Does your stuff scale?Steven Holmeshttp://p.ota.to

Potato?

Does your stuff scale?

1. Django + Google App Engine

2. Scaling an organisation + culture

Non-technical

Scalability

Technical1. Load2. Functional

3. Organisational4. Geographic

Part 1

+

1. Auto-scaling

2. Services & APIs

3. No sysadmin

Why Google App Engine?

Just make good things.

App Engine: caveats

1. Sandbox

2. File system

3. Portability

What is it?• Django ported to NoSQL• GitHub, open source• Django 1.4, Django 1.5 beta

Pros• Familiar APIs• Portability• Works in production

How do you run it?• Clone repo(s)• ./manage.py runserver

Cons• Familiarity can be misleading• Can feel ‘heavy’ / kludgy

Django non-rel github.com/django-nonrel

What is it?• Lightweight skeleton• Django + App Engine models

Pros• “Best of both worlds”• NDB

• Automatic caching, structured data

How do you run it?• Clone repo• dev_appserver.py .

Cons• Learning curve• Portability

Djappengine github.com/potatolondon/djappengine

What is it?• Custom Django database backend wrapper for Django's MySQL backend

Pros• Fully supported Django

• Flexibility

• Unpredictable reporting

How do you run it?• Create a CloudSQL instance

• 'google.appengine.ext.django.backends.rdbms' in settings.py

• ./manage.py syncdb

Cons• More setup

• Possibly not as scalable as datastore?

App Engine + CloudSQL Search “Django + CloudSQL”

Part 2

Technical

Non-technical

Scalability

1. Load2. Functional

3. Organisational4. Geographic

+

• Planning

• Caching

• Offline tasks

• Preparation◦ Load tests

◦ Profiling (e.g. using app stats)

Scalability - Load

Technical

Non-technical

Scalability

1. Load2. Functional

3. Organisational4. Geographic

+

• Django!◦ Documentation, Community

• App Engine◦ Services & APIs

■ Memcache

■ Taskqueue, mapreduce■ Search

■ Email■ Images

◦ Versioning■ 10 testable versions per app■ http://0.myapp.appspot.com {live}■ http://1.myapp.appspot.com {not live}

■ http://some-feature-branch.myapp.appspot.com {not live}

■ A/B testing / traffic splitting◦ SDK

Scalability - Functional

Technical

Non-technical

Scalability

1. Load2. Functional

3. Organisational4. Geographic

+

• Be a minimalist• Remove bottlenecks & overhead• Just make good things.• Internal apps

Scalability - Organisational

• Be a minimalist• Remove bottlenecks & overhead• Just make good things.• Internal apps◦ e.g. wiki, recruitment, deployments, checklists

Scalability - Organisational

• Integrated and centralised◦ Google Apps domain

• Security◦ HTTPs

Technical

Non-technical

Scalability

1. Load2. Functional

3. Organisational4. Geographic

+

Just make good things.

Questions?

• Potato lab > http://p.ota.to/lab

• GitHub > github.com/potatolondon

• App Engine > developers.google.com/appengine

• Django non-rel > django-nonrel.org