如果我们只是靠随便网络上查找一个Speculative这个词的含义，是很难去理解的。
但是我们通过查看英文原文去理解，可能就比较清楚地理解了：

speculative
(adjective)

1. based on guessing or on opinions that have been formed without knowing all the facts
The report is highly speculative and should be ignored.

2. showing that you are trying to guess something
She cast a speculative look at Kate.

3. (of business activity) done in the hope of making a profit but involving the risk of losing money
speculative investment

可见这种一种投机性（有对赌性质）的执行策略。也就是反正闲着也是闲着，CPU一直要不闲下来。

参考资料：

https://zh.wikipedia.org/wiki/%E6%8E%A8%E6%B5%8B%E6%89%A7%E8%A1%8C

https://zhuanlan.zhihu.com/p/33145828

https://zhuanlan.zhihu.com/p/32784852