---
title: refitScratchBufferSize
framework: metal
role: symbol
role_heading: Instance Property
path: metal/mtlaccelerationstructuresizes/refitscratchbuffersize
---

# refitScratchBufferSize

The amount of scratch memory, in bytes, the GPU device needs to refit the acceleration structure.

## Declaration

```swift
var refitScratchBufferSize: Int
```

## Discussion

Discussion This value can be zero, which indicates that refitting the acceleration structure doesn’t require a scratch buffer.

## See Also

### Retrieving the sizes

- [accelerationStructureSize](metal/mtlaccelerationstructuresizes/accelerationstructuresize.md)
- [buildScratchBufferSize](metal/mtlaccelerationstructuresizes/buildscratchbuffersize.md)