目标是让react整体渲染过程有个优先级的排比，能够让整体渲染能够中断的，让cpu的性能提升，让动画渲染流畅。优先执行优先级高的任务 文件路径 ``` packages/react/src/React.js ``` ~~~ //100行左右 if (enableStableConcurrentModeAPIs) { React.ConcurrentMode = REACT_CONCURRENT_MODE_TYPE; React.Profiler = REACT_PROFILER_TYPE; React.unstable_ConcurrentMode = undefined; React.unstable_Profiler = undefined; } ~~~