方式4 使用phtread
- (void)pthreadDemo {
_testLock = [[TestLock alloc] init];
__block pthread_mutex_t mutex;
pthread_mutex_init(&mutex, NULL);
//线程1
dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), ^{
pthread_mutex_lock(&mutex);
[_testLock method1];
sleep(5);
pthread_mutex_unlock(&mutex);
});
//线程2
dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), ^{
sleep(1);
pthread_mutex_lock(&mutex);
[_testLock method2];
pthread_mutex_unlock(&mutex);
});
}
pthread_mutex_t定义在pthread.h，所以记得#include。
3 性能对比
这里简单写一个小程序来进行四种方式的性能对比，这里再固定次数内进行了加锁解锁，然后输出用时，结果如下（测试1、2执行次数不一样：测试1 < 测试2）：
测试1
2016-11-05 15:27:52.595 LockDemo[4394:202297] NSLock times:0.871843
2016-11-05 15:27:56.335 LockDemo[4394:202297] synthorize times:3.738939
2016-11-05 15:27:56.691 LockDemo[4394:202297] gcd times:0.355344
2016-11-05 15:27:57.328 LockDemo[4394:202297] pthread times:0.636815
2016-11-05 15:27:57.559 LockDemo[4394:202297] OSSPinLock times:0.231013
2016-11-05 15:27:57.910 LockDemo[4394:202297] os_unfair_lock times:0.350615
测试2
2016-11-05 15:30:54.123 LockDemo[4454:205180] NSLock times:1.908103
2016-11-05 15:31:02.112 LockDemo[4454:205180] synthorize times:7.988547
2016-11-05 15:31:02.905 LockDemo[4454:205180] gcd times:0.792113
2016-11-05 15:31:04.372 LockDemo[4454:205180] pthread times:1.466987
2016-11-05 15:31:04.870 LockDemo[4454:205180] OSSPinLock times:0.497487
2016-11-05 15:31:05.637 LockDemo[4454:205180] os_unfair_lock times:0.767569
这里还测试了OSSPinLock(此类已经被os_unfair_lock所替代)。结果如下：
synthorize > NSLock > pthread > gcd > os_unfair_lock >OSSPinLock
这里：
synthorize内部会添加异常处理，所以耗时。
pthread_mutex底层API，处理能力不错。
gcd系统封装的C代码效果比pthread好。
4 总结
简单就介绍这么多。
以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持ASPKU。
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