Chromium Blog
News and developments from the open source browser project
Prerendering in Chrome
Tuesday, June 14, 2011
Google.com's new Instant Pages feature,
announced earlier today
, makes some sites appear to load almost instantly when you click on them from the search results page. The feature is enabled by prerendering, a technology that we built into the upcoming version of Chrome, currently in the Dev channel. You can see Instant Pages in action in this video:
What is prerendering? Sometimes a site may be able to predict with reasonable accuracy which link the user is most likely to click on next--for example, the 'next page' link in a multi-page news article. In those cases, it would be faster and better for the user if the browser could get a head start loading the next page so that when the user clicks the page is already well on its way to being loaded. That's the fundamental idea behind prerendering. The browser fetches all of the sub-resources and does all of the work necessary to display the page. In many cases, the site simply seems to load instantly when the user clicks.
Although Google.com is the most high profile site to use prerendering, it's a technology that is available to any site. Triggering prerendering well, however, is challenging to do correctly and will only be useful to a handful of sites that have a high degree of certainty of where their users will click next. Triggering prerendering for the wrong site could lead to the link the user
did click on
loading more slowly.
The vast majority of sites will automatically work correctly when a third party like Google.com asks Chrome to prerender them. If you're interested in testing how your page behaves when being prerendered you can use
this sample page
. If you want your page to behave differently, you can use Chrome's new experimental page visibility API to detect prerendering.
The
page visibility API
- which is in the early stages of standardization in the webperf working group - can help developers understand the visibility status of their page: whether it's in a foreground tab, a background tab, or being prerendered. This is still an experimental implementation and it may change or even be removed in the future, which is why for the time being we've prefixed the property names with "webkit.” Although the page visibility API is useful for detecting prerendering, it also has many other applications--for example, allowing a site to pause expensive physics calculations when the page isn't visible.
To learn more about the page visibility API and prerendering, check out the
Using the Page Visibility API
and
Web Developers' Guide to Prerendering in Chrome
articles.
Posted by Alex Komoroske
Labels
$200K
1
10th birthday
4
abusive ads
1
accessibility
1
ad blockers
1
ad blocking
2
android
1
anti abuse
1
anti-deception
1
benchmarks
1
beta
18
billing
1
birthday
4
blink
1
browser
2
browser interoperability
1
capabilities
6
capable web
1
cds18
2
cds2018
1
chrome
18
chrome ads
1
chrome apps
3
chrome dev summit
1
chrome dev summit 2018
1
chrome developer
1
Chrome Developer Center
1
chrome developer summit
1
chrome devtools
1
Chrome extension
1
Chrome Frame
1
Chrome lite
1
Chrome on Android
1
chrome privacy
2
chrome security
1
chrome web store
29
chromedevtools
1
chromeframe
3
chromeos
3
chromium
3
cloud print
1
coalition
1
coalition for better ads
1
css
1
dart
8
dashboard
1
Data Saver
2
Data saver desktop extension
1
day 2
1
deceptive installation
1
declarative net request api
1
design
1
Developer Program Policy
1
devtools
13
discoverability
1
emscriptem
1
enterprise
1
extensions
27
features
1
feedback
2
field data
1
frameworks
1
fund
1
funding
1
gdd
1
google earth
1
google io 2019
1
google web developer
1
googlechrome
12
harmful ads
1
html5
11
incognito
1
ios
1
javascript
5
lab data
1
lighthouse
1
linux
2
Lite Mode
1
Lite pages
1
loading interventions
1
loading optimizations
1
mac
1
manifest v3
1
mobile
2
na
1
native client
8
New Features
5
octane
1
open web
3
origin trials
2
pagespeedinsights
1
payments
1
performance
3
performance tools
1
play store
1
portals
2
privacy
1
progressive web apps
1
Project Strobe
1
protection
1
pwa
1
releases
3
removals
1
rlz
1
safe browsing
1
security
31
slow loading
1
spdy
2
speed
1
ssl
2
store listing
1
strobe
1
subscription pages
1
suspicious site reporter extension
1
tools
1
transparency
1
trusted web activities
1
twa
2
user data policy
1
v8
6
wasm
1
web
1
web apps
1
web assembly
1
web intents
1
web packaging
1
web request api
1
web.dev
1
webapi
1
webaudio
3
webgl
7
webkit
5
webmaster
1
webp
5
webrtc
5
websockets
5
webtiming
1
writable-files
1
yerba beuna center for the arts
1
Archive
2019
Aug
Jul
Jun
May
Apr
Mar
Feb
Jan
2018
Dec
Nov
Oct
Sep
Aug
Jul
Jun
May
Apr
Mar
Feb
Jan
2017
Dec
Nov
Oct
Sep
Aug
Jul
Jun
May
Apr
Mar
Feb
Jan
2016
Dec
Nov
Oct
Sep
Aug
Jun
May
Apr
Mar
Feb
Jan
2015
Dec
Nov
Oct
Sep
Aug
Jul
Jun
May
Apr
Mar
Feb
Jan
2014
Dec
Nov
Oct
Sep
Aug
Jul
Jun
May
Apr
Mar
Feb
Jan
2013
Dec
Nov
Oct
Sep
Aug
Jul
Jun
May
Apr
Mar
Feb
Jan
2012
Dec
Nov
Oct
Sep
Aug
Jul
Jun
May
Apr
Mar
Feb
Jan
2011
Dec
Nov
Oct
Sep
Aug
Jul
Jun
May
Apr
Mar
Feb
Jan
2010
Dec
Nov
Oct
Sep
Aug
Jul
Jun
May
Apr
Mar
Feb
Jan
2009
Dec
Nov
Sep
Aug
Jul
Jun
May
Apr
Mar
Feb
Jan
2008
Dec
Nov
Oct
Sep
Feed
Follow @ChromiumDev
Give us feedback in our
Product Forums
.
