Native App Performance

By now you will have realized Windows on ARM performance is rather terrible if you need to emulate an x86 app. In most situations, the Snapdragon 835 can't match or even come close to the Celeron N3450, while the faster Core i7-7Y75 utterly embarrasses the Qualcomm SoC. These Intel CPUs have the advantage of running x86 code natively, and boy is that a significant advantage.

However there are some situations where you can and will be running native code on the ARM chip, so it's fair to benchmark that performance, too, and see how it stacks up to roughly the same apps running on Intel's x86 CPUs natively.

The most interesting of the tests here are the browser tests. Microsoft's Edge browser runs natively on ARM and x86 processors, while Google Chrome is x86-only, and needs to be emulated on ARM processors. Here we have a selection of devices running the Octane benchmark in both Chrome and Edge, and I've included the Google Pixel 2 XL smartphone in here as well just to see how it all stacks up to the Snapdragon 835 running well in a phone.

The results really highlight the difference between emulation and native code. While not a like-for-like as Edge and Chrome use different rendering engines, Chrome performance is terrible on the Envy x2 compared to Edge. In contrast, Chrome and Edge are roughly equivalent on the N3450, while Chrome is much faster on the Core i5-5200U. And yes, I'm using the old i5-5200U here as we know the latest Kaby Lake processors will destroy the Snapdragon 835.

The important thing to note here is the Envy x2 trades blows with the N3450 when looking at the Edge results, while the 5200U is just 37 percent faster. It's also good to see the Windows on ARM Edge results matching what we saw on the smartphone side, which suggests everything is working as expected. Switch Windows on ARM to running an emulated version of Chrome, and it gets annihilated by the Intel devices in this test.

In Basemark Web 3.0 it's a similar situation. Using Edge gives the Snapdragon 835 a handy advantage, allowing it to beat the N3450 and come closer to the i5-5200U. Using Chrome gives the Snapdragon 835 a decent disadvantage due to emulation.

Another UWP app I benchmarked was PDF Viewer Plus, one of the most popular PDF viewers in the Microsoft Store. Here, Windows on ARM was quite competitive, posting a loading time between the N3450 and Core i5-5200U, which is decent considering a lot of the other results.