多周期数据路径和流水线数据路径之间的差异

1. 多周期数据通路：
多周期数据路径将指令分解为单独的步骤。每一步都需要一个时钟周期 每个功能单元在一条指令中可以多次使用，只要在不同的时钟周期中使用即可。它减少了所需的硬件数量。它减少了平均指令时间。

2. 管道数据路径：
流水线的目标是允许同时执行多条指令。我们可能需要在一个循环中执行多个操作。递增PC并同时添加寄存器。获取一条指令，而另一条指令读取或写入数据。

与单周期数据路径一样，流水线处理器需要复制同一时钟周期所需的硬件元素。

多周期数据路径和流水线数据路径之间的差异：

S.No.	Multiple Cycle Datapath	Pipeline Datapath
1	Instructions are divided into artitoray number of steps.	Instructions are divided into one per stage.
2	Clock cycles are short but long enough for the lowest instruction.	Clock cycles are short but long enough for the lowest instruction.
3	There are only 1 instruction that can be executed at the same time.	There are as many instructions as pipeline stages.
4	There is a variable number of clock cycles per instructions.	There is a fixed number of clock cycles per instruction, one for each pipeline stage, i.e., CPI = k.
5	Control unit generates signals for the instruction’s current step and keeps track of the current step.	Control unit generates signals for the entire instruction; these signals are propagated from one pipeline stage to another via the pipeline registers.
6	There is no duplicate hardware, because the instructions generally are broken into single FU steps.	There is duplicate hardware, so that there are no restrictions on which instructions can be in the pipeline simultaneously.
7	Extra registers are required to hold the result of one step for use in the next step.	Extra registers are required to provide the results of one pipeline stage to the next pipeline stage.
8	Performance is slightly slower to mederaletly faster than single cycle, latter when the instructions steps are well balanced and a significantly fractions of the instructions take less than the maximum number of cycles.	Performance is moderately faster to significantly faster than a single cycle.