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Hack 61. Eliminate Annoying Browser Stalls

Here's a method to
short-circuit the part of the web page that is stalling your
browser.

It doesn't happen often, but every once in a while, you visit a
web page that seems to take forever to load, or simply hangs and
never finishes loading. The problem often occurs because the web page
includes a picture, a button, an advertisement, or some other web
element from another server that your browser cannot reach or cannot
reach quickly.

These resources are slow to respond for a few reasons. Sometimes
there's a bottleneck on the Internet itself.
Sometimes a link to a button, picture, or ad points to an Internet
site that is overloaded and having trouble responding.

Sometimes a link to an off-site graphical element is pointing to an
address that is inexplicably difficult to resolve. You see, for every
domain name, such as oreilly.com, there are one
or more numeric Internet protocol (IP) addresses. Your browser needs
to ask a domain name server (DNS) for that IP address, and that
server might have to pass the request on to another server, and then
to another. Sometimes there's a bad link in the
chain, and your browser simply gets hung up waiting to find out the
numeric IP address.

This hack refers to a problem with a specific link or site. When Internet access in general seems slow, one thing you can do is go to http://www.internethealthreport.com/ to see the current status of various Internet access and router points. The poor performance could be caused by a router outage somewhere. It might have nothing to do with the speed of your personal access method to the Internet.

But when you visit a web page again and again for weeks and notice
that it consistently stalls, that's a sign that one
or more identifiable elements, such as a graphic or advertisement,
might be causing the stall. For this hack, assume the problem is with
a graphical button. In this case, the web site you are trying to view
does not contain the graphics file needed for that button to be
displayed. Instead, the web page includes an HTML instruction to get
the graphic for that button from another site. You can run into
trouble if the browser has trouble finding the IP address for the
site that contains the graphic. Or perhaps your browser
doesn't have fast access to the site that provides
the graphic, or your browser is blocked from accessing that site. The
bottom line is that your browser can stall when loading the web page
simply because it cannot get the graphical element from a remote
site. Some browsers might even refuse to finish loading the page
until the problem is resolved.

You can short-circuit this process so that it never has to contact
the problematic web site. The trick revolves around how your computer
translates domain names, such as oreilly.com, to
IP addresses.

The /etc/nsswitch.conf file determines how your
computer tries to resolve the address of a domain name. Examine your
/etc/nsswitch.conf file, and look for the line
that starts with the label hosts. For example, it
might look like this:

hosts:     DNS files

This tells your computer to check the DNS first, and if it cannot
find the IP address from the DNS, to try looking up the IP address in
your local file called /etc/hosts.

If the line looks more like the following, it checks the local file
/etc/hosts first, and then checks with a DNS if
it can't find the IP address from your local file:

hosts:     files DNS

In most cases, browsers are slow to load pages or stall on something
such as a graphical element, because the DNS is having trouble
resolving the domain name into an IP address.

8.8.1. Short-Circuit the DNS Request

You can short-circuit this process
in a few steps. First, make sure the line in
your /etc/nsswitch.conf file looks like the
latter example, where files precedes
DNS. If your
/etc/nsswitch.conf file places something other
than files first, rearrange the order to make sure
files comes first.

Next, determine the domain name that is causing your browser to load
a page slowly or get stuck loading a web page element.
Here's how to track down the troublesome site. Keep
your eye on the status bar in your browser. If you are experiencing
the kind of problem I've been describing, the status
bar usually reads something like "Looking up
or "Waiting for while is it slow or stuck. The status message won't
change until it can find or contact that site. (Be careful not to
move the mouse while you are waiting for the site to load, or you
might inadvertently clear this status message even though the problem
continues to exist.)

Suppose your browser is getting stuck loading a page, because it is
having trouble trying to figure out the IP address of a host such as