---
title: preferBackgroundProcessing
framework: vision
role: symbol
role_heading: Instance Property
path: vision/vnrequest/preferbackgroundprocessing
---

# preferBackgroundProcessing

A hint to minimize the resource burden of the request.

## Declaration

```swift
var preferBackgroundProcessing: Bool { get set }
```

## Discussion

Discussion If set to true, this property reduces the request’s memory footprint, processing footprint, and CPU/GPU contention at the potential cost of longer execution time. Setting this value can help ensure that Vision processing doesn’t block UI updates and other rendering on the main thread.

## See Also

### Configuring a Request

- [VNRequestCompletionHandler](vision/vnrequestcompletionhandler.md)
- [completionHandler](vision/vnrequest/completionhandler.md)
- [results](vision/vnrequest/results.md)
- [revision](vision/vnrequest/revision.md)
- [usesCPUOnly](vision/vnrequest/usescpuonly.md)