Perl in Teh Cloud
What do you mean, “no wires”?

Scope
• Amazon Web Services Infrastructure products
• EC2, S3, EBS (SimpleDB, SQS, Elastic MapReduce N/A)
• What do you get from AWS? What don’t you get?
• Software packaging and deployment
• Use cases
• No code to see here, move along

What’s in EC2?
• On-demand compute power
• Controlled via a web service
• Free-form machines created with very little effort
• Computers without the metal bits

S3 - Simple Storage Service
• Storage accessible through web services
• Highly replicated
• Free data transfer within EC2

EBS - Elastic Block Service
• A hard disk, somewhere
• Format it however you like
• Attach to and mount on an instance
• Excellent random access performance
• As opposed to an instance’s storage, which is good for sequential
operations, like table scans.

The Problem
• Instances can drop out of the sky at any time
• Although this doesn’t happen often, *it will happen*
• An instance’s storage isn’t persistent across launches
• Machines are built from scratch on launch

Solutions
• Machine images
• Ye Olde Tarball
• EBS and snapshots

Solution - Machine Images
• Canonical machines
• Planning ahead
• Not very flexible
• Time-consuming

Solution - Tarball
• Hosted in S3
• Fetched and uncompressed on launch
• Set-up scripts written in whatever language you want
• local::lib

Solution - EBS
• Permanent storage
• One volume for one machine
• Snapshot it and create extra volumes on launch
• local::lib
• Easy to screw up

A Note About local::lib
• Oh look, code!
• Or perhaps not
• Each project can easily have its own $PERL5LIB
• No interference from other projects
• You can change the system-wide installation without fear of maiming
a project

A Note About local::lib
• Sinopsys
use local::lib; # sets up a local lib at ~/perl5
use local::lib '~/foo'; # same, but ~/foo
# Or...
use FindBin;
use local::lib "$FindBin::Bin/../support"; # app-local support library

A Note About local::lib
• And to easily install stuff where you want it:
# Install LWP and it's missing dependencies to the 'my_lwp' directory
perl -MCPAN -Mlocal::lib=my_lwp -e 'CPAN::install(LWP)'
# Install LWP and *all non-core* dependencies to the 'my_lwp' directory
perl -MCPAN -Mlocal::lib=--self-contained,my_lwp -e 'CPAN::install(LWP)'

Use Cases
• Testing and staging
• Scaling applications
• Disaster recovery
• No data center is a good data center

Use Case - Testing & Staging
• Machines are guaranteed to be exact replicas of production
• Never forget to update that module again
• Fire it up, do your thing, and shut it down
• Lead time measured in minutes

Use Case - Scaling
• Grow when you need to grow, shrink when you’re wasting resources
• Automated provisioning and de-commissioning
• Did I mention the lead time?

Use Case - Disaster Recovery
• Your main database went down
• A web server crashed
• Data replication
• Forget about lead times :)

Use Case - Data Center
• There isn’t one
• Stop paying for services you don’t use
• Aircon, racks, connectivity, power
• Remember when you forgot your ID or keys to the rack?

Net::Amazon::*
• Net::Amazon::S3
• Net::Amazon::S3::ACL
• Net::Amazon::S3::Tools
• Net::Amazon::SimpleQueue

See Also
• Bootstrapping local::lib
http://www.simplicidade.org/notes/archives/2009/05/locallib_bootst.html
• RightScale
http://rightscale.com/
• AWS for Eclipse

Q&A
• me@pedrofigueiredo.org
• http://www.slideshare.net/pfig/perl-in-teh-cloud
• http://groups.google.com/group/aws-cloud-user-group