Improving Network Performance in Computational Grid

Applications

Joel Daniels II

Department of Computer Science

University of New Hampshire

What is a Grid Computing Application?

• Coupling of the applications and resources• A virtual computer composed of geographically dispersed resources

• offers enormous computing power

Why France?

• Padico– Grid Computing

application provides support for multiple simultaneous message passing schemes

– Poor performance over WAN!

• The VTHD (Vraiment

Tres Haut Debit) Network

Plan of Attack

• Why:– TCP misinterpretation of packet loss over WAN

• Solution:– Multiple parallel sockets to bypass problem (the

network is not flooded)

• Approach:– Control design to debug client-server application– Padico Based client-server application to collect data

Utilizing Multiple Parallel Sockets

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Padico'sperformance

Conclusions:– Increased performance with

parallel sockets!!!– No extra performance

gained after obtain ceiling values. (towards 8.4)

– Extra overhead is added with the addition of each socket. Computations are lost in handling sockets.

– If no extra bandwidth gained the extra overhead will make performance drop.

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performancedifferences

Linear(performancedifferences)

Additional Research

• TCP Send and Receive Buffer Sizes

• Message block sizes

• Different flags for send and recv, write, and read function calls

• Contention

The Interns

Amine of Morocco

Let me give you a history lesson! Parikshit of India

Nitin of India (Amine and moi)

Working Atmosphere

Inside the lab: Café break 1 Café break 2 work a bit Lunch Café break 3 work some more Café break 4

The Smallest City With A Metro

Rennes and the People: Their pride The crepes!

Kings and Queens

The Castles!

Dizzying Heights

The Alps!

The City of Romance

...and of course...

PARIS!

Where are all the berets?!?

In the end...

...learned enough French to impress the ladies...

...became a preferred reader at CNN.com...

...and suffer from occasional cheese cravings.

I survived...

C’est la fin!

Merci Beaucoup!

Bonne soirée!