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# maxConcurrentOperationCount

The maximum number of queued operations that can run at the same time.

```
var maxConcurrentOperationCount: Int { get set }
```

## Discussion

The value in this property affects only the operations that the current queue has executing at the same time. Other operation queues can also execute their maximum number of operations in parallel.

Reducing the number of concurrent operations does not affect any operations that are currently executing. Specifying the value `NSOperationQueueDefaultMaxConcurrentOperationCount` (which is recommended) causes the system to set the maximum number of operations based on system conditions.

The default value of this property is [`defaultMaxConcurrentOperationCount`](/documentation/Foundation/OperationQueue/defaultMaxConcurrentOperationCount). You may monitor changes to the value of this property using [Key-value observing](https://developer.apple.com/library/archive/documentation/General/Conceptual/DevPedia-CocoaCore/KVO.html#//apple_ref/doc/uid/TP40008195-CH16). Configure an observer to monitor the [`maxConcurrentOperationCount`](/documentation/Foundation/OperationQueue/maxConcurrentOperationCount) key path of the operation queue.

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