Does CDN really speeds up website?

[Zhana]

Without CDN

http://www.webpagetest.org/result/110119_KS_JSG/


With CDN

http://www.webpagetest.org/result/110119_FM_JW1/




Any comments, suggestions?


Thank you.

[optrexnz]

Whether a CDN speeds up your website or not depends on your location to the server. If you are local then no, but if you are on the other side of the world then yes.

If like me your server is in NZ and your customer base is in NZ its no benefit. If however I have a UK server and a global customer base it works well.

[Ryan Ashbrook]

CDN's don't have the overhead of PHP, MySQL, or anything else other than the actual webserver software and -maybe- a control panel.

[mat206]

Yes it does, really. Here's why. When a browser connects to your web server it will first download the html and then issue a series of file requests for various embedded media like javascript, images, etc. Depending on the browser these requests will be issued serially, meaning one at a time. Newer browsers are starting to embed the ability to perform multiple parallel connections to a single server as well in order to download content quicker however. In any case, if you split a site across multiple domains you are giving the browser the ability to make parallel connections and download many of your media files at the same exact time.

But then, this isn't really why you use CDNs.. CDNs typically distribute content on multiple servers throughout the world. Latency comes into play here.. let's say someone from Europe makes a single request to a server in the states and that round-trip time is 200ms. That adds a MINIMUM delay of 200ms to every request your browser sends out. If you could locate a server closer to you geographically you could achieve round-trip times of 80ms or sometimes less to get the same content.

And why else do you choose a CDN? Because it takes load off of your web server and allows it to exclusively handle PHP requests, which are huge CPU and memory hogs anyway.

The CDN you are using, however, doesn't seem to be doing it's job.

[Zhana]

I'm using MaxCDN. And server is not local to me optrexnz.

[Jaggi]

I'm using MaxCDN. And server is not local to me optrexnz.

It doesn't even have to be that local, forexample you can have a server in canada and be in the US and it not have that much of a diff but UK > USA tend to have a lot of lag although this has been vastly been improved based on the "old days".

[Gary.]

It can be quite usefull for high ping and long distance servers, Euro to USA for example, But then again thats why all servers have the option for keepalive so once they visit the page, Then the next pages will all be fine untill you clear your caches and such.

Now I have only tested this and was not keen,Reason is see it does allow more open connections so instead of the one IP connecting, It will allow more so it can grab the data fast for a quicker page load. Quite good yes but if your running behind a hardware firewall or your using a strict CSF, And you go of the guide then you will see CDN is not always the soloution as the IP will be limited on incoming connections, So in reality you will not gain anything, Just more cache files being written.

This is my point of view and others may say different but I only say what I have proven on active tests.

[surinp3]

So, just to ask a Q about my situation...

I have a server in the US. I choce the US because it was the best compromise.
My readers are located in Sweden, 75% and Thailand 25%.

Would MaxCDN improve my site-performance for the readers?

[Jinkler]

Yes.