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# allocator

The allocator object that created the buffer.

```
var allocator: any MDLMeshBufferAllocator { get }
```

## Discussion

Certain operations on the MDLMesh object that owns this buffer—for example, generating new vertex attributes with methods such as [`addNormals(withAttributeNamed:creaseThreshold:)`](/documentation/ModelIO/MDLMesh/addNormals(withAttributeNamed:creaseThreshold:)), or changing the format and layout of vertex data by assigning a new value to the [`vertexDescriptor`](/documentation/ModelIO/MDLMesh/vertexDescriptor) property—may require reallocation of buffer memory. When you perform such operations, Model I/O  uses the same allocator that was used to create the buffer.

---

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