---
title: "copy(with:device:)"
framework: metalperformanceshaders
role: symbol
role_heading: Instance Method
path: "metalperformanceshaders/mpskernel/copy(with:device:)"
---

# copy(with:device:)

Makes a copy of this kernel object for a new device.

## Declaration

```swift
func copy(with zone: NSZone? = nil, device: (any MTLDevice)?) -> Self
```

## Parameters

- `zone`: The zone in which to allocate the kernel object.
- `device`: The Metal device for the new kernel object.

## Mentioned in

The MPSKernel Class

## Return Value

Return Value A copy of this kernel object.

## Discussion

Discussion The same kernel objects should not be used to encode separate kernel operations on multiple command buffers from multiple threads. Many kernels have mutable properties that might be changed by another thread while the kernel is being encoded. If you need to use a kernel from multiple threads, make a copy of it for each additional thread using copy(with:) or copy(with:device:). Note that the copy(with:) method makes a copy of the kernel object on the same device. This method fails if the device is not supported. Query the MPSSupportsMTLDevice(_:) function to determine whether the device is supported.

## See Also

### Methods

- [init(device:)](metalperformanceshaders/mpskernel/init(device:).md)