Precise tracing of IIS and/or SQL
I am experiencing a performance bottle-neck in this website: http://oceanosdecolor.es/ and I'm not able to find it. If you try, you'll see any page (for example, homepage) takes a long time to load.
The first time you execute a page, the site reloads to detect client device, but that's only the first time and then it keeps client device so it doesn't reload again.
I log traces of the execution to database but I don't get useful information as, according to the log, the execution of the whole homepage happens in the same 1 second, but I can see that the homepage takes more time to load.
The IIS log (when trying locally) doesn't help as this also gives information in seconds, not miliseconds, and again, it says everything happens in the same second, and anyway running locally is much faster than on the server.
So, I ask for help in any tool to monitor performance with more accuracy or any technique I could use.
I think your answer might not lie with IIS or SQL Server. According to the Developer Tools in Chrome, your actual page execution and sending out the HTML takes 400ms on first load from my location. The problem is you have a tangle of CSS files (many of which are not being found and causing extremely long delays). Also you have a lot of requests.
I would install Yahoo's YSlow for your favourite browser. This will give you a whole bunch of recommendations for what is running slow on your site from an end-user perspective.
To use the Developer Tools on Chrome: right click on your page, hit "Inspect Element" and then go to the "Network" tab and then hard-refresh your browser (shift-F5).
A few of the problems I see are: commun.css (2.5 seconds and failed), layout.css (400ms and failed), jquery-ui-1.8.10.custom.min.js (800ms and failed).
Find the reason for these failing and fix it and I'm sure your site will load faster. Also try use CSS image sprites wherever possible to cut down on the number of requests.