Vector displacement maps can be applied using the Vector Map shader.
A noise attached to the displacement parameter of the Arnold Material's Output.
In the Arnold Properties attached to the geometry, changing the Subdivision Type to Catmull-Clark and increasing the iterations will improve the displacement quality. In the examples below the iterations have been increased from 0 (Off) to 4.
You must be careful when increasing the number of iterations. Each iteration quadruples the number of polygons and can lead to some very dense geometry.
The subdivision/displacement speed is mainly determined by the number of Subdivision Iterations.
More information can be found on the Subdivision Properties page.
The Height, Bounds Padding and Zero Value of the Displacement are controlled on a per object basis through the Arnold Properties assigned to the object. More information can be found on the Displacement (geometry) page.