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
Embed
Copy iframe code
Copy JS code
Copy link
Start on current slide
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
780
Finale Code Story
dgageot
1
730
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
82
Other Decks in Programming
See All in Programming
コンテキストの使い捨てをやめる — ビジネスルール駆動開発と miko —
ioki
0
240
Developing with AI Agents — Codex, Claude Code & Cowork Practical Guide
x5gtrn
PRO
0
1.3k
Hunting Vulnerabilities in Symfony with LLMs
vinceamstoutz
0
560
AI 輔助遺留系統現代化的經驗分享
jame2408
1
1k
Spec Driven Development | AI Summit Lisbon
danielsogl
PRO
0
210
代数的データ型って何が嬉しいの? #frontend_phpcon_do
kajitack
8
3.8k
Even G2とAWSで推しのエージェントを召喚しよう!
har1101
1
130
ふつうのFeature Flag実践入門
irof
8
4.2k
Honoでのサプライチェーン侵害対策 〜 3つのライブラリに学ぶ
yusukebe
7
1.5k
過去最大のMCPアップデート! 2026-07-28 RC版の謎に迫る
licux
6
400
肥大化するレガシーコードに立ち向かうためのインターフェース分離と依存の逆転 / JJUG CCC 2026 Spring
hirokunimaeta
0
630
軽量Java基盤の設計 DIコンテナに頼らない、長期保守と1秒起動の実現 JJUG CCC 2026 Spring
macha64
0
590
Featured
See All Featured
How to Ace a Technical Interview
jacobian
281
24k
Dealing with People You Can't Stand - Big Design 2015
cassininazir
367
27k
Between Models and Reality
mayunak
4
350
Primal Persuasion: How to Engage the Brain for Learning That Lasts
tmiket
0
380
How to make the Groovebox
asonas
2
2.2k
The Invisible Side of Design
smashingmag
301
52k
Chrome DevTools: State of the Union 2024 - Debugging React & Beyond
addyosmani
10
1.2k
Measuring Dark Social's Impact On Conversion and Attribution
stephenakadiri
2
220
Statistics for Hackers
jakevdp
799
230k
The browser strikes back
jonoalderson
0
1.3k
Build The Right Thing And Hit Your Dates
maggiecrowley
39
3.2k
How to Create Impact in a Changing Tech Landscape [PerfNow 2023]
tammyeverts
55
3.4k
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