Upgrade to Pro
— share decks privately, control downloads, hide ads and more …
Speaker Deck
Features
Speaker Deck
PRO
Sign in
Sign up for free
Search
Search
Let's make this test suite run faster! - BeJUG
Search
dgageot
April 05, 2012
Programming
590
1
Share
Let's make this test suite run faster! - BeJUG
dgageot
April 05, 2012
More Decks by dgageot
See All by dgageot
Docker on Google Cloud Platform
dgageot
0
1.7k
Lightning Talk Mix-IT 2014
dgageot
0
810
CodeStory 2013 "La Selection Finale"
dgageot
0
770
Finale Code Story
dgageot
1
720
Le facilitateur, un rôle encore méconnu
dgageot
1
210
Mockito. Ecrire des tests unitaires est devenu simple.
dgageot
2
440
Git, la gestion de configuration qui vous veut du bien
dgageot
1
480
My own preferred testing techniques
dgageot
1
120
Let's make this test suite run faster
dgageot
1
77
Other Decks in Programming
See All in Programming
技術記事、AIに書かせるか、自分で書くか? 〜それでも私が自分の手で書く理由〜 / #QiitaConference
jnchito
2
1.1k
生成AI時代にこそ効くGo | Why Go Works in the Age of Generative AI
mom0tomo
8
2.9k
Why Laravel apps break—Mastering the fundamentals to keep them maintainable
kentaroutakeda
1
300
自動レビューエンジンの実装と運用 ~レビューのない世界へ~
kurukuru1999
2
280
JavaDoc 再入門
nagise
0
190
プラグインで拡張される Context をtype-safe にする難しさと設計判断
kazupon
2
400
inferと仲良くなる10分間
ryokatsuse
1
270
Agentic UI beyond Chats Architecture Patterns & Open Standards @ngMunich 05/2026
manfredsteyer
PRO
0
160
密結合なバックエンドから TypeScript のコードを生成する
kemuridama
1
370
Hive Metastoreを通して学ぶIceberg REST Catalog ― 仕様から実装まで
okumin
0
290
AIエージェントと協働するCLI開発 — BunとOpenClawで学んだこと
yoshikouki
1
220
権限チェックの一貫性を型で守る TypeScript による多層防御
mnch
4
890
Featured
See All Featured
Six Lessons from altMBA
skipperchong
29
4.3k
エンジニアに許された特別な時間の終わり
watany
107
240k
Java REST API Framework Comparison - PWX 2021
mraible
34
9.3k
Marketing to machines
jonoalderson
1
5.3k
From π to Pie charts
rasagy
0
190
DevOps and Value Stream Thinking: Enabling flow, efficiency and business value
helenjbeal
1
200
How People are Using Generative and Agentic AI to Supercharge Their Products, Projects, Services and Value Streams Today
helenjbeal
1
190
How to build a perfect <img>
jonoalderson
1
5.5k
Evolving SEO for Evolving Search Engines
ryanjones
0
210
How to Grow Your eCommerce with AI & Automation
katarinadahlin
PRO
1
190
From Legacy to Launchpad: Building Startup-Ready Communities
dugsong
0
220
The World Runs on Bad Software
bkeepers
PRO
72
12k
Transcript
Let's make this test suite run faster!
David Gageot Freelance developer @dgageot javabien.net
Why make a test suite run faster?
“ I firmly believe it can make your product better.
Faster to test leads to faster to write, deploy and use ” Anonymous bearded freelance developper
You test early and often. Right?
Continuous integration?
Continuous testing?
Continuous deployment?
Testing a lot can lead to waiting a lot
How wants his coding room to look like
Test suite duration can be contained
Jenkins slaves to the rescue
Jenkins slaves to the rescue. not.
Why complicated when it can be simple?
I’ll share a few easy tricks
“ I firmly believe it can make your product better.
Faster to test leads to faster to write, deploy and use ” Anonymous bearded freelance developper
How can we accelerate the tests? The Cheater The Lazy
The Cheater
Buy a faster machine. Tests are cpu/
Thank you Q/A
BUT single threaded tests get slower 0 25 50 75
100 2007 2008 2009 2010
Use all the cores with Maven3 mvn -T1 clean install
: 5:05s mvn -T4 clean install : 3:10s Beware of tests with side effects
It’s not just me
Use all the cores with JUnit/TestNG Beware of tests with
side effects
That’s it for cheaters No silver bullet
The Lazy
Delete useless tests It’s so simple, we don’t do it...
Even better, delete dead code
Even better, delete dead code Leads to deleting even more
useless tests
Work in a sandbox In-memory database H2 behaves much like
MySql As simple as changing an xml file The database is slow
It’s Not only SQL If going for NoSQL, choose a
server that can run in-process eg. Voldemort The network is slow
In-memory SMTP Server SubEtha SMTP
Abstract the filesystem Apache VFS (Virtual File System) Spring Resource...
In-memory everything As a bonus, tests will run smoother
Of course all of these are easier to setup at
the beginning of a project
The
5 minutes a day can make a difference
Don’t test business rules in integration Unit tests are often
a better place
Not the same scale of speed 10sec .01sec
Action #1 - Break the longer integration Into one faster
integration test and a lot of small
Action #2 - Mock the slowest layers Mocks are not
just for unit tests eg. with Spring and Mockito spies
Action #3 - Don’t test through the Selenium is often
overkill «But my application is complex!» «My users want complex features, My users want Ajax» «I need to test browser compatibility!»
Really?
Complexity has a cost That you pay each time tests
run
Test through the browser the strict Unit test Javascript
Action #4 - Sometimes be old school write (easier to
test) server-side code
Thank you Q/A
One more thing™ Action #0 - Simplify and optimize your
code Tests will run faster Keep that one secret...
Thank you Q/A