小编Chr*_*ler的帖子

我试图NSURLConnection通过iPhone 了解3G网络的性能.我有以下测试代码

-(void)doTest2 {
     max = 5;
     NSURL *url = [NSURL URLWithString:@"http://www.google.com"];
     NSURLRequest *request2 = [[[NSURLRequest alloc] initWithURL:url] autorelease];  
     NSURLConnection *conn=[[NSURLConnection alloc] initWithRequest:request2 delegate:self];  
     self.startDate = [NSDate date];
     if (conn)   
     {  
        receivedData = [[NSMutableData data] retain];  
     }  }   

- (void)connectionDidFinishLoading:(NSURLConnection *)connection {  
       self.endDate = [NSDate date];
       NSTimeInterval interval = [self.endDate      timeIntervalSinceDate:self.startDate];
       NSLog(@"Time:%f Size:%u", interval, [receivedData length]);
      [receivedData release];  

       count = count + 1;
       if (count == max) { 
          count = 0;
          sleep(3);
       }
       self.doTest2;}

第一个请求很慢(超过1秒).请求2-5很快(低于0.25秒).如果我睡了3秒或更长时间,睡眠后的第一个请求很慢.但如果我睡了不到3秒钟,那就快了.有什么想法吗？