Database engine implementations sometimes work similar to this, being locality optimizing machines. Objects in memory can be moved and reorganized dynamically.

Database engine implementations sometimes work similar to this, being locality optimizing machines. Objects in memory can be moved and reorganized dynamically. Ensuring that references to those objects remain valid is not inexpensive because it requires indirection to dynamically resolve object locations and may require patching state referencing the object. The performance impact is only tolerable for database engines because the context and scope is sufficiently constrained such that clever software design elements can ensure that the cost is applied lazily and expensive effects are avoided except in rare cases. Even in database engines, thrashing your CPU cache is a common side effect of not getting the design right. I can't imagine trying to make this perform well for general purpose software.