Superscalar architecture is a type of microprocessor design and construction that makes it possible for a processor to work on multiple sets of instructions at the same time – by sending them through separate execution units. Each unit can still only handle one set of instructions in order at a time, however it is possible to have multiple units run concurrently.
Superscalar architecture requires the use of a built-in scheduler that looks through the instruction queue and identifies groups and sets of instructions that don’t conflict with one another.
Technipages Explains Superscalar Architecture
In other words, ones that do not require use of the same resources at the same time. These sets of instructions can run parallel since they don’t have to ‘fight’ for resources, such as it were. However many groups and sets can be grouped together are then passed along for execution.
The only limitation is the number of pipelines available. The Intel Pentium chip features two – this means that the processor is able to execute two sets of instructions per singular clock cycle. These clock cycles are measured in hertz – a 2Ghz processor, which is at the lower end of current capabilities, can process two billion instructions per second. Although that may sound like a lot, it’s not uncommon for a processor to have to execute tens or even hundreds of thousands of instructions for a high-intensity program.
Superscalar architecture in processors enables them to perform the necessary computations more effectively, by assigning spare resources to other tasks in the second (or any further) pipelines. In contrast, a scalar processor would simply not use resources that aren’t needed for a process, even if hey could be useful for another set of processes.
Common Uses of Superscalar Architecture
- Superscalar architecture represents a more efficient type of processor structure.
- Though not always, superscalar architecture is usually pipelined as well.
- In a superscalar CPU the dispatcher reads instructions from memory and decides which ones can be run in parallel by allocating the right resources.
Common Misuses of Superscalar Architecture
- Superscalar architecture is an improved type of processor design that replaced scalar ones in Intel processors.