$30 off During Our Annual Pro Sale. View Details »
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
1
580
Let's make this test suite run faster! - BeJUG
dgageot
April 05, 2012
Tweet
Share
More Decks by dgageot
See All by dgageot
Docker on Google Cloud Platform
dgageot
0
1.7k
Lightning Talk Mix-IT 2014
dgageot
0
800
CodeStory 2013 "La Selection Finale"
dgageot
0
750
Finale Code Story
dgageot
1
710
Le facilitateur, un rôle encore méconnu
dgageot
1
200
Mockito. Ecrire des tests unitaires est devenu simple.
dgageot
2
430
Git, la gestion de configuration qui vous veut du bien
dgageot
1
470
My own preferred testing techniques
dgageot
1
110
Let's make this test suite run faster
dgageot
1
67
Other Decks in Programming
See All in Programming
Jetpack XR SDKから紐解くAndroid XR開発と技術選定のヒント / about-androidxr-and-jetpack-xr-sdk
drumath2237
1
190
ゆくKotlin くるRust
exoego
1
160
re:Invent 2025 のイケてるサービスを紹介する
maroon1st
0
150
Pythonではじめるオープンデータ分析〜書籍の紹介と書籍で紹介しきれなかった事例の紹介〜
welliving
3
610
Tinkerbellから学ぶ、Podで DHCPをリッスンする手法
tomokon
0
140
「コードは上から下へ読むのが一番」と思った時に、思い出してほしい話
panda728
PRO
39
26k
20251212 AI 時代的 Legacy Code 營救術 2025 WebConf
mouson
0
220
ローカルLLMを⽤いてコード補完を⾏う VSCode拡張機能を作ってみた
nearme_tech
PRO
0
170
從冷知識到漏洞,你不懂的 Web,駭客懂 - Huli @ WebConf Taiwan 2025
aszx87410
2
3.1k
LLMで複雑な検索条件アセットから脱却する!! 生成的検索インタフェースの設計論
po3rin
4
970
The Past, Present, and Future of Enterprise Java
ivargrimstad
0
360
Spinner 軸ズレ現象を調べたらレンダリング深淵に飲まれた #レバテックMeetup
bengo4com
0
190
Featured
See All Featured
Why Our Code Smells
bkeepers
PRO
340
57k
4 Signs Your Business is Dying
shpigford
186
22k
The Anti-SEO Checklist Checklist. Pubcon Cyber Week
ryanjones
0
28
Leading Effective Engineering Teams in the AI Era
addyosmani
9
1.4k
Measuring & Analyzing Core Web Vitals
bluesmoon
9
710
Put a Button on it: Removing Barriers to Going Fast.
kastner
60
4.1k
A better future with KSS
kneath
240
18k
Cheating the UX When There Is Nothing More to Optimize - PixelPioneers
stephaniewalter
286
14k
Mobile First: as difficult as doing things right
swwweet
225
10k
For a Future-Friendly Web
brad_frost
180
10k
How to optimise 3,500 product descriptions for ecommerce in one day using ChatGPT
katarinadahlin
PRO
0
3.4k
Utilizing Notion as your number one productivity tool
mfonobong
2
190
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