Microsoft has a number of Office apps that are available on the web, like Word, PowerPoint, Excel, Outlook, and Teams. Even though they are being used in web browsers, that doesn't mean they are not complex apps.
In a blog post, the Microsoft Edge team says it has been working with the Office Performance team to help boost the overall performance of these web apps. The blog mentions that the Office team was looking into the PowerPoint web app. The blog states:
While doing so, they noticed significant CPU usage overhead while recording profiles in the Performance tool of Edge DevTools. In fact, in some instances, DevTools was seemingly responsible for saturating an engineer’s 10 core CPU while profiling.
The team used the Event Tracing for Windows (ETW) tool to figure out what was going on. It found that the CPU profiler in Edge's Chromium browser engine was "using a busy waiting approach which meant constantly running code even while waiting for the next event."
By using a more accurate sleep timing method, the team was able to reduce the CPU sampling overhead by 95% and decrease the total CPU consumption from Edge by 71% while profiling. Of course, this helped the PowerPoint team investigate and improve the load performance of their app, but this also means that everyone using the Performance tool in DevTools (in Edge or any Chromium browser) now has a much better experience.
The blog post offers more examples of how these DevTools performance tools have helped the Office Performance team "enable concrete performance improvements in production web experiences." The company stated:
At the center of all these new DevTools features and Microsoft product improvements, we’re working to leverage our close relationships with some of the industry’s most powerful web apps to ensure that developer tooling is up to the task.
It should be interesting to see if these Office web apps will continue to get performance books with these DevTools collaborations with the Edge team.