Monitoring Site Speed
From Joomla! Documentation
The next problem that we commonly see is to do with site speed – the time it takes for your pages to load. There are a number of factors which affect the time it taks a page to load – not only to do with with page itself, but also the server it is hosted on and the location of the person visiting the site.
Analysing site performance
Firstly, it's a good idea to have a look at how the site is performing – there is a view in Google Analytics called Site Speed Page Timings which allows you to view this information over time. You can also run tests using Pingdom Tools – with servers located around the world to find out how your site is performing at this moment in time. Often this is useful to get a before and after comparison when enabling caching, compression and so forth to see what kind of difference is being seen in the load time.
Monitoring speed by geographical region
It may also be relevant to analyse the speed of your site by geographical region – when you are viewing the Site Speed Page Timings report, you can click on a tab at the top of the page to show the data on a map overlay. This shows you which countries are experiencing problems with site speed and can help you to put in place measures to improve this. You can see from this graph that there seemed to have been a bit of a problem with people visiting this site from Spain during the time period selected – if this continued to be a problem it would be important to investigate further – especially if that geographical region is important for your website.