cpu execution time

基本解释

The task accounts for its time with the CPU by adding its execution time to the virtual runtime and is then inserted back into the tree if runnable.
任务通过将其运行时间添加到虚拟运行时，说明其占用 CPU 的时间，然后如果可运行，再插回到树中。
The cost can be one of the following metrics: execution time per query execution, user CPU time per query execution, and system CPU time per query execution.
这里所说的成本可能是下面的度量之一：每次查询执行的执行时间、每次查询执行的用户 CPU 时间、以及每次查询执行的系统 CPU 时间。
Experimental comparison with the previous work indicates that it accelerates the sampling speed in the large transaction databases which reduces CPU execution time, and possesses a good scalability.
通过实验分析表明，该算法明显地加快了大事务数据库中采样的速度，从而降低了CPU时间，而且具有很好的可扩展性。