Yottaa Inc. 2 Canal Park 5th FloorCambridge MA 02141http://www.yottaa.com

An Experts Guideto making a website slow!!!

October 13th, 2011

Presented at O’Reilly’s Web 2.0 Expo in NYCBob Buffone, CTO - Yottaa

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Agenda

• The Web… Its complicated• Things that make a website slow• How can you make your website faster?

THE WEB… IT’S COMPLICATED

© 2011 Yottaa Inc. All Rights Reserved. 3

In between your visitors and you

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100+ factors…

Data centers

Major ISPs

CDNs Geography Last Mile Browsers Users

Performance uncertainty

3rd party assets/widgets

THINGS THAT MAKE YOUR WEBSITE SLOW

5© 2011 Yottaa Inc. All Rights Reserved.

Lots of Requests

• Product owners want rich websites– Rich in User Experience– Rich in Visual Presentation

• Achieving richness requires more resources to be downloaded to the client– CSS– HTML– JavaScript– Images

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Fat Resources

• Many of the resources that you need to load can be made fatter than required– HTML, CSS, JavaScript – Add lots of

comments and white space– Images

• Use images that are larger than displayed on the webpage

• Always use the highest quality settings

• Turn off gzip compression on your server

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Bad Servers

• There are many things that can make your servers slow– Poorly written code– Bad database design– Sharing a server with others– Old Servers– Not enough memory– Slow hard drives

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Randomness

• This is one of the hard things to add your site to make it slow.– Some of your users will experience a slow

website• It only takes one resource to slow down

your website.

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Do not use caching

• The web allows you to specify which resources the browser will cache on the visitor’s machine

• Not specifying cache control correctly means the browser will need to load resources for every page and

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3rd Party Plugins

• Bloggers love to make their websites slow using plugins.– Twitter, Facebook, Google Plus, LinkedIn– Photo plugins…

• Not utilizing asynchronous loading of 3rd party resources.

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Other things you can do

• Redirect from www to non-www using client-side– Use a 302 redirection instead of 301

• Add requests to resources that do not exist (404)• Run JavaScript code while your page is loading.• Only look at how fast your site is from your desktop• Think your website is fast enough• Do not test your websites performance• Think your developers would never do any of these

things

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HOW CAN YOU MAKE YOUR WEBSITE FASTER?

© 2011 Yottaa Inc. All Rights Reserved. 13

THANK YOU FOR YOUR TIME

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Yottaa

Bob (Buffone)Twitter: @RockstarappsCTO/Co-founder

www.yottaa.comTwitter: @Yottaa

Come and check us out in the Expo Booths!!!