3.1.3 | CPU CACHE AND CLOCK

Topics from the Cambridge IGCSE (9-1) Computer Science 0984 syllabus 2023 - 2025.

3.1.3 Understand what is meant by a core, cache and clock in a CPU and explain how they can affect the performance of a CPU
The number of cores, size of the cache and speed of the clock can affect the performance of a CPU

ALSO IN THIS TOPIC
3.1.1 COMPUTER ARCHITECTURE 
3.1.2 COMPUTER ARCHITECTURE 
YOU ARE HERE | ​3.1.3 COMPUTER ARCHITECTURE 
3.1.4 COMPUTER ARCHITECTURE(CIE) 
3.1.5 COMPUTER ARCHITECTURE 
3.2.1 INPUT AND OUTPUT DEVICES 
3.2.2 INPUT AND OUTPUT DEVICES 
3.2.3 INPUT AND OUTPUT DEVICES
3.3 DATA STORAGE 
3.4 NETWORK HARDWARE 
REVISION CARDS
TOPIC 3 KEY TERMINOLOGY
TOPIC 3 ANSWERS
TOPIC 3 TEACHER RESOURCES
TOPIC 1 TEACHER RESOURCES (CIE)

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THE CORE

​In computing, "the core" generally refers to the central processing unit (CPU) of a computer, which is the primary component responsible for executing instructions and performing calculations. The term "core" specifically refers to an individual processing unit within a CPU.

Modern CPUs often have multiple cores, allowing for parallel processing and improved performance. Each core operates independently, allowing multiple tasks to be processed simultaneously. The number of cores in a CPU can have a significant impact on the overall performance and efficiency of a computer system.

In summary, "the core" refers to the individual processing unit within a CPU that performs the calculations and executes the instructions necessary to run a computer system.

CACHE

​In computing, a cache is a small, high-speed memory that stores frequently used data for quick access. The purpose of a cache is to speed up the processing of data by storing it temporarily so that it can be quickly retrieved and used again, instead of having to be fetched from a slower storage device such as a hard drive or main memory.

There are different types of cache memory, including processor cache, disk cache, and web browser cache. Processor cache, also known as CPU cache, is a small amount of memory built into a processor that stores recently processed data for quick access. Disk cache is used to temporarily store data that has been recently read from a hard drive, while web browser cache stores frequently visited web pages and other resources on a user's local machine, allowing them to be quickly loaded the next time they are needed.

In general, the use of cache memory can significantly improve the performance of a computer system by reducing the amount of time it takes to access and process data.

THE CLOCK

​In computing, the clock refers to a timing circuit that generates regular pulses used to synchronize the operations within a computer. The clock controls the speed at which the CPU operates, and is typically measured in GHz (gigahertz). The higher the clock speed, the more instructions the CPU can execute per second.

The clock sends out pulses at regular intervals, which are used to coordinate the activities of the various components within the computer, such as the memory, I/O devices, and the CPU itself. The clock speed is a crucial factor in determining the overall performance of a computer, as a faster clock speed can lead to improved processing speed and increased responsiveness.

In summary, the clock in a computer is a timing circuit that generates regular pulses used to coordinate the operations within the system and control the speed of the CPU.

OVERALL PERFORMANCE OF THE CPU

To summarise, ​the number of cores, size of the cache, and speed of the clock are three key factors that can affect the performance of a CPU.

The number of cores refers to the number of independent processing units within a CPU, and a higher number of cores allows for parallel processing and improved performance.

The size of the cache refers to the amount of high-speed memory built into the CPU, and a larger cache size can store more frequently used data for quick access, improving the processing speed.

The speed of the clock, measured in GHz (gigahertz), refers to the frequency at which the timing circuit generates regular pulses, and a higher clock speed allows the CPU to execute more instructions per second, leading to improved processing speed and increased responsiveness.

Overall, a CPU with a high number of cores, a large cache size, and a fast clock speed will typically perform better and provide a more efficient computing experience.

1. What is the role of the Central Processing Unit (CPU) in a computer system?
2. What is a microprocessor and give an example of its use?
3. What is meant by "the core" in computing terms?
4. What is a cache in computing and why is it used?
5. What is the purpose of the clock in a computer system?
6. How does the number of cores in a CPU affect its performance?
7. What is the relationship between the size of the cache and the processing speed of a CPU?
8. How does the clock speed of a CPU impact its performance?
9. Can you explain the difference between processor cache, disk cache, and web browser cache?
10. How does the combination of number of cores, size of cache, and speed of the clock impact the overall performance of a CPU?

ALSO IN THIS TOPIC

3.1.1 COMPUTER ARCHITECTURE | The role of the CPU
3.1.2 COMPUTER ARCHITECTURE | Components of the CPU
3.1.3 COMPUTER ARCHITECTURE | Core's, Cache and Clock speed
3.1.4 COMPUTER ARCHITECTURE(CIE) | The Instruction Set
3.1.5 COMPUTER ARCHITECTURE | Embedded Systems
3.2.1 INPUT AND OUTPUT DEVICES | Input Devices
3.2.2 INPUT AND OUTPUT DEVICES | Output Devices
3.2.3 INPUT AND OUTPUT DEVICES | Sensors
3.3 DATA STORAGE | Primary, Secondary, Virtual and Cloud storage
3.4 NETWORK HARDWARE | Networks, Components and Protocols
REVISION CARDS | Flip cards to help test yourself
TOPIC 3 KEY TERMINOLOGY
TOPIC 3 ANSWERS
TOPIC 3 TEACHER RESOURCES