http://stevesouders.com/docs/velocity-20090624.pptDisclaimer: This content does not necessarily reflect the opinions of my employer.

browser

browser

browser

smush.it

YSlow 2.0, Page Speed

JavaScript: The Good Parts

Velocity

this past year

how does your web feel?

why?

web site owners

1. don't know their web site is slow

2. don't know what is slow

3. don't know how to fix it

4. don't/can't prioritize the fix

my site slow? really??

easy instrumentation – Jiffy + AppEngine

community opt-in – a la Alexa

trends

messaging

visualizations – MSFast

what to fix

HttpWatch, Firebug Net Panel, Fiddler

sample size?

non-network – HTML, JS, CSS

how to fix it

YSlow, Page Speed, Pagetest, VRTA, neXpert, MSFast

sample size?

non-network – HTML, JS, CSS

backend

prioritizing the fix

tradeoffs, ROIBing: +1 second == -2.8% revenueGoogle: +400ms == -0.76%

searches/userShopzilla: faster: +7-12% revenue, -

50% nodes

wow versus infrastructure

technical constraints

BHAP

single threaded browsers

level of difficulty

connection speeds

mobile

ads

things are getting better

March 2007

March 2009

future Expires 26% 93%gzip CSS, JS 5/10 10/10sprites 2/10 9/10minify JS 4/10 9/10

AOL, eBay, Facebook, Google Search, Live Search, MSN, MySpace, Wikipedia, Yahoo, YouTube

don't give up

optimize locally

think globallycache "compiled" JS

multipart downloads

prefetching, preferred caching

WordPress, PHP, Dreamhost

fast-by-default

Internet infrastructure