Edit > Delete by Type > Non-Deformer History >
Delete Non-Deformer History lets you delete history nodes upstream or both upstream and downstream from your object’s deformations and then bake the remaining history. This is useful when you want to delete modeling operations from your object’s history or any other nodes that are slowing down your scene’s recalculation time. Delete Non-Deformer History can also improve your scene’s performance and reduce its file size.
Delete Non-Deformer History Options
Delete
Select from the following options:
Deletes only the history upstream from the selected object’s deformations.
This option maintains any modeling history downstream of skinning and it does not change the appearance of your object. For example, you may want to keep a Smooth polygons operation on a low resolution mesh to preserve the high resolution mesh that is generated by the smooth.