http://www.egeniq.cominfo@egeniq.com

@egeniq

Tweakers.net Developer Summit, March 24 2011Ivo Jansch / @ijansch

The Art of Scalability

What is Scalability?

“[...] Scalability is the ability of a system, network, or process, to handle growing

amounts of work in a graceful manner or its ability to be enlarged to accommodate that

growth.” - Wikipedia

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Different levels of scale

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Site Pageviews/month # Servers Views / server

Facebook 200B 30K 6.6M

Netlog 4B 600 6.6M

Hyves 6.5B 3000 2.1M

Tweakers 60M 15 4M

Nu.nl 340M 14 24M

(See end of slide deck for sources)

‣Content Delivery Network• http://www.akamai.com/

‣Search Engine• http://sphinxsearch.com/• (Also have a look at http://lucene.apache.org/solr/)

‣Database Replication

Some of the tools at Netlog

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‣Caching• http://memcached.org/

‣Lightweight webserver• http://nginx.org/

‣Automated deployment• http://puppetlabs.com/

Some of the tools at Hyves

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‣Content pre-generation

‣Varnish Edge Side Includes• http://www.varnish-software.com/

‣Distributed Job Queues• http://gearman.org/ *

* nu.nl uses a custom job queue but this is one I can recommend

Some of the tools at Nu.nl

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Some of the tools at Facebook

‣PHP -> C++ compiler• https://github.com/facebook/hiphop-php

‣Distributed Logging• https://github.com/facebook/scribe

‣NoSQL Storage• http://cassandra.apache.org/

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How can you scale?Start with the basics

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Scaling with Hardware

If you run your app on multiple servers today, would it work?

Typical problem areas:‣ Sessions

‣ Files

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Elasticity

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A scalable funnel

Load balancer

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WebServer

WebServer

WebServer

WebServer

WebServer

AppServer

AppServer

AppServer

Database Services

Load balancer

Load balancer

Logical/Functional partitioning

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Scalable Architectures

‣Service Oriented Architecture

‣Component Based Design

‣Abstraction

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Scalability in Software

‣Caching

‣Graceful Degradation

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Food for ThoughtScaling Wisely

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Food for thought

Remember, this talk is called:

“The Art of Scalability”

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This is Art

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“House of Stairs”M.C. Escher

But this is Art, too

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“Composition with Blue”

Piet Mondriaan

Moral of this story

Scalability is about the ability to scale.

Don’t scale prematurely.

Keep it simple.

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“You’re doing it wrong!”

“Scalability is the ability of a system, network, or process, to handle growing large amounts

of work in a graceful manner or its ability to be enlarged to accommodate that growth.”

20

Thank you! Questions?

http://www.egeniq.cominfo@egeniq.com

@egeniq

http://www.egeniq.comivo@egeniq.com

@ijansch

Sources

The slide with servers and pageviews was based on:

‣ http://cns.ucsd.edu/lecturearchive09.shtml#Roth (Facebook)

‣ http://technologie.hyves.nl/ (Hyves)

‣ http://www.slideshare.net/folke/netlog-what-we-learned-about-scalability-high-availability-430211 (Netlog)

‣ http://www.slideshare.net/peter_ibuildings/surviving-a-plane-crash (Nu.nl)

‣ http://tweakers.net/reviews/331/5/tweakers-punt-net-faq-plans-stats-servers-en-site-software.html (Tweakers)

Credits

The following Creative Commons pictures were used in this presentation:

‣ ‘Datacenter Work’ by Leonardo Rizzi - http://www.flickr.com/photos/stars6/4381851322/

‣ ‘Rubber Band Man’ by Abe Novy - http://flickr.com/photos/thenovys/3791884189/

‣ ‘You’re doing it wrong’ by Adam Swank - http://www.flickr.com/photos/adeepbreath/3952587062/