Tasks, queues, functions
Time consuming under different conditions
Main thread & serial queue
Asynchronous threads & parallel queues
Synchronous threads & parallel queues
Synchronous thread & serial queue
Concurrent multitasking
Source code analysis
The home side column
Global concurrent queue
Custom queue
Synchronization function task execution
A deadlock
The singleton
Asynchronous function task execution
example
Barrier function
The execution order of the fence function is not added
Added execution order of fence function
Bottom layer of fence function
A semaphore
example
