Activity is a unit of instruction execution, and is the building block of a process.
活动(activity)是指令执行的一个单元，它是一个流程的基本组成部分。
2
An executable unit begins at the start of every basic block and at any instruction that corresponds to a line of source code that is different than the previous instruction.
一个可执行的单元由每一个基本快开始，而与每行源代码相对应的指南与前面版本中的指南有所不同。
3
Neither a memory management unit nor an instruction or data cache are used.