iOS 多线程的简单理解执行方式 + 执行对列 的组合

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通过对前面两偏线程理解的总结,自己对线程的理解也逐渐加深,梳理的清晰起来……

 

通常在使用线程 的时候,都是要用到 执行对列,执行方式,执行任务,

现在开始新一轮的深入

 

3. 1. 1  同步 + 串行

- (void)syncSerialQueue{
    
    dispatch_queue_t queue = dispatch_queue_create("test", DISPATCH_QUEUE_SERIAL);

    NSLog(@" 同步 + 串行 start:::%@ ",[NSThread currentThread]);

    dispatch_sync(queue, ^{ // 添加任务 1
        for (int i = 0; i < 3; i++) {
            NSLog(@"同步 + 串行   index %d ::: %@",i,[NSThread currentThread]);
        }
    });
    
    dispatch_sync(queue, ^{  // 添加任务 2
        for (int i = 10; i < 13; i++) {
            NSLog(@"同步 + 串行   index %d ::: %@",i,[NSThread currentThread]);
        }
    });
    NSLog(@"同步 + 串行  end :::%@",[NSThread currentThread]);
}

 执行结果:::

2017-12-21 09:10:16.725075+0800 DeadThread[10455:3327379]  同步 + 串行 start:::<NSThread: 0x60800006b4c0>{number = 1, name = main} 
2017-12-21 09:10:16.725222+0800 DeadThread[10455:3327379] 同步 + 串行   index 0 ::: <NSThread: 0x60800006b4c0>{number = 1, name = main}
2017-12-21 09:10:16.725339+0800 DeadThread[10455:3327379] 同步 + 串行   index 1 ::: <NSThread: 0x60800006b4c0>{number = 1, name = main}
2017-12-21 09:10:16.725530+0800 DeadThread[10455:3327379] 同步 + 串行   index 2 ::: <NSThread: 0x60800006b4c0>{number = 1, name = main}
2017-12-21 09:10:16.725615+0800 DeadThread[10455:3327379] 同步 + 串行   index 10 ::: <NSThread: 0x60800006b4c0>{number = 1, name = main}
2017-12-21 09:10:16.725765+0800 DeadThread[10455:3327379] 同步 + 串行   index 11 ::: <NSThread: 0x60800006b4c0>{number = 1, name = main}
2017-12-21 09:10:16.725821+0800 DeadThread[10455:3327379] 同步 + 串行   index 12 ::: <NSThread: 0x60800006b4c0>{number = 1, name = main}
2017-12-21 09:10:16.725870+0800 DeadThread[10455:3327379] 同步 + 串行  end :::<NSThread: 0x60800006b4c0>{number = 1, name = main}

 总结结果:::

1.   同步 : 在当前线程执行,不开启新的线程,任务顺序执行

2.  串行 :添加的任务 顺序排列,顺序执行

图示::::

 

3.1.2  同步 +  并行

- (void)syncConcurrentQueue{
    
    dispatch_queue_t queue = dispatch_queue_create("test", DISPATCH_QUEUE_CONCURRENT);
    
    NSLog(@"同步 + 并行 start:::%@ ",[NSThread currentThread]);
    
    dispatch_sync(queue, ^{
        for (int i = 0; i < 3; i++) {
            NSLog(@"同步 + 并行   index %d ::: %@",i,[NSThread currentThread]);
        }
    });
    
    dispatch_sync(queue, ^{
        for (int i = 10; i < 13; i++) {
            NSLog(@"同步 + 并行  index %d ::: %@",i,[NSThread currentThread]);
        }
    });
    
    NSLog(@"同步 + 并行  end :::%@",[NSThread currentThread]);
}

执行结果:::

2017-12-21 09:37:05.376797+0800 DeadThread[10595:3430843] 同步 + 并行 start:::<NSThread: 0x6040000759c0>{number = 1, name = main} 
2017-12-21 09:37:05.376915+0800 DeadThread[10595:3430843] 同步 + 并行   index 0 ::: <NSThread: 0x6040000759c0>{number = 1, name = main}
2017-12-21 09:37:05.377000+0800 DeadThread[10595:3430843] 同步 + 并行   index 1 ::: <NSThread: 0x6040000759c0>{number = 1, name = main}
2017-12-21 09:37:05.377101+0800 DeadThread[10595:3430843] 同步 + 并行   index 2 ::: <NSThread: 0x6040000759c0>{number = 1, name = main}
2017-12-21 09:37:05.377262+0800 DeadThread[10595:3430843] 同步 + 并行  index 10 ::: <NSThread: 0x6040000759c0>{number = 1, name = main}
2017-12-21 09:37:05.377372+0800 DeadThread[10595:3430843] 同步 + 并行  index 11 ::: <NSThread: 0x6040000759c0>{number = 1, name = main}
2017-12-21 09:37:05.377440+0800 DeadThread[10595:3430843] 同步 + 并行  index 12 ::: <NSThread: 0x6040000759c0>{number = 1, name = main}
2017-12-21 09:37:05.377514+0800 DeadThread[10595:3430843] 同步 + 并行  end :::<NSThread: 0x6040000759c0>{number = 1, name = main}

 总结结果:::

1.   同步 : 在当前线程执行,不开启新的线程,任务顺序执行

2.  并行 :添加的任务 不是顺序排列

图示::::

 

3.2.1 异步 + 串行

- (void)asyncSerialQueue{
    
    dispatch_queue_t queue = dispatch_queue_create("test", DISPATCH_QUEUE_SERIAL);
    
    NSLog(@"异步 + 串行 start:::%@ ",[NSThread currentThread]);
    
    dispatch_async(queue, ^{
        for (int i = 0; i < 3; i++) {
            NSLog(@"异步 + 串行   index %d ::: %@",i,[NSThread currentThread]);
        }
    });
    
    dispatch_async(queue, ^{
        for (int i = 10; i < 13; i++) {
            NSLog(@"异步 + 串行   index %d ::: %@",i,[NSThread currentThread]);
        }
    });
    
    NSLog(@"异步 + 串行  end :::%@",[NSThread currentThread]);
}

 执行结果::::

2017-12-21 09:43:04.903888+0800 DeadThread[10647:3468013] 异步 + 串行 start:::<NSThread: 0x60c0000654c0>{number = 1, name = main} 
2017-12-21 09:43:04.904032+0800 DeadThread[10647:3468013] 异步 + 串行  end :::<NSThread: 0x60c0000654c0>{number = 1, name = main}
2017-12-21 09:43:04.904056+0800 DeadThread[10647:3468266] 异步 + 串行   index 0 ::: <NSThread: 0x604000074580>{number = 3, name = (null)}
2017-12-21 09:43:04.904127+0800 DeadThread[10647:3468266] 异步 + 串行   index 1 ::: <NSThread: 0x604000074580>{number = 3, name = (null)}
2017-12-21 09:43:04.904180+0800 DeadThread[10647:3468266] 异步 + 串行   index 2 ::: <NSThread: 0x604000074580>{number = 3, name = (null)}
2017-12-21 09:43:04.904370+0800 DeadThread[10647:3468266] 异步 + 串行   index 10 ::: <NSThread: 0x604000074580>{number = 3, name = (null)}
2017-12-21 09:43:04.904534+0800 DeadThread[10647:3468266] 异步 + 串行   index 11 ::: <NSThread: 0x604000074580>{number = 3, name = (null)}
2017-12-21 09:43:04.904603+0800 DeadThread[10647:3468266] 异步 + 串行   index 12 ::: <NSThread: 0x604000074580>{number = 3, name = (null)}

 总结结果:::

1.异步: 开启新的线程,不影响当前线程;

2.串行: 添加 任务 顺序排列,顺序执行

 

3.2.2  异步 + 并行

- (void)asyncConcurrentQueue{
    
    dispatch_queue_t queue = dispatch_queue_create("test", DISPATCH_QUEUE_CONCURRENT);
    
    NSLog(@"异步 + 并行 start:::%@ ",[NSThread currentThread]);
    
    dispatch_async(queue, ^{
        for (int i = 0; i < 3; i++) {
            NSLog(@"异步 + 并行   index %d ::: %@",i,[NSThread currentThread]);
        }
    });
    
    dispatch_async(queue, ^{
        for (int i = 10; i < 13; i++) {
            NSLog(@"异步 + 并行  index %d ::: %@",i,[NSThread currentThread]);
        }
    });
    
    NSLog(@"同步 + 并行  end :::%@",[NSThread currentThread]);
}

 执行结果:::

2017-12-21 09:50:40.207852+0800 DeadThread[10727:3517966] 异步 + 并行 start:::<NSThread: 0x60c00006d880>{number = 1, name = main} 
2017-12-21 09:50:40.208038+0800 DeadThread[10727:3517966] 同步 + 并行  end :::<NSThread: 0x60c00006d880>{number = 1, name = main}
2017-12-21 09:50:40.208045+0800 DeadThread[10727:3518055] 异步 + 并行  index 10 ::: <NSThread: 0x60400006f3c0>{number = 3, name = (null)}
2017-12-21 09:50:40.208066+0800 DeadThread[10727:3518052] 异步 + 并行   index 0 ::: <NSThread: 0x600000075700>{number = 4, name = (null)}
2017-12-21 09:50:40.208139+0800 DeadThread[10727:3518055] 异步 + 并行  index 11 ::: <NSThread: 0x60400006f3c0>{number = 3, name = (null)}
2017-12-21 09:50:40.208197+0800 DeadThread[10727:3518052] 异步 + 并行   index 1 ::: <NSThread: 0x600000075700>{number = 4, name = (null)}
2017-12-21 09:50:40.208327+0800 DeadThread[10727:3518055] 异步 + 并行  index 12 ::: <NSThread: 0x60400006f3c0>{number = 3, name = (null)}
2017-12-21 09:50:40.208361+0800 DeadThread[10727:3518052] 异步 + 并行   index 2 ::: <NSThread: 0x600000075700>{number = 4, name = (null)}

 总结结果::::

1.异步:开启线程能力;

2.并行:任务队列不顺序排列,同时执行;

3.开启线程的数量:取决于添加任务的数量

图示:::

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