Website visitors have one expectation: outstanding Web
experiences. Increasingly, the most critical determinant
in delivering these experiences is a user’s browser —
of which there are many with complex applications, addons
and serving multiple devices, to boot.
But the cost of failing to optimize browser performance and
meet users’ expectations has never been higher with a recent
survey* finding that:
• 67 percent of users encounter a slow website a few times a
week or more;
• 46 percent say slow load times cause them to abandon sites
very frequently or somewhat frequently; and
• Over a third say slowness makes them less likely to return
to a site.
Clearly, optimal browser performance is a key to keeping
users on a website and, therefore, closer to conversion goals.
But what is causing performance problems for so many users?
Let’s explore a few Web trends to find some answers:
Increased Browser Market Fragmentation: Microsoft’s
Internet Explorer 8 (IE8) is a very popular browser but with
just 24 percent of the browser market share, it lacks the dominance
of earlier versions of IE. Those earlier versions and
other, competing options include Firefox, Safari, Chrome and
others. In total, these options account for more than threequarters
of all users.
Different browser platforms — as well as different versions
of the same platform — perform and behave in different ways.
Consider connections per hostname: The greater the number
of connections per hostname a browser can make, the faster a
page loads. Currently there is an eight-second difference in response
time between the fastest- and slowest-performing
browsers. With such a wide variation, businesses must select
performance optimization techniques suited to those browsers
that drive the most traffic and revenue, on a global basis — an
optimization technique that works well on one browser may
cause an adverse effect on another.
Mobile Web Uptake: Today, businesses not only have to
manage greater browser diversity on desktop computers but
also contend with new complexity brought on by the mobile
Web. With approximately 500 mobile browser/device combinations
in use throughout the world, the prospect of managing
performance across all (or even most) of them is
However, businesses that fail to optimize for the mobile
Web experience could miss out on the sizable customer reach
and revenue potential of this growing channel. For example,
Morgan Stanley recently made a prediction that mobile users
will outnumber desktop Internet users worldwide by 2014.
Also consider the fact that AT&T has experienced a 50 percent
increase in mobile data over the last three years. Despite this
growth, users expect the mobile Web to load almost as quickly
— if not faster — compared to the computer they use as home.
Any business serious about the mobile Web must prioritize
Feature-rich Applications Shift Responsibility to the
Today’s websites and applications have evolved to
rich composites; comprising of content and services delivered
from the datacenter as well as from other sources outside the firewall — content delivery networks, advertising networks,
video, shopping carts, Web analytics and ratings and review
systems, for example. A recent study of 3,000 companies
found that the average Web-based transaction involves 8.85
different third parties or hosts. The browser is responsible for
assembling all of these components and presenting them to
As applications grow richer (and by extension, heavier),
technologies like AJAX, Flash and Flex help maintain application
speed by enabling browsers to perform much of the application
work. Other industry advances like HTML 5 place
an even heavier burden on browsers by storing data on the
client side, easing server demand. Browsers have evolved from
a “rendering engine” to an “integration platform,” and are responsible
for over 60 percent of overall processing time, in
some cases. For this reason, front-end performance improvements
for key browsers often yield the highest payback for the
Below are a set of best practices for delivering superior performance
across browsers to take control of your site and your
Implement a comprehensive monitoring approach,
both pre- and post-deployment:
Businesses must monitor
real-time performance on all major browser types available
to users. Visual and functional testing should be automated
and conducted on a regular basis. This approach should include
both operational or synthetic monitoring of websites
and applications across top browsers as well as experiential or
real-user monitoring to capture what users and customers actually
Today, worldwide testing networks offer businesses a fast,
easy view into website and application performance across
more than 500 browsers and browser/device combinations,
from the real user perspective. This is important because as an
application leaves the datacenter it is supplemented by thirdparty
services and passes through local ISPs and mobile carriers
before ultimately being delivered to browsers and devices.
Problems can occur at any point of this Web application delivery
chain, and the user perspective is the key to identifying
problems, determining if they are browser-related (or not) and
implementing optimization techniques at the browser level.
Understand which browsers your visitors use, and
monitor what matters:
In an environment of limited resources,
most businesses can’t test and optimize across all
browsers, so they must focus on the issues that really matter.
If a company’s major source of business comes from Asia, for
example, it’s far more important to measure site performance
on IE6 — the most popular browser in that region — than the
more recent, yet less used IE7 and IE8. Businesses should not
waste energy on “edge cases,” such as browser versions that
represent insignificant portions of their audience. Instead, concentrate
on monitoring browsers with the highest ROI potential for the business (the same rule applies to mobile
browser/device combinations). Furthermore, businesses must
concentrate on the parts of the website that matter most: The
most popular content, highest revenue transactions and the
most complex rich Internet applications.
Focus on front-end performance improvements: These
efforts often deliver the most positive impact on user experience
while requiring less time and money than back-end projects.
Consider browser optimization techniques like domain
charding, which entails “fooling” a user’s browser into thinking
there’s more than one host. As a result, multiple connections
can be made to a host server at the same time, enabling
more objects to be downloaded simultaneously and thus creating
faster downloads for little extra time or money.
However, domain charding is an example of an optimization
technique that works well for some browsers but not others.
It is ideal for older browsers that are typically capable of
only two parallel connections at a time. In this scenario, if
three hosts are detected, six objects (versus only two) can be
downloaded at once. The technique is problematic for newer
browsers like IE8 and Google Chrome that enable up to six
parallel connections. For these browsers, three hosts detected
translate into 18 images downloaded at once — which often
overload servers and has the adverse effect of a Web performance
Measure the impact of peak traffic:
Since newer browsers
offer greater connection parallelism, businesses must understand
how this can impact overall site performance under
heavy load. Only then can they truly understand if their infrastructure
capacity is sufficient. The key is to combine load
generated from the cloud with load generated from real user
desktops — providing a sense of how users are actually experiencing
a website or application at the edge of the Internet,
from their very browser. Older load testing approaches (which
entail leveraging one’s own datacenter-based servers to stimulate
high traffic volumes) may miss the true impact of increased
connection parallelism on the user’s Web experience.
Browsers exert a huge influence on the quality of a user’s
Web experience. Ensuring performance across browsers and
browser/device combinations is both essential and challenging.
New approaches focused on the user’s experience combined
with a hierarchical prioritization of browsers (based on
page views coming into a website) are the keys to overcoming
complexity and maximizing Web performance, time and
resources in a multi-browser world.
About the Author: Matthew Poepsel is VP of Performance Strategies of Gomez, the
Web Performance Division of Compuware.
* “When Seconds Count”, conducted by Equation Research
on behalf of Gomez and released in September, 2010.