Help me to Analyse the Performance and get to the Root cause

[Anton Chigurh]

(05-14-2014 01:39 PM)GreenGecko Wrote:  
OK, I've been writing English natively now since I was about 5... so just on half a century. I've got the hang of it now.

I'll take just one of your statements:

"CDNs cannot improve performance of a site that isn't optimized, and if you do optimize it, you don't need a CDN."

Well, yes they can, and yes you do. By...

1. Delivering content from a local node. Less latency = faster delivery.
2. Delivering content from a fat pipe. Delivered at the available bandwidth of the client, not what percentage of the server's bandwidth is available for that particular client = faster delivery.
3. Reducing the load on the client's server frees up the server to deliver only the html framework of a dynamic page. Whilst the delivery of static content is not at all CPU intensive, it directly affects the available bandwidth to deliver it.

So yes, you do need a CDN to deliver graphically rich content. You've handed the job over to a supplier who specialises in it.
And yes, you do need a CDN to protect the available bandwidth on your server.

Maybe you're based in the USA, and don't see these things. It would explain your quoting Spiro Agnew at me. However, the OP - and myself - certainly aren't.

You are wrong. Maybe it's you who should learn to read. And learn a wee bit more about server tuning and content delivery to extend the scope and relevance of your advice.

You're quoting CloudFlare propaganda almost verbatim. And completely ignoring the fact that if a site is on a slow machine, the CDN does little to help speed. I've yet to see any CDN improve first byte time. That is because it cannot do that.

It is my opinion based on EXPERIENCE that you don't NEED a CDN. Notice the operative word, NEED.

You DO need to slim down a fat page, every time as a first step to fixing a slow website problem. Hopefully we can agree on that very simple, common sense basic.

I concentrate on the basic, simple things a typical site owner can do, first. At NO time have I told anyone not to take your advice as well. But cleaning up a fat site does much more than might meet the eye at first.

Good example: When a site owner complains to his shared hosting about his slow site, you well know the first thing they are going to do is find ways to blame HIM. But if the site is optimized, is svelte and is taking advantage of caching and compression, that's a BIG area of blame they try to use, gone. I've even seen on many occasions, hosts blaming use of a CDN for their slow machine!

I try to help people eliminate the simple stuff first. Works every time it is tried.

And the quote was William Safire, incidentally.