Tech Talk on Cloud Computing
-
Upload
itviec -
Category
Technology
-
view
302 -
download
3
description
Transcript of Tech Talk on Cloud Computing
Reaching for the cloud3 ways that the cloud will change the way you develop software
Atlassian NirajBhawnani
What is the cloud?
• Remote servers run applications and store your data
• Accessible over the internet
• Users need not care where the application is running or
where their files are hosted
• Examples of cloud companies:
What is the cloud?
Atlassian & the cloud
• We build software tools for issue tracking, collaboration,
continuous integration, and source control
Who is Atlassian?
• Founded in 2002 by 2
Sydney-siders
• ~600 employees in:
Who is Atlassian?
Who is Atlassian?
Atlassian’s Vietnamese Team, November 2013
• Atlassian started selling software for customers to install
on their own servers
• Customers would keep asking if we had a hosted
solution
• In 2011, Atlassian OnDemand was born
• 41,150 VMs
• 5,640 CPU cores
• 58 TB RAM
• 368 TB Disk
Why is everything moving to the cloud?
• Great for business. One time payments become regular
payments
Why move to the cloud?
Confluence BTF vs. OnDemand
100 user license = $4000
Assuming an upgrade every 2 years:
BTF = $4000
100 user license = $300/month
OnDemand = $300 × 2 × 12= $7200
• Cheaper for customers – no staff or hardware required
Why move to the cloud?
Confluence BTF vs. OnDemand
100 user license = $4000
Staff/hardware = $70000/yr
Cost every 2 years:
BTF = $70000 × 2 + $4000= $144000
100 user license = $300/month
No staff/hardware = $0/yr
OnDemand = $300 × 2 × 12= $7200
• Always accessible via the internet
• Full control of the application server environment
Why move to the cloud?
Delivering software to the cloud
Traditional delivery pipeline
Production
Merge code QA Verification Staging deployment
& verification
Build Release
Manual Task
Automatic Task
Continuous Delivery Pipeline
Production
Merge code Continuous Integration
(Build & Test)
Manual Task
Automatic Task
How will the cloud change the way you
build software?
1. Incremental delivery
• Waterfall model does not work for cloud software
• Deliver features in small increments instead of “big bang
releases”
• Good for customers: they get features faster
• Good for you: less investment before validation
Incremental Delivery
• Start with a Minimum Viable Product (MVP)
• Simplest version of the feature that still adds value for users
• Example: Facebook Photos
• MVP allows users to just upload and view photos
Incremental Delivery
• Then deliver incrementally in order of importance
• V1/MVP: Upload and view standard definition photos
• V2: Face tagging
• V3: Video support
• V4: High definition photos & full screen mode
• V5: Automatic face detection
Incremental Delivery
What to do when the MVP is too big?
• Atlassian calls them “dark features”
• Wrap the feature in some condition and provide a way to
switch the condition on and off
• Also provide a way for tests to turn them on/off
• Eliminates the need for long lived code branches
Feature Switches
• Also allows us to deploy features to a subset of users
• Can be used to test more risky features without upsetting
too many users
Feature Switches
All users
Experiment
Group
Control
Group
2. Automation
• Since there might not be a manual verification step, we
must write a lot of automated tests to verify the system:
• Unit tests
• Integration tests
• Smoke tests
Automated Testing
• Automated tests need to run for every commit on every
branch
• Branches can be merged automatically or manually
• Automatic deployment when the main branch passes
• Tools: Atlassian Bamboo, Hudson, Cruise Control
Automated Testing
Automated Testing
• Check in code
• Build runs:
• Unit tests
• Integration tests
• Merge code
• Used to test individual units of source code in isolation
• Can run very very fast
• Might miss some bugs
• E.g. JUnit, Mockito, QUnit, etc.
Unit Tests
• Tests the whole product by functionality
• Runs slowly
• Selenium tests to drive the UI
• Hamcrest/JUnit to do assertions
Integration Tests
• Similar to integration tests
• Runs on one or more staging servers with real data that
has been upgraded
• Verifies that the data is intact and that basic functionality
still works
• Also uses Selenium
Smoke Tests
• Test code sends commands to Selenium Server
• Selenium Server starts a browser
• Selenium Server sends commands to the browser
• Type in this form
• Click the submit button
• Is this element visible?
Selenium
Test codeSelenium
Server
Web
Browser
• Since you need to write a lot of tests, you need to reuse
as much code as possible
• Write “page objects” that represent each page and “page
components” that represent shared components (e.g.
header and navigation)
Selenium
• Example code (Selenium with page objects):
Selenium
@Testpublic void testQuickSearchWithResults(){
viewPage = product.login(User.TEST, ViewPage.class, testData.page);QuickSearch quickSearch = viewPage.getHeader().getQuickSearch();SearchResultPage resultsPage = quickSearch.doSiteSearch(searchWithResults);Poller.waitUntilTrue(resultsPage.hasMatchingResults());
}
• Deployments happen very frequently:
• : 25/day
• : 1/day
• : 1/week
• Updates need to be fast and automatic
• Usually a collection of custom software and scripts
Automated Deployment
3. Analytics
• Collect usage data from all instances and users in a
centralised place
• This can be a very large amount of data, you need to
use tools that can handle it:
• Graphite
• Amazon Redshift
Analytics
• Query the data to answer important questions:
• What features are people using?
• What features are people not using?
• How are the features being used?
• What kind of users are using what kind of features?
• Use the data to make important business decisions
Analytics
• You should come up with the list of questions before you
ship the feature. Why?
Analytics
• You should come up with the list of questions before you
ship the feature. Why?
• To answer some kinds of questions you may need to write
additional code.
Analytics
• Leverages the existing events system
• Support for client-side events
• Reporting via Graphite or Apache Hive
• Google Analytics
• Greenzone
Atlassian Analytics
Atlassian Analytics
Product
instance
Product
instance
Product
instance
Product
instance
Product
instance
…
Product
instance
Analytics
Server
Analytics
Server
UDP
Graphite
HiveAmazon
Redshift
Application Server
Atlassian Analytics
Web Browser
Google Analytics
Analytics Plugin
Application
code
Analytics
Server
Database
Server
Greenzone
Database
Hive, etc.
Java Event
Batched
AJAX
Daily SQL
Queries
UDP
HAMS
Sales information
• Hardware costs (particularly RAM) is the largest expense
• RAM usage can be reduced by:
• Multitenancy
• Microservices architecture
• Optimising code
Other Considerations
• Deployment should not cause downtime
• Upgrade a standby server
• Switch proxy to new server
• Store sessions in a central location e.g. database
• Users experience no downtime
Other Considerations
• Things don’t always go as planned
• Always try to roll forward, never backward
• Have a procedure to deploy hotfixes in case of emergency
• Only revert to older versions as a last resort
Other Considerations
What should I do next?
• Consider moving your application to the cloud
• Deliver features incrementally
• Write a lot of automated tests
• Make deployment easy and automatic
• Use collected data to make business decisions
What should I do next?
• Learn more about Atlassian software
• Hear talks like this one about industry best practices
• Network with other professionals
• Free beer!
• https://aug.atlassian.com/
Thank You!
Questions?