一组线程锁的性能数据

今天群内Kevin分享了一组线程锁的性能数据，在这里分享一下：

NSLock: 3.157997 sec
NSLock+IMP Cache: 3.212774 sec
pthread_mutex: 1.524530 sec
OSSpinlock: 0.293235 sec
@synchronized: 3.483270 sec

代码 objc:

#define ITERATIONS (1024*1024*32)
 
 for(i=0;i<ITERATIONS;++i){
 //lock code
 }

具体代码如下

代码 objc:

#define ITERATIONS (1024*1024*32)
 
static unsigned long long disp=0, land=0;
 
int main()
{
    double then, now;
    unsigned int i, count;
    pthread_mutex_t mutex = PTHREAD_MUTEX_INITIALIZER;
    OSSpinLock spinlock = OS_SPINLOCK_INIT;
 
    NSAutoreleasePool *pool = [NSAutoreleasePool new];
 
    NSLock *lock = [NSLock new];
    then = CFAbsoluteTimeGetCurrent();
    for(i=0;i<ITERATIONS;++i){
        [lock lock];
        [lock unlock];
    }
    now = CFAbsoluteTimeGetCurrent();
    printf("NSLock: %f sec\n", now-then);
 
 
    then = CFAbsoluteTimeGetCurrent();
    IMP lockLock = [lock methodForSelector:@selector(lock)];
    IMP unlockLock = [lock methodForSelector:@selector(unlock)];
    for(i=0;i<ITERATIONS;++i){
        lockLock(lock,@selector(lock));
        unlockLock(lock,@selector(unlock));
    }
    now = CFAbsoluteTimeGetCurrent();
    printf("NSLock+IMP Cache: %f sec\n", now-then);
 
    then = CFAbsoluteTimeGetCurrent();
    for(i=0;i<ITERATIONS;++i){
        pthread_mutex_lock(&mutex);
        pthread_mutex_unlock(&mutex);
    }
    now = CFAbsoluteTimeGetCurrent();
    printf("pthread_mutex: %f sec\n", now-then);
 
    then = CFAbsoluteTimeGetCurrent();
    for(i=0;i<ITERATIONS;++i){
        OSSpinLockLock(&spinlock);
        OSSpinLockUnlock(&spinlock);
    }
    now = CFAbsoluteTimeGetCurrent();
    printf("OSSpinlock: %f sec\n", now-then);
 
    id obj = [NSObject new];
 
    then = CFAbsoluteTimeGetCurrent();
    for(i=0;i<ITERATIONS;++i){
        @synchronized(obj){
        }
    }
    now = CFAbsoluteTimeGetCurrent();
    printf("@synchronized: %f sec\n", now-then);
 
    [pool release];
    return 0;
}