A scenario is a "thread" through the use case -- i.e. the basic flow plus zero or more alternate flows.

1一个场景就是一个“思路”的观念贯穿了这个用例的全过程——即一个基本的信息流加上零或者更多备选的信息流。

youdao

This requires minimal resources while the process waits, in particular, Play is capable of working of a mini-thread pool (typically the number of processors on your machine plus one).

这样在处理等待时就可以将所需的资源降到最低限度，特别地，Play使用了一个微型的线程池（通常数量为机器上的处理器个数加上1）。

youdao

Plus the cost of creating a new thread is relatively large, so resulting in low efficiency.

再加上创建新线程的开销比较大，所以造成了效率的低下。

youdao

When I think about the history of the US, and what has carried us through past two hundred plus years as a nation, I see again and again this thread of youthful, optimistic, we-can-do-something energy.

FORBES: The Thing That Made America Great - Do We Still Have It?