init(label:qos:attributes:autoreleaseFrequency:target:)
Creates a new dispatch queue to which you can submit blocks.
Declaration
convenience init(label: String, qos: DispatchQoS = .unspecified, attributes: DispatchQueue.Attributes = [], autoreleaseFrequency: DispatchQueue.AutoreleaseFrequency = .inherit, target: DispatchQueue? = nil)Parameters
- label:
A string label to attach to the queue to uniquely identify it in debugging tools such as Instruments, sample, stackshots, and crash reports. Because applications, libraries, and frameworks can all create their own dispatch queues, a reverse-DNS naming style (
com.example.myqueue) is recommended. - qos:
The quality-of-service level to associate with the queue. This value determines the priority at which the system schedules tasks for execution. For a list of possible values, see Qosclass Swift.enum.
- attributes:
The attributes to associate with the queue. Include the concurrent attribute to create a dispatch queue that executes tasks concurrently. If you omit that attribute, the dispatch queue executes tasks serially.
- autoreleaseFrequency:
The frequency with which to autorelease objects created by the blocks that the queue schedules. For a list of possible values, see Autoreleasefrequency.
- target:
The target queue on which to execute blocks. Specify
DISPATCH_TARGET_QUEUE_DEFAULTif you want the system to provide a queue that is appropriate for the current object.