Google is working on a fix for laggy tablet mode on Chrome OS devices including the Pixel Slate

Ben Schoon | Dec 31 2018 - 8:10 am PT

Chrome OS was originally a laptop platform, but slowly it’s being reworked for tablet form factors. However, as that goes on, there have been some hiccups. Most recently, many have noted the poor performance of tablet mode especially on Chrome OS products like the Pixel Slate, but it seems a fix for that lag is incoming.

If you tuned into any hands-on or review coverage of Google’s Pixel Slate, you’re likely familiar with the performance issues many have described. In tablet mode, Chrome OS has a lot of issues with lag. This is especially evident in the multitasking screen, and it seems that is the first thing Google is looking at to fix these problems.

ChromeUnboxed notes a recent bug tracker which reveals how Google plans to start fixing Chrome OS tablet mode lag in the multitasking screen. Somewhat hilariously, it seems a big reason for the poor frame rates in the animations on this screen actually comes down to how the OS renders the rounded corners on this screen.

Even on the Celeron model of the Pixel Slate, the one seeing the worst performance, Google notes that removing these rounded corners brings a “significant” jump in performance overall. So, simply put, the rendering tasks required for creating the rounded corners of apps and also the background blur is a big reason why the overview screen sees so much lag.

A lot of animation jank seems to be coming from the use of Mask Layers to create rounded corners. This combined with background blur adds a lot of additional steps in the paint/rendering pipeline. The performance (fps increase) and memory improvement (tiles [don’t] get discarded and we actually see the content) is quite significant on Nocturne Celeron when rounded corners are removed.

When will this be fixed? That’s unclear. The bug tracker notes that Google wants to find another method of implementing this look, so it’s highly unlikely that we’ll see the design just revert to basics at any point. Regardless, it’s great to see that Google has heard feedback and is actively working on fixing the problem.