Dear Webpagetest Members,
I have a site : http://dalano.com/
Recently (about 2 weeks) my site is going to loaded very slow and it has been so slowly than before.
Here is the result for webpagetest.org :
You are watching that TTFB is very terrible .
I have IIS 7.5 and Windows Server 2008 R2 with aspx website.
What is your opinion about improving my page speed and solving my recent problem?
CSS at the top and loading BEFORE any JS.
Move your JS as much as you can to the bottom and defer where possible.
Fix 404 errors reported in the testā¦ they have a red highlight.
Specify image dimensions
Optimize images
Leverage browser caching
As far i understand moving JS to bottom without defering will not accomplish much. The browser will be anyway waiting until it gets all js from the page (even if itās at bottom) to start rendering.
This is something Iām still figuring out actually. I just out of common practice defer js at the bottom, so it should load after the page render finishes. If something breaks, I remove the defer.
The TTFB is all on the server side in the application code (the aspx). Unfortunately from the outside thereās not much we can tell about why it is slow. Usually the main cause is slow/lots of database queries or calls to external services but it could be any of a thousand things. APM products like NewRelic can help you quickly find server-side issues.
The css files should be merged together into no more than 2 or 3 and as avalanch mentioned, moving the js to the bottom if it wonāt break the page can really help. The key is that if the UI actually depends on the JS to draw it then it wonāt make a difference.
Browsers will paint before loading the JS at the bottom of the page if there is something to paint.
[quote]Page Speed currently only detects image dimensions that are specified via the image attributes. If you are specifying the dimensions via CSS, then you can safely ignore this recommendation.
Details from Google
When the browser lays out the page, it needs to be able to flow around replaceable elements such as images. It can begin to render a page even before images are downloaded, provided that it knows the dimensions to wrap non-replaceable elements around. If no dimensions are specified in the containing document, or if the dimensions specified donāt match those of the actual images, the browser will require a reflow and repaint once the images are downloaded. To prevent reflows, specify the width and height of all images, either in the HTML tag, or in CSS.[/quote]
For sites with little images, this shouldnāt matter. But for sites trying to place 50 plus different imagesā¦ then yeah, it would make a difference. Plus this can make a difference when ranking for āserve scaled imagesā.
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