Book Image

SOA Cookbook

By : Michael Havey
Book Image

SOA Cookbook

By: Michael Havey

Overview of this book

Table of Contents (14 chapters)
SOA Cookbook
Credits
About the Author
About the Reviewers
Preface

Summary


Simulation is an important activity early in the life cycle of an SOA application. Running simulations on skeletal process models can expose performance problems even before development has begun. It is widely supported by BPM modeling tools, where the focus is on balancing speed and labor cost. In SOA, the trade-off is between speed and capacity. Unfortunately, there are comparatively few SOA simulation tools.

Underlying simulation is the concept of the Poisson process, which models systems whose requests come from a large population of clients, each of which acts independently of the others. The four properties of the Poisson process are independent increments, stationary increments, the requirement that events occur one at a time, and the plinko effect (an event can occur at any point during the arrival interval).

In a Poisson process, the Poisson distribution measures the number of events that occur in an interval. The interarrival times of events are based on the...