iOS GCD多线程

作者: 迎风起飞的猪 | 来源:发表于2018-12-04 18:14 被阅读6次

iOS多线程：『GCD』详尽总结
iOS多线程(一)-GCD
iOS多线程相关面试题
多线程之--NSOperation
iOS多线程之--NSThread
[iOS 多线程] iOS多线程-GCD
iOS 多线程
GCD练习
iOS开发多线程之GCD
iOS 多线程

直接上代码 --> 各种线程的创建方式

    /// 创建异步队列
    dispatch_queue_t async = dispatch_queue_create("async_queue", DISPATCH_QUEUE_CONCURRENT);
    /// 创建同步队列
    dispatch_queue_t sync = dispatch_queue_create("sync_queue", DISPATCH_QUEUE_SERIAL);
    
    
    /// 创建主队列
    dispatch_queue_t main_queue = dispatch_get_main_queue();
    
    /// 全局并发队列
    dispatch_queue_t global_queue = dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0);
    
    /// 同步
    dispatch_sync(global_queue, ^{
        
    });
    
    /// 异步
    dispatch_async(global_queue, ^{
        
    });

线程创建的6中方式

第一种 --> 同步并发(从上往下依次执行，没有开启新线程) 在当前线程中执行任务，不会开启新线程，执行完一个任务，再执行下一个任务
| 执行结果 --> 添加至主线程执行先执行begin最后执行end，依次执行

- (void)syncConcurrentThread
{
    NSLog(@"同步并发---begin %@",[NSThread currentThread]);
    dispatch_queue_t sync = dispatch_queue_create("syncConcurrent", DISPATCH_QUEUE_CONCURRENT);
    dispatch_sync(sync, ^{
        for (int i = 0; i < 3; i++) {
            NSLog(@"syncConcurrent = 1--%@",[NSThread currentThread]);
        }
    });
    dispatch_sync(sync, ^{
        for (int i = 0; i < 3; i++) {
            NSLog(@"syncConcurrent = 2--%@",[NSThread currentThread]);
        }
    });
    dispatch_sync(sync, ^{
        for (int i = 0; i < 3; i++) {
            NSLog(@"syncConcurrent = 3--%@",[NSThread currentThread]);
        }
    });
    NSLog(@"同步并发---end %@",[NSThread currentThread]);

}
执行结果：
同步并发---begin <NSThread: 0x600000566940>{number = 1, name = main}
syncConcurrent = 1--<NSThread: 0x600000566940>{number = 1, name = main}
syncConcurrent = 1--<NSThread: 0x600000566940>{number = 1, name = main}
syncConcurrent = 1--<NSThread: 0x600000566940>{number = 1, name = main}
syncConcurrent = 2--<NSThread: 0x600000566940>{number = 1, name = main}
syncConcurrent = 2--<NSThread: 0x600000566940>{number = 1, name = main}
syncConcurrent = 2--<NSThread: 0x600000566940>{number = 1, name = main}
syncConcurrent = 3--<NSThread: 0x600000566940>{number = 1, name = main}
syncConcurrent = 3--<NSThread: 0x600000566940>{number = 1, name = main}
syncConcurrent = 3--<NSThread: 0x600000566940>{number = 1, name = main}
同步并发---end <NSThread: 0x600000566940>{number = 1, name = main}

第二种 --> 异步并发(开启多个新线程，任务随机接近同时执行) 可以开启多个线程，任务同时随机执行
| 执行结果 --> 先执行主线程代码(begin，end)，在执行子线程代码，并随机执行

- (void)asyncConcurrentThread
{
    NSLog(@"异步并发---begin %@",[NSThread currentThread]);

    dispatch_queue_t sync = dispatch_queue_create("syncConcurrent", DISPATCH_QUEUE_CONCURRENT);
    dispatch_async(sync, ^{
        for (int i = 0; i < 3; i++) {
            NSLog(@"asyncConcurrent = 1--%@",[NSThread currentThread]);
        }
    });
    dispatch_async(sync, ^{
        for (int i = 0; i < 3; i++) {
            NSLog(@"asyncConcurrent = 2--%@",[NSThread currentThread]);
        }
    });
    dispatch_async(sync, ^{
        for (int i = 0; i < 3; i++) {
            NSLog(@"asyncConcurrent = 3--%@",[NSThread currentThread]);
        }
    });
    NSLog(@"异步并发---end %@",[NSThread currentThread]);

}
执行结果：
异步并发---begin <NSThread: 0x600000566940>{number = 1, name = main}
异步并发---end <NSThread: 0x600000566940>{number = 1, name = main}
asyncConcurrent = 1--<NSThread: 0x600000538980>{number = 3, name = (null)}
asyncConcurrent = 3--<NSThread: 0x600000538880>{number = 4, name = (null)}
asyncConcurrent = 2--<NSThread: 0x60000050ad40>{number = 5, name = (null)}
asyncConcurrent = 1--<NSThread: 0x600000538980>{number = 3, name = (null)}
asyncConcurrent = 3--<NSThread: 0x600000538880>{number = 4, name = (null)}
asyncConcurrent = 2--<NSThread: 0x60000050ad40>{number = 5, name = (null)}
asyncConcurrent = 1--<NSThread: 0x600000538980>{number = 3, name = (null)}
asyncConcurrent = 3--<NSThread: 0x600000538880>{number = 4, name = (null)}
asyncConcurrent = 2--<NSThread: 0x60000050ad40>{number = 5, name = (null)}

第三种 --> 同步串行 (任务依次执行，没有开启新线程) 不会开启新线程，在当前线程执行任务。任务是串行的，执行完一个任务，再执行下一个任务
| 执行结果 --> 先执行主线程的代码(begin,end)，在加入主线程依次执行

- (void)syncSerialThread
{
    NSLog(@"同步串行---begin %@",[NSThread currentThread]);

    dispatch_queue_t sync = dispatch_queue_create("syncConcurrent", DISPATCH_QUEUE_SERIAL);
    dispatch_sync(sync, ^{
        for (int i = 0; i < 3; i++) {
            NSLog(@"syncSerial = 1--%@",[NSThread currentThread]);
        }
    });
    dispatch_sync(sync, ^{
        for (int i = 0; i < 3; i++) {
            NSLog(@"syncSerial = 2--%@",[NSThread currentThread]);
        }
    });
    dispatch_sync(sync, ^{
        for (int i = 0; i < 3; i++) {
            NSLog(@"syncSerial = 3--%@",[NSThread currentThread]);
        }
    });
    NSLog(@"同步串行---end %@",[NSThread currentThread]);

}
执行结果：
同步串行---begin <NSThread: 0x600000566940>{number = 1, name = main}
syncSerial = 1--<NSThread: 0x600000566940>{number = 1, name = main}
syncSerial = 1--<NSThread: 0x600000566940>{number = 1, name = main}
syncSerial = 1--<NSThread: 0x600000566940>{number = 1, name = main}
syncSerial = 2--<NSThread: 0x600000566940>{number = 1, name = main}
syncSerial = 2--<NSThread: 0x600000566940>{number = 1, name = main}
syncSerial = 2--<NSThread: 0x600000566940>{number = 1, name = main}
syncSerial = 3--<NSThread: 0x600000566940>{number = 1, name = main}
syncSerial = 3--<NSThread: 0x600000566940>{number = 1, name = main}
syncSerial = 3--<NSThread: 0x600000566940>{number = 1, name = main}
同步串行---end <NSThread: 0x600000566940>{number = 1, name = main}

第四种 --> 异步串行 (开启一个线程) 会开启新线程，但是因为任务是串行的，执行完一个任务，再执行下一个任务
| 执行结果 --> 先执行主线程(begin,end)，然后在新的线程依次执行任务

- (void)asyncSerialThread
{
    NSLog(@"异步串行---begin %@",[NSThread currentThread]);

    dispatch_queue_t sync = dispatch_queue_create("syncConcurrent", DISPATCH_QUEUE_SERIAL);
    dispatch_async(sync, ^{
        for (int i = 0; i < 3; i++) {
            NSLog(@"asyncSerial = 1--%@",[NSThread currentThread]);
        }
    });
    dispatch_async(sync, ^{
        for (int i = 0; i < 3; i++) {
            NSLog(@"asyncSerial = 2--%@",[NSThread currentThread]);
        }
    });
    dispatch_async(sync, ^{
        for (int i = 0; i < 3; i++) {
            NSLog(@"asyncSerial = 3--%@",[NSThread currentThread]);
        }
    });
    NSLog(@"异步串行---end %@",[NSThread currentThread]);

}
执行结果：
异步串行---begin <NSThread: 0x600000566940>{number = 1, name = main}
异步串行---end <NSThread: 0x600000566940>{number = 1, name = main}
asyncSerial = 1--<NSThread: 0x600000538880>{number = 4, name = (null)}
asyncSerial = 1--<NSThread: 0x600000538880>{number = 4, name = (null)}
asyncSerial = 1--<NSThread: 0x600000538880>{number = 4, name = (null)}
asyncSerial = 2--<NSThread: 0x600000538880>{number = 4, name = (null)}
asyncSerial = 2--<NSThread: 0x600000538880>{number = 4, name = (null)}
asyncSerial = 2--<NSThread: 0x600000538880>{number = 4, name = (null)}
asyncSerial = 3--<NSThread: 0x600000538880>{number = 4, name = (null)}
asyncSerial = 3--<NSThread: 0x600000538880>{number = 4, name = (null)}
asyncSerial = 3--<NSThread: 0x600000538880>{number = 4, name = (null)}

第五种 --> 同步执行 + 主队列在主线程调用(卡死) 在其他线程调用(不会卡死，不会开启新线程，依次执行)
| 执行结果 --> 在主队列执行(卡死) 在子线程中(依次执行)

- (void)syncMainThread
{
    NSLog(@"同步执行 + 主队列 ---begin %@",[NSThread currentThread]);

    dispatch_queue_t main_queue = dispatch_get_main_queue();
    dispatch_sync(main_queue, ^{
        for (int i = 0; i < 3; i++) {
            NSLog(@"syncMain = 1--%@",[NSThread currentThread]);
        }
    });
    dispatch_sync(main_queue, ^{
        for (int i = 0; i < 3; i++) {
            NSLog(@"syncMain = 2--%@",[NSThread currentThread]);
        }
    });
    dispatch_sync(main_queue, ^{
        for (int i = 0; i < 3; i++) {
            NSLog(@"syncMain = 3--%@",[NSThread currentThread]);
        }
    });
    
    
    NSLog(@"同步执行 + 主队列 ---end %@",[NSThread currentThread]);

}
执行结果：
---begin <NSThread: 0x6000011b6940>{number = 1, name = main}

第六种 --> 异步执行 + 主队列在主线程中依次执行
| 执行结果 --> 先执行主线(begin,end)，然后依次执行任务

- (void)asyncMainThread
{
    NSLog(@"异步执行 + 主队列 ---begin %@",[NSThread currentThread]);
    
    dispatch_queue_t main_queue = dispatch_get_main_queue();
    dispatch_async(main_queue, ^{
        for (int i = 0; i < 3; i++) {
            NSLog(@"asyncMain = 1--%@",[NSThread currentThread]);
        }
    });
    dispatch_async(main_queue, ^{
        for (int i = 0; i < 3; i++) {
            NSLog(@"asyncMain = 2--%@",[NSThread currentThread]);
        }
    });
    dispatch_async(main_queue, ^{
        for (int i = 0; i < 3; i++) {
            NSLog(@"asyncMain = 3--%@",[NSThread currentThread]);
        }
    });
    NSLog(@"异步执行 + 主队列 ---end %@",[NSThread currentThread]);
}
执行结果：
异步执行 + 主队列 ---begin <NSThread: 0x6000018f6980>{number = 1, name = main}
异步执行 + 主队列 ---end <NSThread: 0x6000018f6980>{number = 1, name = main}
asyncMain = 1--<NSThread: 0x6000018f6980>{number = 1, name = main}
asyncMain = 1--<NSThread: 0x6000018f6980>{number = 1, name = main}
asyncMain = 1--<NSThread: 0x6000018f6980>{number = 1, name = main}
asyncMain = 2--<NSThread: 0x6000018f6980>{number = 1, name = main}
asyncMain = 2--<NSThread: 0x6000018f6980>{number = 1, name = main}
asyncMain = 2--<NSThread: 0x6000018f6980>{number = 1, name = main}
asyncMain = 3--<NSThread: 0x6000018f6980>{number = 1, name = main}
asyncMain = 3--<NSThread: 0x6000018f6980>{number = 1, name = main}
asyncMain = 3--<NSThread: 0x6000018f6980>{number = 1, name = main}

iOS多线程：『GCD』详尽总结
iOS多线程：『GCD』详尽总结 iOS多线程：『GCD』详尽总结
iOS多线程(一)-GCD
iOS多线程-GCD
iOS多线程相关面试题
iOS多线程demo iOS多线程之--NSThread iOS多线程之--GCD详解 iOS多线程之--NSOp...
多线程之--NSOperation
iOS多线程demo iOS多线程之--NSThread iOS多线程之--GCD详解 iOS多线程之--NSOp...
iOS多线程之--NSThread
iOS多线程demo iOS多线程之--NSThread iOS多线程之--GCD详解 iOS多线程之--NSOp...
[iOS 多线程] iOS多线程-GCD
iOS多线程-GCD GCD的简介 GCD，全称为 Grand Central Dispatch ，是iOS用来管...
iOS 多线程
iOS 多线程有几种方式 GCD NSOpeartion NSThread phread 多线程 GCD disp...
GCD练习
GCD练习 ios 多线程 GCD ： ios 多线程全剧队列，异步执行线程间通信信号量文件锁单利模式 ...
iOS开发多线程之GCD
iOS开发多线程之GCDiOS开发之GCD同步任务加强iOS开发之GCD串行队列iOS开发之GCD并发队列 GCD...
iOS 多线程
参考链接 iOS多线程iOS 多线程：『GCD』详尽总结iOS简单优雅的实现复杂情况下的串行需求(各种锁、GCD ...