Because you're sharing the same mutex for push and pop operations, the data-read speed is somewhat compromised as writer threads access the lock.

因为添加和取出数据操作使用相同的互斥锁，所以读取数据的速度会影响写数据的线程访问锁。

youdao

The lock will pop open.

锁就会打开了。

youdao

Sliding in the cell locks it in place, where a swipe of the lock lets it pop out so that you can grasp it with your fingers -- it's usually an easy task, but sometimes the battery doesn't pop out enough to get a grip on it.

ENGADGET: Tritton Warhead 7.1 Wireless Surround Sound Headset for Xbox 360 review