Our test agents run on AWS EC2 c4.large and c5.large instances which gives you plenty of CPU horsepower and are a good approximation for everyday desktop browsers.
But mobile devices are generally much slower than desktop, especially in developing countries where the next billion people will come online. So for our emulated mobile devices we throttle the CPU to better approximate the CPU available on actual devices.
Default CPU throttle
Higher values are slower. A CPU throttle of 2 means half the CPU.
Apple iPad (1.8)
Apple iPhone 5 (3.0)
Apple iPhone 6 (2.6)
Apple iPhone 7 (1.2)
Apple iPhone 8 (0.6)
Apple iPhone X (0.6)
Google Nexus 6 (2.9)
Google Nexus 7 (3.1)
Google Nexus 10 (3.0)
Google Pixel (2.4)
Google Pixel 2 (2.2)
Samsung Galaxy S III (3.2)
Samsung Galaxy S4 (3.1)
Samsung Galaxy S7 (2.3)
Samsung Galaxy S8 (2.2)
The newer AWS regions in France, Sweden and Hong Kong use the c5.large instance size which has a CPU that's around 20-30% faster than c4.large.
Set your own CPU throttle
If you want to change your CPU throttle or emulate any other older slower devices you can create a custom browser in your Settings.
1. Go to your Settings page and hit the green 'Edit Browsers' button.
2. Scroll down to the 'Custom Browser Profiles' section and click the link to add a custom profile.
3. The 'Add a Custom Browser' page gives you a bunch of customization options, including 'Throttle CPU'. In the example below, we've created a 2X CPU slowdown for Safari over 3G. We've named this profile 'Safari 3G throttled'.
4. When you've created your custom browser profile, hit the green 'Add' button. This will take you back to your main Settings page, where you'll see your new custom profile grouped with your other browsers. This browser profile is now available for you to use in your Sites settings.