The Basics you should know : Processors

This article is for those who wants to know all the basic working, concepts and terms of a processor and on what parameters its performance depends on.

We all have came across the word “Processor” and/or “CPU”. Now, what exactly a processor or a CPU is ? Why it is important ?

Many of you recognize the left image as the CPU. But in professional, it is called as a ‘Cabinet’ or a ‘Computer Chassis’. What actual CPU or the Processor is called can be seen in the right image.

By the definition on Wikipedia -

A central processing unit (CPU), also called a central processor or main processor, is the within a that executes that make up a .

It is a Chip or say a Hardware part present in the Cabinet embedded on the motherboard. CPU stands for ‘Central Processing Unit’. As the name suggests, it is a Processing Unit responsible for all the processes and the operations performed by any computer, laptop or gadget (with embedded CPU), managing and running Operating System and other applications. What processor does is- it takes the input data, processes the data and generates the useful output data. Input data can be anything like a button press from any input device like Keyboard, Mouse or a Controller; a request from any running software to perform a task or operation, etc. Every thing we see on screen or any background process that is running and operating is the result of processed/processing data by the CPU. Even if you move a mouse, the moving cursor that we see in the screen is because of the processor processing all this event/task/operation.

As the processor or CPU is responsible for every task or operation performed by a computer, CPU is called as ‘The Brain of Computer’. Hence, the CPU is one of the most important element in computer which has direct impact on the performance of Computer. Performance of computer not only depends on the CPU or the processor but also the other elements like, , , or , etc. also affects the performance. Intel and AMD are the two most famous and reputed Processor companies where Intel is the most selling Processor brand. For the mobile processors, Brands ruling the market are Apple, Huawei, Qualcomm Snapdragon and Samsung.

Basic understanding of involved Technical Terms and Architecture of a Processor

Now we know why the processors are important and the performance of any computer rely on the Processor. It is the basic logic that the performance of any processor will depend on its design and architecture. Every processor model has different architecture and the set of components like Registers, Arithmetic Logical Unit, Cache Memory, etc, present in it. The important and basic technical terms/components you should know about the processors to judge the quality and capacity of any processor are -

1. Processor Core(s) : The speed at which your processor’s cores and clock speed work together is considered as its processing speed. Processor Core is nothing but the individual processing unit or say processor within the CPU. One core handles only one process or task unless it supports Hyper-Threading(Intel) or Simultaneous Multithreading(SMT)(AMD) which will be explained in the next point. Processors with two or more core are known as Multi core processors. Current processors comes with 2 cores (Dual Core), 4 cores (Quad Core) or 8 cores (Octa Core). Most of the computers has at least dual core processors which enables computers to do multitasking. Today the reason why we are able to run multiple applications at the same time (parallel processing) is because of the multi core processors where each core handles different task/application in parallel or simultaneously. For example, we can do our work on computer along with listening to music, some data being downloaded in browser, etc all these multiple tasks are handled by separate cores.
2. Threads/Threading/Multi-Threading : Thread is the virtual core or code created in a processor core which is used by a application for multitasking. This helps in execution of multiple task of same process at the same time. So, Multi-Threading is a technique in which multiple threads are created (as per the requirement within operating system) for enabling the multitasking is called as Multi-Threading. There are many processors which supports this technique of multithreading. As mentioned in previous of topic of Processor Core- In Intel Processors, this technique is referred as Hyper-Threading and in AMD Processors, this technique is referred as Simultaneous Multithreading(SMT). Each core has one primary thread can have at most 2 threads because of which for example, if you have dual core processor then you can have atmost 4 threads. Request for a thread, creation of threads, allocation of task to a thread all this task are handled by the user Program code and Operating System. For example take the scenario when you are using multiple tabs, on one tab — video is streaming and on the other tab you are monitoring download status. These two task by same application can be handled by same core but two different threads.
3. Clock Speed : Clock Speed is the frequency of a processor or say it is the rate at which processor can complete a processing cycle(The sequence of the events in processing information : Input → Processing → Storage → Output). Clock speed determines how quickly CPU can execute the task. Better clock speed enables the computer to perform more number of tasks by performing the tasks faster which reflects the performance of processor or how fast it is. As the Clock speed is a frequency, it is measured in Megahertz(MHz) which is equal to one Million cycles per second or Gigahertz(GHz) which is equal to one Billion cycles per second. Higher the frequency, better is the performance. For heavy usage in computers, Clock speeds 3.5 GHz–4.0 GHz are considered. For home usage or mid-level usage Clock speeds of 2.4 GHz-3.0 GHz are considered. Speed and performance not only depends on the clock speed, things can get confusing as it also depends on the architecture of the CPU and its other hardware configuration. Processor with 3.5 GHz and better adjustments with high quality hardware specs can out perform processor supports clock speed of 4.0 GHz. Multiple cores, cache memory, word length, address bus width, and data bus width all affect the performance and speed of your CPU. This proves that the processor with higher clock speed can outperform processor with lower clock speed only if the other factors are equal. Side Fact — Record for the highest clock speed is : 8.723 GHz by AMD Piledriver-based FX-8370 chip
4. Processor Cache Memory : Cache Memory is extremely fast and smaller memory used by CPU. Cache memory is used by CPU to reduce the time required to fetch the required data from the main memory. This required data is the data of the application that is running in main memory and required by the CPU to perform and execute specific task requested by the application or assigned by system(OS). Cache memory keeps the copy of most frequently used data and its address in the Cache Memory from the main memory for faster access to that data as cache is closer to CPU and can provide faster access to data. If the data that CPU is looking for is found in cache then it is called as Cache Hit (Good thing as access to data is quick which gives better speed and performance to run/execute application/task and saves extra time required to fetch data from main memory which is a longer route). If the data is not found in Cache, then this is called as Cache Miss (Bad thing as now CPU will have to search for the required data in main memory and then copy it in Cache Memory). There are three(stable) different levels(Types) of Cache Memory — L1 (Level 1), L2(Level 2) and L3(Level 3). L1 — L1 is the primary cache embedded on processor chip which is fastest but smaller in size. When the data or information is required then the processor first looks in the L1 cache. L2 — L2 is secondary cache which is slower than L1 but has more size. L2 is either embedded on Processor chip or often on a separate chip between CPU and RAM with a high speed bus that connects it with CPU. If the instructions or data not found in L1 then CPU searches for it in L2. L3 — L3 cache is slower than L2 cache but has double speed than the DRAM. Each core can have separate L1 and L2 cache, but all cores of CPU share common L3 cache.

Conclusion : The performance of Processor depends on- how quickly it gets the data required for execution of assigned task (Cache hit/Miss, speed of RAM/Main Memory, speed of Bus, etc), at what Clock Speed the processor is running, how quickly it manages to write back in respective memory location and provide appropriate acknowledgement or output to user or system. Hence, not only good equipped processor but other hardware components like , , or , etc also plays an important role in providing greater performance. Next time whenever you will be buying a computer or mobile make sure that the processor has good balance between the number of cores and clock speed if you are expecting negligible slowdowns and quicker responses.

“Zero lag or slowdown is just a myth”

I hope you have enjoyed this article. If you have any suggestion or point do comment and share it with me and other readers. Thank You.

|Gmail- [email protected] ||Instagram username- |