at Illinois Institute of Technology and creator of Sun-Ni’s law—one of three scalable computing laws along with Amdahl’s law and Gustafson’s law—has established a new mathematical model for reducing data access delay.

Called “Concurrent Average Memory Access Time (C-AMAT),” it promises to cut the penalty associated with accessing data and increase speed by up to 100 times through parallel memory access, which in turn will create a “break” in  the memory-wall problem. A paper on C-AMAT is forthcoming in the Institute of Electrical and Electronics Engineers (IEEE) Computer Society’s Computer magazine and can be viewed at http://www.computer.org/csdl/mags/co/preprint/06560068-abs.html.

“There’s no question the primary limits on computing performance—from mobile phones to supercomputers—are the costs associated with data movement,” said Andrew A. Chien, the William Eckhardt Professor in Computer Science and Senior Fellow in the Computation Institute at the University of Chicago, and Senior Computer Scientist at the Argonne National Laboratory.  Before moving to University of Chicago, Chien was vice president of research at Intel Corporation.

“Dr. Sun’s work attacks the critical problem of understanding and modeling data movement costs and systems performance and thus may enable better performing software (today) and improved hardware designs in the future.”

During the last four decades, CPU speed increase has been following Moore’s law, increasing 52 percent per year and doubling every 18 months. But memory speed is only increasing nine percent per year, and disk speed is even more behind, increasing an average of only six percent per year. Memory speed currently is about 400 times slower than CPU speed. That forms a wall for data movement and processing.

The data tsunami compounded with the memory-wall problem makes data management the primary concern of computing systems today, in terms of both performance and energy consumption. Computer science researchers increasingly are facing the need to rethink the design of computing systems from the conventional computing-centric view to a data-centric view.

While scientists search for solutions, they have found the value of the memory-bounded speedup model, or Sun-Ni’s law, established by Xian-He Sun and Lionel Ni in 1990. In 1989, Intel developed the first processor with on-chip caches in response to the memory-wall problem. Cache is a small but fast special hardware device to hold data temporarily and make it more easily accessible.

In response, Sun and Ni introduced the memory-bounded formulation stating that the computing speed will be bounded by the on-chip memory or on-chip cache. A quantitative mathematical memory-bound function is presented for the tradeoff between memory, computing, and the effectiveness of the algorithm design in utilizing the cache architecture. Sun-Ni’s law was introduced in advanced computer architecture textbooks in the 1990, and widely used in memory-bound-concerned algorithm design in the 2000s. In the 2010s, with the emergence of the big data problem, Sun-Ni’s law appeared in popular magazines such as PC Magazine.

Sun’s recent work on C-AMAT is the first formal mathematical model to promote and evaluate the concept of parallel memory for reducing data access delay via explicit parallel data access.

C-AMAT is a vital tool to mitigate the memory-wall effect and to improve memory system performance. There are only a handful fundamental formulas in computing architecture and algorithm design. AMAT is one of them. AMAT states that if the desired data is in cache (hit), then you get the data quickly; otherwise (miss), you get a cache miss penalty. Due to the memory-wall problem, the miss penalty will be big. So architecture and algorithm design focuses on reducing cache misses. With C-AMAT and parallel memory access, however, depending on if there is a hit occurring at the same time, a miss may or may not have a penalty. C-AMAT would change the focus of architecture and algorithm design from reducing cache misses to increasing data access parallelism. It provides a formulation to evaluate the effectiveness of the concurrency of each memory layer toward the final performance of parallel data access.

“The most profound research is not the design of the fastest algorithm for a given problem; it is revealing a fundamental computing property so hundreds or even thousands of algorithms can be developed upon it,” Sun said.

Sun has been working on memory access issues for 20 years. During this period, his research has been continuously supported by the National Science Foundation (NSF) and other government agencies.

Sun’s research is both application-driven and technology-driven. For the former, he and his research group have developed a series of software systems. These include the software packages of IOSIG: I/O Signatures Based Data Access Optimization, PFS-IOC: Server-side I/O-Coordination in Parallel File System, GHS: Grid Harvest Service, and Network Bandwidth Predictor (NBP), etc. For the latter, his contributions include the abovementioned Sun-Ni Law (1990), C-AMAT (2013), the algorithm-machine combination scalability, the general speed-up metric, an extended Amdahl’s law for multicore systems, and the memory Access Per Cycle (APC) performance metric, for measure memory parallelism (2011).

Sun is an IEEE Fellow for his contributions to memory-bounded performance metrics and scalable parallel computing, and a senior member of the Association for Computing Machinery (ACM). He has been the chair of the Department of Computer Science at IIT since fall 2009.

Founded in 1890, IIT is a Ph.D.-granting university offering degrees in engineering, sciences, architecture, psychology, design, humanities, business, and law. IIT’s interprofessional, technology-focused curriculum is designed to advance knowledge through research and scholarship, to cultivate invention improving the human condition, and to prepare students from throughout the world for a life of professional achievement, service to society, and individual fulfillment. Visit www.iit.edu.

—–

Source: Illinois Institute of Technology

Subscribe to HPCwire's Weekly Update!

Be the most informed person in the room! Stay ahead of the tech trends with industy updates delivered to you every week!

RSC Reports 500Tflops, Hot Water Cooled System Deployed at JINR

April 18, 2018

RSC, developer of supercomputers and advanced HPC systems based in Russia, today reported deployment of “the world's first 100% ‘hot water’ liquid cooled supercomputer” at Joint Institute for Nuclear Research (JI Read more…

By Staff

New Device Spots Quantum Particle ‘Fingerprint’

April 18, 2018

Majorana particles have been observed by university researchers employing a device consisting of layers of magnetic insulators on a superconducting material. The advance opens the door to controlling the elusive particle Read more…

By George Leopold

Cray Rolls Out AMD-Based CS500; More to Follow?

April 18, 2018

Cray was the latest OEM to bring AMD back into the fold with introduction today of a CS500 option based on AMD’s Epyc processor line. The move follows Cray’s introduction of an ARM-based system (XC-50) last November. Read more…

By John Russell

HPE Extreme Performance Solutions

Hybrid HPC is Speeding Time to Insight and Revolutionizing Medicine

High performance computing (HPC) is a key driver of success in many verticals today, and health and life science industries are extensively leveraging these capabilities. Read more…

Hennessy & Patterson: A New Golden Age for Computer Architecture

April 17, 2018

On Monday June 4, 2018, 2017 A.M. Turing Award Winners John L. Hennessy and David A. Patterson will deliver the Turing Lecture at the 45th International Symposium on Computer Architecture (ISCA) in Los Angeles. The Read more…

By Staff

Cray Rolls Out AMD-Based CS500; More to Follow?

April 18, 2018

Cray was the latest OEM to bring AMD back into the fold with introduction today of a CS500 option based on AMD’s Epyc processor line. The move follows Cray’ Read more…

By John Russell

IBM: Software Ecosystem for OpenPOWER is Ready for Prime Time

April 16, 2018

With key pieces of the IBM/OpenPOWER versus Intel/x86 gambit settling into place – e.g., the arrival of Power9 chips and Power9-based systems, hyperscaler sup Read more…

By John Russell

US Plans $1.8 Billion Spend on DOE Exascale Supercomputing

April 11, 2018

On Monday, the United States Department of Energy announced its intention to procure up to three exascale supercomputers at a cost of up to $1.8 billion with th Read more…

By Tiffany Trader

Cloud-Readiness and Looking Beyond Application Scaling

April 11, 2018

There are two aspects to consider when determining if an application is suitable for running in the cloud. The first, which we will discuss here under the title Read more…

By Chris Downing

Transitioning from Big Data to Discovery: Data Management as a Keystone Analytics Strategy

April 9, 2018

The past 10-15 years has seen a stark rise in the density, size, and diversity of scientific data being generated in every scientific discipline in the world. Key among the sciences has been the explosion of laboratory technologies that generate large amounts of data in life-sciences and healthcare research. Large amounts of data are now being stored in very large storage name spaces, with little to no organization and a general unease about how to approach analyzing it. Read more…

By Ari Berman, BioTeam, Inc.

IBM Expands Quantum Computing Network

April 5, 2018

IBM is positioning itself as a first mover in establishing the era of commercial quantum computing. The company believes in order for quantum to work, taming qu Read more…

By Tiffany Trader

FY18 Budget & CORAL-2 – Exascale USA Continues to Move Ahead

April 2, 2018

It was not pretty. However, despite some twists and turns, the federal government’s Fiscal Year 2018 (FY18) budget is complete and ended with some very positi Read more…

By Alex R. Larzelere

Nvidia Ups Hardware Game with 16-GPU DGX-2 Server and 18-Port NVSwitch

March 27, 2018

Nvidia unveiled a raft of new products from its annual technology conference in San Jose today, and despite not offering up a new chip architecture, there were still a few surprises in store for HPC hardware aficionados. Read more…

By Tiffany Trader

Inventor Claims to Have Solved Floating Point Error Problem

January 17, 2018

"The decades-old floating point error problem has been solved," proclaims a press release from inventor Alan Jorgensen. The computer scientist has filed for and Read more…

By Tiffany Trader

Researchers Measure Impact of ‘Meltdown’ and ‘Spectre’ Patches on HPC Workloads

January 17, 2018

Computer scientists from the Center for Computational Research, State University of New York (SUNY), University at Buffalo have examined the effect of Meltdown Read more…

By Tiffany Trader

Russian Nuclear Engineers Caught Cryptomining on Lab Supercomputer

February 12, 2018

Nuclear scientists working at the All-Russian Research Institute of Experimental Physics (RFNC-VNIIEF) have been arrested for using lab supercomputing resources to mine crypto-currency, according to a report in Russia’s Interfax News Agency. Read more…

By Tiffany Trader

How the Cloud Is Falling Short for HPC

March 15, 2018

The last couple of years have seen cloud computing gradually build some legitimacy within the HPC world, but still the HPC industry lies far behind enterprise I Read more…

By Chris Downing

Chip Flaws ‘Meltdown’ and ‘Spectre’ Loom Large

January 4, 2018

The HPC and wider tech community have been abuzz this week over the discovery of critical design flaws that impact virtually all contemporary microprocessors. T Read more…

By Tiffany Trader

Fast Forward: Five HPC Predictions for 2018

December 21, 2017

What’s on your list of high (and low) lights for 2017? Volta 100’s arrival on the heels of the P100? Appearance, albeit late in the year, of IBM’s Power9? Read more…

By John Russell

How Meltdown and Spectre Patches Will Affect HPC Workloads

January 10, 2018

There have been claims that the fixes for the Meltdown and Spectre security vulnerabilities, named the KPTI (aka KAISER) patches, are going to affect applicatio Read more…

By Rosemary Francis

Nvidia Responds to Google TPU Benchmarking

April 10, 2017

Nvidia highlights strengths of its newest GPU silicon in response to Google's report on the performance and energy advantages of its custom tensor processor. Read more…

By Tiffany Trader

Leading Solution Providers

Deep Learning at 15 PFlops Enables Training for Extreme Weather Identification at Scale

March 19, 2018

Petaflop per second deep learning training performance on the NERSC (National Energy Research Scientific Computing Center) Cori supercomputer has given climate Read more…

By Rob Farber

Lenovo Unveils Warm Water Cooled ThinkSystem SD650 in Rampup to LRZ Install

February 22, 2018

This week Lenovo took the wraps off the ThinkSystem SD650 high-density server with third-generation direct water cooling technology developed in tandem with par Read more…

By Tiffany Trader

AI Cloud Competition Heats Up: Google’s TPUs, Amazon Building AI Chip

February 12, 2018

Competition in the white hot AI (and public cloud) market pits Google against Amazon this week, with Google offering AI hardware on its cloud platform intended Read more…

By Doug Black

HPC and AI – Two Communities Same Future

January 25, 2018

According to Al Gara (Intel Fellow, Data Center Group), high performance computing and artificial intelligence will increasingly intertwine as we transition to Read more…

By Rob Farber

New Blueprint for Converging HPC, Big Data

January 18, 2018

After five annual workshops on Big Data and Extreme-Scale Computing (BDEC), a group of international HPC heavyweights including Jack Dongarra (University of Te Read more…

By John Russell

US Plans $1.8 Billion Spend on DOE Exascale Supercomputing

April 11, 2018

On Monday, the United States Department of Energy announced its intention to procure up to three exascale supercomputers at a cost of up to $1.8 billion with th Read more…

By Tiffany Trader

Momentum Builds for US Exascale

January 9, 2018

2018 looks to be a great year for the U.S. exascale program. The last several months of 2017 revealed a number of important developments that help put the U.S. Read more…

By Alex R. Larzelere

Google Chases Quantum Supremacy with 72-Qubit Processor

March 7, 2018

Google pulled ahead of the pack this week in the race toward "quantum supremacy," with the introduction of a new 72-qubit quantum processor called Bristlecone. Read more…

By Tiffany Trader

  • arrow
  • Click Here for More Headlines
  • arrow
Share This