Continuous Integrationin the Cloudwith HudsonKohsuke KawaguchiJesse GlickSun Microsystems, Inc.Hudson committers
Rise of Continuous Integration
> Offload from people, push to computers
2
$
time
computers
us
Spend more CPU power to help you
> … even if it only helps a little
> First on your laptops and workstations IDEs are at the forefront
> And then to the servers a.k.a. “Continuous Integration” More frequent build/test executions Static code analysis tools And more to come
3
Hudson
> Open-source CI server at java.net
> Emphasis on ease of installation and use “java -jar hudson.war” execution Configure everything from browsers
> Extensibility 140+ community-developed public plugins By 150+ contributors
> Estimated 13,000 installations4
https://hudson.dev.java.net/
It basically does builds and tests
> Check out the source code Subversion, Perforce, Git, Mercurial, CVS, …
> Do builds and/or tests Ant, Maven, MSBuild, shell script, …
> Record results Binary, test results, code coverage, static analysis
> Notify people E-mail, IM, RSS, tray apps, IDEs
5
Localized to 8 languages
6
And hopefully more to come…
7
8
Adoption in all kinds of businesses
9
Why Distributed Builds?
> You need to use multiple computers because… You need different environments You need isolation
> There’s only so much you can do with 1 computer
10
Before we talk about clouds…
> Going virtual doesn’t solve… Software installation problem Node failure problem Remote maintenance problem …
> What does Hudson do to help you with these?
11
Installing new slaves
> For first 20 or so slaves, we did it manually Insert CD, click, type, click, type, click, … But that doesn’t scale
> Then we automated Available as “Hudson PXE Plugin”
12
Automated System Installations
13
> Slaves Power on, hit F12 PC boots from network (PXE)
> Hudson + PXE plugin ISO images of OS
Automated System Installations
14
> Slaves Power on, hit F12 PC boots from network (PXE) Choose OS from menu Installs non-interactively
> Hudson + PXE plugin ISO images of OS
Your corporate IT guy & his DHCP server
Automated System Installations
> Supports OpenSolaris, Ubuntu, CentOS, Fedora Trivial with most Linux
> Cooperate with Windows, too
> Quite useful outside Hudson, too No more broken CD drives No more CD-Rs
15
Distributed builds with Hudson
> Master Serves HTTP requests Stores all important info
> Slaves 170KB single JAR Assumed to be unreliable Scale to at least 100
> Link Single bi-di byte stream No other requirements
16
How master and slaves start talking
> For Unix slaves, via SSH Only need SSH and JRE on slaves We just need a host name
17
How master and slaves start talking
> For Windows, DCOM We just need admin user name and password No manual intervention Works even from Unix masters
18
How master and slaves start talking
> Via Java Web Start When master cannot see slaves A separate socket connection is made
19
Automating JNLP launch
> Once started, can be installed as Windows service
20
Automating JNLP launch
> Emulate the JNLP client headless
21
$ java -jar slave.jar -jnlpUrl URL
Automated Tool Installation - JDK
> JDK from http://java.sun.com/ Hudson automatically chooses the right bundle Always up to date with new releases
22
Automated Tool Installation - Apache
> Ant and Maven from Apache
23
Automated Tool Installation - Custom
> Download arbitrary archive and unpack
24
Automated Tool Installation - Custom
> Run arbitrary shell commands Can have variants by OS
25
Automated Tool Installation - Extensible
> Write your own Simple Hudson extension Just write Java code to create tool on slave
> In progress: SCMs – Mercurial, … Install from Subversion
26
Heterogeneous Cluster Challenge
> Your builds/tests need to run in specific environment
> Dependency on individual nodes hurts utilization
27
WombatWindows test
WombatWindows test
Hudson Windows test
Hudson Windows test
Windows #1
Windows #1
jobs slaves
GlassFishWindows test
GlassFishWindows test
Windows #2
Windows #2
Solaris#1
Solaris#1
Hudson Solaris test
Hudson Solaris test
Labels to rescue
> Label is a group of slaves> Tie jobs to labels
28
WombatWindows test
WombatWindows test
Hudson Windows test
Hudson Windows test
Windows #1
Windows #1
jobs slaves
GlassFishWindows test
GlassFishWindows test
Windows #2
Windows #2
Solaris#1
Solaris#1
Hudson Solaris test
Hudson Solaris test
WindowsWindows
SolarisSolaris
Windows #3
Windows #3
Forecasting failures
> Hudson monitors key health metrics of slaves Low disk space, insufficient swap Clock out of synch Extensible
> Slaves go offline automatically> Catch problems before they break builds
30
Clean up mess after builds
> Kill runaway processes Daemons, background processes left by your build Works on Windows, Linux, Mac, and Solaris
31
Load Statistics Monitoring
32
When it’s time to add more slaves
33
Hudson made this extensible
> Hudson detects excessive workload> Hudson notifies plugins> Plugins can provision more slaves
… assuming that you have that infrastructure
34
35
Amazon EC2: The Good
> Pay as you go (10¢/h or so) Loads on Hudson tend to be spiky
> Programmable API> Instances launch at machine-speed> EC2 instances are forgetful
36
Amazon EC2: The Bad
> Your data is still inside your firewall Takes time to check out code … or to archive build artifacts Some data just can’t be moved
> EC2 instances are forgetful> Can your tests run in parallel?
37
Hudson EC2 plugin
> Built on top of typica*> What does it do?
Automatically provisions slaves on EC2 on demand Picks the right AMI depending on demand Starts slave agent Shuts down unused instances
38* http://code.google.com/p/typica/
Putting it all together
39
time
# of
exe
cuto
rs
capacity
usagequeue length
Hudson “Appliance” on EC2
> Run the master in the cloud too, if you like Hudson on stock OpenSolaris AMI Data stored persistently in Elastic Block Storage
Dynamically expandable thanks to ZFS Online, too
> Packaged as a wizard
40
41
42
> Hudson Hadoop plugin Just a few mouse clicks to install Turn every Hudson slave into a Hadoop node
> Distributed file system Automatic data replication (fault tolerant) Nice for storing old artifacts, logs, test records, …
> Map/reduce framework Large scale test results analysis / datamining More interesting work to be done in the future
43
Hudson Selenium Plugin
> Selenium Tests webapps by scripting browsers
> Selenium Grid Runs Selenium over a grid of computers
> Allow Hudson labels to specify where to start browsers
> Hudson & Selenium both need heterogeneous cluster
44
Selenium Grid
45
Hudson master(selenium hub)
Hudson slaves
Conclusion
> CI is here to stay We’ll continue to push more workload to servers
> Hudson makes this easy for you> Reap the benefit of a cluster in multiple ways
46
Resources
> http://hudson.dev.java.net/
> BOF-5105 “Hudson Community Meet up” Today 7:45pm same room
> Hudson booth inside Sun Pavilion
> Support Subscription [email protected]
47
Agenda
> Quick Hudson introduction> Doing distributed builds> How Hudson make distributed builds easier> Taking infrastructure to cloud
49
Setting up slaves
> Keeping slaves consistent is a good thing Particularly hard on heterogeneous environment
> General system administration tasks Network configuration Package installations for native tools Tools like Puppet or cfEngine are supposed to help
> Install build tools in the cluster Prepare tools on one file system rsync to everywhere
> This part of Hudson needs improvements50
Hudson EC2 plugin usage
> Tell Hudson your AWS account information
51
Hudson EC2 plugin usage
> Tell Hudson what AMIs you want to start
52