Multi-core processor

A multi-core processor is a special kind of chip that has two or more parts called cores. Each core can do tasks, like adding numbers, all at the same time. This helps computers work faster, especially for tasks that can be split up.

These processors can have different setups. Some cores share things like memory space, while others talk to each other in different ways. There are also chips where the cores are not all the same.

In everyday computers, dual-core processors became common in the late 2000s. By the early 2010s, computers with four cores, called quad-core, started showing up more often. Now, many computers have even more cores, helping them handle lots of work at once.

Terminology

The words multi-core and dual-core usually talk about central processing units, or CPUs. But they can also be used for digital signal processors and systems on chip. These words are mostly used for CPUs made on the same tiny piece of material, called an integrated circuit.

When CPUs are in the same package but made separately, they are called something else, like a multi-chip module.

The word multi-CPU means several separate processing units that are not on the same piece of material. Words like many-core and massively multi-core are used when there are lots and lots of cores — maybe tens or even thousands! Some systems have many soft microprocessor cores on a single FPGA. Each of these “cores” can act like a small CPU core and a special piece of design called a "semiconductor intellectual property core".

Development

As technology got better, the tiny parts of computer chips got smaller. Designers had to solve problems like managing heat and coordinating data. To make computers faster, designers let different parts work on tasks at the same time. One way to do this was to use several small processors, called cores, on a single chip. This created multi-core processors.

Apple once planned to make a special chip with four cores, but the technology wasn’t ready yet. Later, researchers at Stanford University showed that putting many processors on one chip was possible. This helped shape today’s multi-core processors. Companies like Intel saw benefits in making chips with multiple cores. This let them improve performance while managing heat and power use. Multi-core designs also helped overcome limits in making processors faster by letting different cores work together.

Hardware

Computers now have chips with many small parts, called cores, all working together. Some chips can have hundreds or thousands of these cores. This helps them work faster, especially for things like watching videos or going online.

There are different ways to make these chips. Some chips use the same kind of core many times. Others use different kinds of cores for special jobs. This choice is important for people who make software and for people who use the devices. For example, a device called "True Octa-core" has eight separate cores working together.

Software effects

When software runs on a computer with more than one core, it sometimes has trouble using all the cores well. This is because some tasks, like parts of watching videos, can only be done by one part of the computer at a time.

Many jobs, such as sending information over the internet, work better with several cores. Special ways to write software for many cores exist, and companies like Intel have made tools to help with this. Sharing work across many cores can be hard, especially when the cores are different.

On servers, which are computers many people use together, several cores help a lot. They let many tasks happen at once, making websites and online services faster and better for everyone.

Embedded applications

Embedded computing uses processors that are not the same as those in regular computers. These processors can have more than one core, which helps them complete tasks more quickly if the work can be divided between the cores.

Because embedded software is created for particular hardware, it is simpler for developers to use new technologies. This leads to many different kinds of multi-core processors being available.

Network processors

Since 2010, many companies have made special processors for networks with multiple cores. Companies like Freescale Semiconductor, Cavium Networks, Wintegra and Broadcom are examples. These processors can do eight tasks at once. But using all these cores well can be hard because of limits in how the system works. Some companies, like 6WIND, help by making software that works faster.

Digital signal processing

In digital signal processing, the same idea is used. Companies like Texas Instruments make chips with three and four cores. Freescale makes chips with four and six cores, and they are working on chips with eight cores. New companies include the Storm-1 family from [Stream Processors, Inc] and Picochip with many processors for communication tasks.

Heterogeneous systems

In heterogeneous computing, a system can use more than one kind of processor. Multi-core setups are now more common. For example, the Xilinx Zynq UltraScale+ MPSoC has a quad-core ARM Cortex-A53 and a dual-core ARM Cortex-R5. Special software like OpenAMP helps these processors work together.

Mobile devices often use the ARM big.LITTLE architecture to manage their processors better.

Hardware examples

Many modern computers use multi-core processors. These chips have several "cores," or small brains, that work together to make the computer faster. Some famous examples include:

• AMD: Makes many processors with different numbers of cores, like the Ryzen and Epyc series.
• Intel: Offers processors like Core i3, Core i5, and Core i7, which have anywhere from two to eighteen cores.
• IBM: Creates powerful servers with processors like Power9 and Power10, which can have up to 30 cores.
• ARM: Provides designs used in many phones and tablets, often with multiple cores for better performance.

These processors help computers run many tasks at once, making them faster and more efficient.

Benchmarks

When scientists create multi-core processors, they need ways to test and compare them. They use special tests called benchmarks for this. Some well-known benchmarks are SPLASH-2, PARSEC, and COSMIC. These help test different kinds of systems.