# MTLAllocation A memory allocation from a Metal GPU device, such as a memory heap, texture, or data buffer. ``` protocol MTLAllocation : NSObjectProtocol ``` ## Overview Types that conform to [`MTLAllocation`](/documentation/Metal/MTLAllocation), including [`MTLBuffer`](/documentation/Metal/MTLBuffer), [`MTLTexture`](/documentation/Metal/MTLTexture), and [`MTLHeap`](/documentation/Metal/MTLHeap), have underlying memory. You make their memory *resident*, or GPU-accessible, by adding an allocation to an [`MTLResidencySet`](/documentation/Metal/MTLResidencySet) or calling the appropriate method of a command encoder. See [Simplifying GPU resource management with residency sets](/documentation/Metal/simplifying-gpu-resource-management-with-residency-sets) for more information. ## Topics ### Inspecting an allocation [`allocatedSize`](/documentation/Metal/MTLAllocation/allocatedSize) The amount of memory, in byes, a resource consumes, such as for a buffer, texture, or heap. --- Copyright © 2026 Apple Inc. All rights reserved. | [Terms of Use](https://www.apple.com/legal/internet-services/terms/site.html) | [Privacy Policy](https://www.apple.com/privacy/privacy-policy)