SHARCNET

Multicomputer Systems A multicomputer system comprises of a number

of independent machines linked by an interconnection network.

Each computer executes its own program which may access its local memory and may send and receive messages over the network.

The nature of the interconnection network has been a major topic of research for both academia and industry.

Distributed systems is one type of multicomputer system. What about others?

Multiprocessor Usage

• Scientific and engineering applications often require loops over large vectors e.g., matrix elements or points in a grid or 3D mesh. Applications include• Computational fluid dynamics• Scheduling (airline)• Health and biological modeling• Economics and financial modelling (e.g.,

option pricing)

Multiprocessor Usage

It should be noted that people have been developing “clusters” of machines that are connected using Ethernet for parallel applications.

The first such cluster (developed by two researchers at NASA) had 16 486 machines and was connected using 10 Mb Ethernet.

This is known as the Beowulf approach to developing a parallel computing and the clusters are sometimes called Beowulf clusters.

Sharcnet

UWO has taken a leading role in Canada in exploiting the concepts behind the Beowulf cluster.

High performance clusters: “Beowulf on steroids” Powerful “off the shelf” computational elements Advanced communications

Geographical separation (local use) Connect clusters: emerging optical

communications This is referred to as Shared Hierarchical Academic Research Computing Network or Sharcnet

Sharcnet

One cluster is called “Great White” Processors:

4 alpha processors: 833Mhz (4p-SMP) 4 Gb of memory 38 SMPs: a total of 152 processors

Communications 1 Gb/sec ethernet 1.6 Gb/sec quadrics connection

November 2001: #183 in the world Fastest academic computer in Canada 6th fastest academic computer in North America

Sharcnet

Great White (in Western Science Building)

Sharcnet

Extend “Beowulf” approach to clusters of high performance clusters

Connect clusters: “clusters of clusters” Build on emerging optical communications Initial configuration used optical equipment

from telecommunications industry Collectively a supercomputer!

Sharcnet

GUELPH

MACUWO

108

128

48

152

Optical communication

Clusters across Universities (initial cluster)

Sharcnet

In 2004, UWO received an investment of 56 million dollars from the government and private industry (HP) to expand Sharcnet.

With the new capabilities, Sharcnet could be in the top 100 or 150 of supercomputers.

Will be the fastest supercomputer of its kind – I.e.,a distributed system where nodes are clusters.

Sharcnet

Sharcnet Applications

Applications running on Sharcnet come from all sorts of domains including Chemistry Bioinformatics Economics Astrophysics Material Science and Engineering