[SHENGTON]

Hello, good afternoon.

Can someone explain to me about the "core" and "thread" in the processor.

Questions:
1. What is core?
2. What is thread?
3. What's the difference between core and thread?

Thanks and God bless.

Edited by SHENGTON, 01 June 2011 - 01:56 AM.

[Advertisements]

A core is the physical CPU. Threads are connections to that core. If you have a quad core CPU it has 4 physical, independent processors inside. A hyperthreaded CPU has two connections to each core.

Think of data as people, CPUs as buildings, threads as doors. Now picture people standing outside, waiting to get in. A single building with a single door is a single core, single threaded CPU. 1 building with 2 doors, it's a single core, hyperthreaded (2 thread) CPU. 4 buildings with 2 doors each would be a quad-core, hyperthreaded CPU.

It would seem the the 4 buildings and 8 doors would get people inside very fast. However, imagine someone has to open the door for every person, and it's your job to tell them when to open it. With one building and one door that's a pretty efficient process. With 4 buildings and 8 doors there are going to be door openers idly waiting for your approval.

This management of data is why cores don't scale linearly, like clock speed. For example, everything else being equal, a 4 GHz CPU is 400% faster than a 1 Ghz CPU. While for most tasks a dual-core CPU will be 150% faster than a single core. A quad core about 175% faster (not 400%).

[admin]

A core is the physical CPU. Threads are connections to that core. If you have a quad core CPU it has 4 physical, independent processors inside. A hyperthreaded CPU has two connections to each core.

Think of data as people, CPUs as buildings, threads as doors. Now picture people standing outside, waiting to get in. A single building with a single door is a single core, single threaded CPU. 1 building with 2 doors, it's a single core, hyperthreaded (2 thread) CPU. 4 buildings with 2 doors each would be a quad-core, hyperthreaded CPU.

It would seem the the 4 buildings and 8 doors would get people inside very fast. However, imagine someone has to open the door for every person, and it's your job to tell them when to open it. With one building and one door that's a pretty efficient process. With 4 buildings and 8 doors there are going to be door openers idly waiting for your approval.

This management of data is why cores don't scale linearly, like clock speed. For example, everything else being equal, a 4 GHz CPU is 400% faster than a 1 Ghz CPU. While for most tasks a dual-core CPU will be 150% faster than a single core. A quad core about 175% faster (not 400%).

[SHENGTON]

Hello admin, good evening.

Thanks for replying my queries Sir. Did you mean "threads" are just passageway?

Take care and God bless.

[admin]

Did you mean "threads" are just passageway?

I think it's a language issue... sure.