Page Load Performance
#EdgeConf 3, Mar 2014

http://www.flickr.com/photos/sybrenstuvel/2468506922
I’m frustrated…

The web is too slow
http://www.flickr.com/photos/the_justified_sinner/3507390621

The web is too slow
http://www.flickr.com/photos/the_justified_sinner/3507390621

Too may sites are too slow
http://www.flickr.com/photos/the_justified_sinner/3507390621

- Minimise Latency!
!
- Minimise Round Trips!
!
- Minimise Blocking
We know how to make sites fast!

Maximise value from first round trip
Guardian divide page load into!
!
- Content!
!
- Enhancements!
!
- Leftovers

Browsers are doing a great job
http://www.flickr.com/photos/brianauer/2197218356/

HTTP/2

But we keep adding more and more to our pages
http://www.flickr.com/photos/70601645@N00/383984327

and including more render blocking requests
http://www.flickr.com/photos/timo/3995227

We can automate optimisation
http://www.flickr.com/photos/freshwater2006/693945631

We’ve got some great tools

We can measure in the visitor’s browser
- Page level timings!
!
- Resource level timings!
!
- User defined timing points

We need to move beyond ‘which pages are slow?’

To why are they slow?

To how do we fix them?

Performance is a facet of User Experience
http://www.flickr.com/photos/21218849@N03/8638895168

We need to design for it
http://www.flickr.com/photos/9760699@N08/3748770917

http://www.flickr.com/photos/communityfriend/2342578485
It’s just another constraint

We’ve come a long way…
http://www.flickr.com/photos/proimos/5452083285
…but we’ve still a way to go