E-Book Overview
To solve performance problems in modern computing infrastructures, often comprising thousands of servers running hundreds of applications, spanning multiple tiers, you need tools that go beyond mere reporting. You need tools that enable performance analysis of application workflow across the entire enterprise. That's what PDQ (Pretty Damn Quick) provides. PDQ is an open-source performance analyzer based on the paradigm of queues. Queues are ubiquitous in every computing environment as buffers, and since any application architecture can be represented as a circuit of queueing delays, PDQ is a natural fit for analyzing system performance.
Building on the success of the first edition, this considerably expanded second edition now comprises four parts. Part I contains the foundational concepts, as well as a new first chapter that explains the central role of queues in successful performance analysis. Part II provides the basics of queueing theory in a highly intelligible style for the non-mathematician; little more than high-school algebra being required. Part III presents many practical examples of how PDQ can be applied. The PDQ manual has been relegated to an appendix in Part IV, along with solutions to the exercises contained in each chapter.
Throughout, the Perl code listings have been newly formatted to improve readability. The PDQ code and updates to the PDQ manual are available from the author's web site at www.perfdynamics.com
E-Book Content
Analyzing Computer System Performance with Perl::PDQ Neil J. Gunther Analyzing Computer System Performance with Perl::PDQ Second Edition Neil J. Gunther Performance Dynamics Company 4061 East Castro Valley Boulevard Castro Valley, CA 94552 USA http://www.perfdynamics.com/ ISBN 978-3-642-22582-6 e-ISBN 978-3-642-22583-3 DOI 10.1007/978-3-642-22583-3 Springer Heidelberg Dordrecht London New York Library of Congress Control Number: 2011934511 ACM Codes: C.0, C.2.4, C.4, D.2.5, D.2.8, D.4.8, K.6.2 © Springer-Verlag Berlin Heidelberg 2005, 2011 This work is subject to copyright. All rights are reserved, whether the whole or part of the material is concerned, specifically the rights of translation, reprinting, reuse of illustrations, recitation, broadcasting, reproduction on microfilm or in any other way, and storage in data banks. Duplication of this publication or parts thereof is permitted only under the provisions of the German Copyright Law of September 9, 1965, in its current version, and permission for use must always be obtained from Springer. Violations are liable to prosecution under the German Copyright Law. The use of general descriptive names, registered names, trademarks, etc. in this publication does not imply, even in the absence of a specific statement, that such names are exempt from the relevant protective laws and regulations and therefore free for general use. Cover design: KünkelLopka Printed on acid-free paper Springer is part of Springer Science+Business Media (www.springer.com) This book is dedicated to the memory of my father Walter August Gunther, MIEAust, CPEng October 23, 1908 – November 16, 2010 Preface to Second Edition What’s New? It seems fitting that this new edition appears as we pass the centenary of the original paper by Erlang [1909], where he first introduced the concept of a queue. This edition incorporates a considerable number of new features compiled since the publication of the first edition in 2005. New Chapters and Partitioning The amount of additional material means the book now comprises four parts instead of three. In particular, Part I contains new chapters that present a more complete discussion of the underlying concepts used throughout this book. Improved Perl Formatting All listings have a highlighted format to aid readability of PDQ codes.