Book Image

Clojure Programming Cookbook

Book Image

Clojure Programming Cookbook

Overview of this book

When it comes to learning and using a new language you need an effective guide to be by your side when things get rough. For Clojure developers, these recipes have everything you need to take on everything this language offers. This book is divided into three high impact sections. The first section gives you an introduction to live programming and best practices. We show you how to interact with your connections by manipulating, transforming, and merging collections. You’ll learn how to work with macros, protocols, multi-methods, and transducers. We’ll also teach you how to work with languages such as Java, and Scala. The next section deals with intermediate-level content and enhances your Clojure skills, here we’ll teach you concurrency programming with Clojure for high performance. We will provide you with advanced best practices, tips on Clojure programming, and show you how to work with Clojure while developing applications. In the final section you will learn how to test, deploy and analyze websocket behavior when your app is deployed in the cloud. Finally, we will take you through DevOps. Developing with Clojure has never been easier with these recipes by your side!
Table of Contents (16 chapters)
Clojure Programming Cookbook
Credits
About the Authors
About the Reviewer
www.PacktPub.com
Preface

Benchmarking with Criterium, performance tips, and other tools


In this recipe, we will learn how to test, measure, and improve the performance of your application. We will show you a Clojure-based benchmark tool.

Getting ready

To use Criterium, we need to add the criterium library in your project.clj as follows:

(defproject performance-example "0.1.0-SNAPSHOT" 
  :description "FIXME: write description" 
  :url "http://example.com/FIXME" 
  :license {:name "Eclipse Public License" 
            :url "http://www.eclipse.org/legal/epl-v10.html"} 
  :dependencies [[org.clojure/clojure "1.8.0"] 
                 [criterium "0.4.4"]]) 

Then, restart your REPL.

How to do it...

Here, we will show you how to test the performance of your code using Criterium.

Using Criterium

Criterium is a micro benchmark tool for measuring the computation time of Clojure expressions.

It performs given expressions multiple times and reports statistical information including means and std-deviations of execution time. Criterium...