Book Image

Clojure High Performance Programming

By : Shantanu Kumar
Book Image

Clojure High Performance Programming

By: Shantanu Kumar

Overview of this book

<p>Clojure is a young, dynamic, functional programming language that runs on the Java Virtual Machine. It is built with performance, pragmatism, and simplicity in mind. Like most general purpose languages, Clojure’s features have different performance characteristics that one should know in order to write high performance code.<br /><br />Clojure High Performance Programming is a practical, to-the-point guide that shows you how to evaluate the performance implications of different Clojure abstractions, learn about their underpinnings, and apply the right approach for optimum performance in real-world programs.<br /><br />This book discusses the Clojure language in the light of performance factors that you can exploit in your own code.</p> <p>You will also learn about hardware and JVM internals that also impact Clojure’s performance. Key features include performance vocabulary, performance analysis, optimization techniques, and how to apply these to your programs. You will also find detailed information on Clojure's concurrency, state-management, and parallelization primitives.</p> <p>This book is your key to writing high performance Clojure code using the right abstraction, in the right place, using the right technique.</p>
Table of Contents (15 chapters)
Clojure High Performance Programming
Credits
About the Author
Acknowledgments
About the Reviewers
www.PacktPub.com
Preface
Index

Performance testing


Testing for performance requires that we know what we are going to test, how we want to test it, and what environment to set up for the tests to execute. There are several pitfalls to be aware of, such as a lack of near-real hardware and resources of production use, similar OS and software environments, diversity of representative data for test cases, and so on. Lack of diversity in test inputs may lead to monotonic branch prediction, which introduces bias in test results. Collecting enough performance test samples is a significant criterion to obtain a statistically meaningful data set and prevent skewing.

Test environment

Concerns about the test environment begin with the hardware representative of the production environment. Traditionally, the test environment hardware has been a scaled-down version of the production environment. A performance analysis done on a non-representative hardware is almost certain to skew the results. Fortunately, in recent times, thanks to...