GCDにおけるキューとタスクネストの組合せテスト
9932 ワード
以下を参照してください.
GCDは人を惑わせやすいいくつかの小さな問題です
GCDにおけるキューとタスクネストの組合せ分析
スレッドセキュリティArray
結果:
結果:エラー
結果:
結果:エラー
結果:予測不可能、無秩序
結果:insideからoutside
結果:予測不可能、無秩序
結果:insideからoutside
barrierの役割は、barrierの前のタスクを実行してからbarrierの後のタスクを実行することです.
GCDは人を惑わせやすいいくつかの小さな問題です
GCDにおけるキューとタスクネストの組合せ分析
スレッドセキュリティArray
dispatch_async、dispatch_sync、dispatch_barrier_async、dispatch_barrier_sync
PS: ，
1.シリアルキュー（SERIAL）
1）非同期ネスト非同期
-(void)serialAsyncAsync{
dispatch_queue_t serialQueue = dispatch_queue_create("com.chenl.gcddemo", DISPATCH_QUEUE_SERIAL);
dispatch_async(serialQueue, ^{
NSLog(@"outside -- %@",[NSThread currentThread]);
dispatch_async(serialQueue, ^{
NSLog(@"inside -- %@",[NSThread currentThread]);
for (int i=0; i<10; i++) {
NSLog(@"inside -- %@",@(i));
}
});
for (int i=0; i<10; i++) {
NSLog(@"outside -- %@",@(i));
}
NSLog(@"outside end -- %@",[NSThread currentThread]);
});
}
結果:
2019-04-08 11:35:46.614228+0800 GCDDemo[4091:214368] outside -- {number = 3, name = (null)}
2019-04-08 11:35:46.614478+0800 GCDDemo[4091:214368] outside -- 0
2019-04-08 11:35:46.614588+0800 GCDDemo[4091:214368] outside -- 1
...
2019-04-08 11:35:46.615971+0800 GCDDemo[4091:214368] outside -- 9
2019-04-08 11:35:46.616262+0800 GCDDemo[4091:214368] outside end -- {number = 3, name = (null)}
2019-04-08 11:35:46.616494+0800 GCDDemo[4091:214368] inside -- {number = 3, name = (null)}
2019-04-08 11:35:46.616695+0800 GCDDemo[4091:214368] inside -- 0
2019-04-08 11:35:46.617105+0800 GCDDemo[4091:214368] inside -- 1
...
2019-04-08 11:35:46.621248+0800 GCDDemo[4091:214368] inside -- 9
2）非同期ネスト同期（ERROR）
-(void)serialAsyncSync{
dispatch_queue_t serialQueue = dispatch_queue_create("com.chenl.gcddemo", DISPATCH_QUEUE_SERIAL);
dispatch_async(serialQueue, ^{
NSLog(@"outside -- %@",[NSThread currentThread]);
dispatch_sync(serialQueue, ^{
NSLog(@"inside -- %@",[NSThread currentThread]);
for (int i=0; i<10; i++) {
NSLog(@"inside -- %@",@(i));
}
});
for (int i=0; i<10; i++) {
NSLog(@"outside -- %@",@(i));
}
NSLog(@"outside end -- %@",[NSThread currentThread]);
});
}
結果:エラー
3）同期ネスト非同期
-(void)serialSyncAsync{
dispatch_queue_t serialQueue = dispatch_queue_create("com.chenl.gcddemo", DISPATCH_QUEUE_SERIAL);
dispatch_sync(serialQueue, ^{
NSLog(@"outside -- %@",[NSThread currentThread]);
dispatch_async(serialQueue, ^{
NSLog(@"inside -- %@",[NSThread currentThread]);
for (int i=0; i<10; i++) {
NSLog(@"inside -- %@",@(i));
}
});
for (int i=0; i<10; i++) {
NSLog(@"outside -- %@",@(i));
}
NSLog(@"outside end -- %@",[NSThread currentThread]);
});
}
結果:
2019-04-08 11:38:28.763058+0800 GCDDemo[4142:222924] outside -- {number = 1, name = main}
2019-04-08 11:38:28.763196+0800 GCDDemo[4142:222924] outside -- 0
2019-04-08 11:38:28.763270+0800 GCDDemo[4142:222924] outside -- 1
...
2019-04-08 11:38:28.763843+0800 GCDDemo[4142:222924] outside -- 9
2019-04-08 11:38:28.763984+0800 GCDDemo[4142:222924] outside end -- {number = 1, name = main}
2019-04-08 11:38:28.764156+0800 GCDDemo[4142:223088] inside -- {number = 3, name = (null)}
2019-04-08 11:38:28.764441+0800 GCDDemo[4142:223088] inside -- 0
2019-04-08 11:38:28.764633+0800 GCDDemo[4142:223088] inside -- 1
...
2019-04-08 11:38:28.769840+0800 GCDDemo[4142:223088] inside -- 9
4）ネスト同期の同期
-(void)serialSyncSync{
dispatch_queue_t serialQueue = dispatch_queue_create("com.chenl.gcddemo", DISPATCH_QUEUE_SERIAL);
dispatch_sync(serialQueue, ^{
NSLog(@"outside -- %@",[NSThread currentThread]);
dispatch_sync(serialQueue, ^{
NSLog(@"inside -- %@",[NSThread currentThread]);
for (int i=0; i<10; i++) {
NSLog(@"inside -- %@",@(i));
}
});
for (int i=0; i<10; i++) {
NSLog(@"outside -- %@",@(i));
}
NSLog(@"outside end -- %@",[NSThread currentThread]);
});
}
結果:エラー
結論:
， ， ； 。
2.パラレルキュー（CONCURRENT）
1）非同期ネスト非同期
-(void)currentAsyncAsync{
dispatch_queue_t currentQueue = dispatch_queue_create("com.chenl.gcddemo", DISPATCH_QUEUE_CONCURRENT);
dispatch_async(currentQueue, ^{
NSLog(@"outside -- %@",[NSThread currentThread]);
dispatch_async(currentQueue, ^{
NSLog(@"inside -- %@",[NSThread currentThread]);
for (int i=0; i<10; i++) {
NSLog(@"inside -- %@",@(i));
}
});
for (int i=0; i<10; i++) {
NSLog(@"outside -- %@",@(i));
}
NSLog(@"outside end -- %@",[NSThread currentThread]);
});
}
結果:予測不可能、無秩序
2）非同期ネスト同期
-(void)currentAsyncSync{
dispatch_queue_t currentQueue = dispatch_queue_create("com.chenl.gcddemo", DISPATCH_QUEUE_CONCURRENT);
dispatch_async(currentQueue, ^{
NSLog(@"outside -- %@",[NSThread currentThread]);
dispatch_sync(currentQueue, ^{
NSLog(@"inside -- %@",[NSThread currentThread]);
dispatch_sync(currentQueue, ^{
NSLog(@"inside inside");
for (int i=0; i<10; i++) {
NSLog(@"inside inside -- %@",@(i));
}
});
for (int i=0; i<10; i++) {
NSLog(@"inside -- %@",@(i));
}
});
for (int i=0; i<10; i++) {
NSLog(@"outside -- %@",@(i));
}
NSLog(@"outside end -- %@",[NSThread currentThread]);
});
}
結果:insideからoutside
2019-04-08 15:22:32.998533+0800 GCDDemo[13049:500501] outside -- {number = 3, name = (null)}
2019-04-08 15:22:32.998799+0800 GCDDemo[13049:500501] inside -- {number = 3, name = (null)}
2019-04-08 15:22:32.998881+0800 GCDDemo[13049:500501] inside inside
2019-04-08 15:22:32.998989+0800 GCDDemo[13049:500501] inside inside -- 0
2019-04-08 15:22:32.999955+0800 GCDDemo[13049:500501] inside inside -- 1
...
2019-04-08 15:22:33.001734+0800 GCDDemo[13049:500501] inside inside -- 9
2019-04-08 15:22:33.001803+0800 GCDDemo[13049:500501] inside -- 0
2019-04-08 15:22:33.002653+0800 GCDDemo[13049:500501] inside -- 1
...
2019-04-08 15:22:33.008001+0800 GCDDemo[13049:500501] inside -- 9
2019-04-08 15:22:33.008077+0800 GCDDemo[13049:500501] outside -- 0
2019-04-08 15:22:33.008151+0800 GCDDemo[13049:500501] outside -- 1
...
2019-04-08 15:22:33.009867+0800 GCDDemo[13049:500501] outside -- 9
2019-04-08 15:22:33.010082+0800 GCDDemo[13049:500501] outside end -- {number = 3, name = (null)}
3）同期ネスト非同期
-(void)currentSyncAsync{
dispatch_queue_t currentQueue = dispatch_queue_create("com.chenl.gcddemo", DISPATCH_QUEUE_CONCURRENT);
dispatch_sync(currentQueue, ^{
NSLog(@"outside -- %@",[NSThread currentThread]);
dispatch_async(currentQueue, ^{
NSLog(@"inside -- %@",[NSThread currentThread]);
for (int i=0; i<10; i++) {
NSLog(@"inside -- %@",@(i));
}
});
for (int i=0; i<10; i++) {
NSLog(@"outside -- %@",@(i));
}
NSLog(@"outside end -- %@",[NSThread currentThread]);
});
}
結果:予測不可能、無秩序
4）ネスト同期の同期
-(void)currentSyncSync{
dispatch_queue_t currentQueue = dispatch_queue_create("com.chenl.gcddemo", DISPATCH_QUEUE_CONCURRENT);
dispatch_sync(currentQueue, ^{
NSLog(@"outside -- %@",[NSThread currentThread]);
dispatch_sync(currentQueue, ^{
NSLog(@"inside -- %@",[NSThread currentThread]);
for (int i=0; i<10; i++) {
NSLog(@"inside -- %@",@(i));
}
});
for (int i=0; i<10; i++) {
NSLog(@"outside -- %@",@(i));
}
NSLog(@"outside end -- %@",[NSThread currentThread]);
});
}
結果:insideからoutside
2019-04-08 15:24:15.335330+0800 GCDDemo[13082:506871] outside -- {number = 1, name = main}
2019-04-08 15:24:15.335629+0800 GCDDemo[13082:506871] inside -- {number = 1, name = main}
2019-04-08 15:24:15.335725+0800 GCDDemo[13082:506871] inside -- 0
2019-04-08 15:24:15.335796+0800 GCDDemo[13082:506871] inside -- 1
...
2019-04-08 15:24:15.336425+0800 GCDDemo[13082:506871] inside -- 9
2019-04-08 15:24:15.336583+0800 GCDDemo[13082:506871] outside -- 0
2019-04-08 15:24:15.336770+0800 GCDDemo[13082:506871] outside -- 1
...
2019-04-08 15:24:15.343693+0800 GCDDemo[13082:506871] outside -- 9
2019-04-08 15:24:15.343779+0800 GCDDemo[13082:506871] outside end -- {number = 1, name = main}
結論:
， ， 。
3.dispatch_barrier_asyncとdispatch_barrier_sync
barrierの役割は、barrierの前のタスクを実行してからbarrierの後のタスクを実行することです.