One problem is that when many threads are launched at once some of them, in practice, will fail to obtain a connection, even if the database limit is not reached.

一个问题就是当很多线程被同时启用时，即使还没有达到该数据库的限值，其中的一些线程实际上也不能获得连接。

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The lightning branches out in many different directions, causing one leader to make a connection with the ground, creating a bright return stroke.

闪电在许多不同的方向长出分叉，激发了一个先导与地面连接，制造了一次闪亮的回击。

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