After you have opened up your Firefox browser and the entered some thing like www.google.com the Domain Name System resolver sends back the web server IP address, but this dose have a price of time.
The DNS characteristically clocks up around 20-120 milliseconds to complete the DNS lookup request from the hostname chosen IP address location. The pour burning fox has to just site there and can't download the date packagers a web hostname server pending the DNS lookup has been fully accomplished its task, e.g. time to first bit.
The Domain Name System lookups are cached to provide improved webpage performance. The dater record storage system runs on dedicated caching web servers, controlled from your ISP internet-service-provider otherwise a LAN local-area-network, nevertheless in accompaniment to this the file caching also take place for each individuals home computer unit.
The DNS record information stays in your operating system DNS Client cache, the dnsrslvr.dllon Microsoft Windows operating systems. The majority of modern day web browsers include a webpage cache this is independent from your windows operating system file cache. Whilst internet explorer maintains a DNS-record within its own cache, IE has no necessitate asking the operating system for the request record.
The standard cache lookup setting for Internet Explorer is 30 minutes, set with the DnsCacheTimeout registry configuration. The Firefox default cache DNS lookups that are set for 1 minute will be changed by Fasterfox to 1 hour, controlled by the network.dnsCacheExpiration data setup configuration.
At the point were the cache on the client side DNS is empty, both Internet Explorer and the windows system, its quantity figure of DNS lookup resolutions are equal to the number of unique web severs hostnames in your Blog web page. This includes all http requests used in the page's URL, Java, images or script files, and stylesheets, Adobe shockwave Flash objects, any that is required from another source.
The best practice for rocket speed web page performance is to reduce the requests, but having only 1 would be as bad as having 20 of them.
Dropping down your sites page quantity of unique hostnames will equally decrease the amount of name lookups to be implemented by the DNS server.
Sinking the amount of unique web host sever names would-be a decrease in the total number of parallel requests downloading that is happens on your website.
Try to steer clear of large amounts of DNS lookups, they really do cut the response download time, but reducing parallel downloads may increase download response period.
It's really best to do a server waterfall test, to see how your site is loaded, you can only get to things from one place a once.
I think it is good to divide the file components across four to nine hostnames but try not to have much more. Some people say 2 to 4 hostnames but there site will not be very interactive e.g. not nice Face book social network widgets or Youtube videos and so-on.
What is required is a nice loading balanced compromise sandwiched between the reducing of your DNS lookups along with permitting a lofty quantity of parallel sever downloads.
Q. How will Google reward me for this, rocket speed web page reduce DNS Lookups a fast site?
A. I got one of my kids sites speed down from 13 sec to about 4.5 sec and got about 35% increases in traffic.
SEO TIP there is no page that tells you how to make the best web page just snippets of help here and there.
