22 Dec: so, you’ve got your site looking nice. But what happens when lots of people come and look at it? The truth is, most of the time nobody really knows, and the accurate answer is ‘it depends’. But if your site falls over easily or becomes really slow under moderate traffic, The Man will ask Why. And ‘it depends’ doesn’t sound so clever then.
LoadImpact is a handy little service to help you see what happens to response time when your site is subjected to simulated load of 50, 100 or more concurrent users. It’s just a guess, but the charts it shows you may give you some clues as to whether your site can cope with the scale, or whether you need to take more radical approaches to optimising or offloading some of the content to caches or content delivery networks such as Amazon’s CloudFront.
When you’re trying to work out what’s causing your pages to load slowly, there are some great little utilities to help you:
- Google Page Speed is a page speed analysis utility you can run yourself, or use via the excellent WebPageTest hosted service to run reports such as the one above, complete with an optimisation checklist and visualisation of which elements of your site are taking the time to load.
- Yahoo’s YSlow does a similar job, and comes as a handy Firefox add-on you can add to the indispensable Firebug browser utility every webby should have installed
In terms of monitoring, I like the paid-for service Pingdom, which alerts you when your sites become unresponsive and also records their average response time from different locations around the world. It’s a nice visual way to track how your site responsiveness changes under different conditions.