There is a new Crosswalk option in the CLI 5.1.1 and CW15 build system that allows you to select one of two different "performance" modes for Crosswalk. Here's what you need to use, within your intelxdk.config.additions.xml file:
<!-- controls configuration of Crosswalk-Android "SurfaceView" or "TextureView" --><!-- see Sep 15 comments in https://crosswalk-project.org/jira/browse/XWALK-2233 --><!-- default is SurfaceView if >= CW15 and TextureView if <= CW14 --><!-- option can only be used with Intel XDK CLI5+ build systems --><!-- enable Crosswalk-Android TextureView by setting option to true --><preference name="CrosswalkAnimatable" value="false" />
Set to either "true" or "false" and test your app to see which provides the best performance. What is "best" will depend on the type of app, so there is no "right answer" when it comes to selecting this option, you need to experiment and see which is best for you.