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Can some explain to me how the number of cores affects the performance of the CPU?

Please don't tell me to research it because I already have and I need someone to explain it to me
You only need to think about it. What does a processor do? What job does it serve? If you have more cores (processors), what impact do you think that will have on the work needing to be done? Is one person filling jam jars with jam better or worse than 4 people filling jam jars? It isn't rocket science.

Good luck!
Reply 2
The runway = A core

You have a runway and you want planes to land. They keep landing one after the other. But let's say you want one to take off, the one's that have to land have to stop for a second so some can take off.

Let's say you have 2 cores now.

One for landing one for taking off. You can now land and make planes take off, let's say you want to taxi some planes and there is no room, you have to stop either the landing / taking off the planes in order to do that.

Let's say you have 3 cores now.

One for landing/taking off, and the last one for anything you want e.g taxiing.

What cores do, it allows you to do things during the same time and prevents large queues from happening on one core. Hence why some games cant run on single core because there are loads of variables you want to load at the same time and not having them queueing causing FPS drop, etc.
Reply 3
Original post by ByEeek
You only need to think about it. What does a processor do? What job does it serve? If you have more cores (processors), what impact do you think that will have on the work needing to be done? Is one person filling jam jars with jam better or worse than 4 people filling jam jars? It isn't rocket science.

Good luck!


The more cores that you have = the faster instructions can be fetched and executed ?
Original post by JackT2000
The more cores that you have = the faster instructions can be fetched and executed ?


Not quite. If you have one man filling jam jars and you add another three men, the first man doesn't start filling jam jars quicker does he? But what happens to the rate of jam jars being filled as a whole now four men are working on it?
Reply 5
Original post by ByEeek
Not quite. If you have one man filling jam jars and you add another three men, the first man doesn't start filling jam jars quicker does he? But what happens to the rate of jam jars being filled as a whole now four men are working on it?


If you add more cores to a computer more instructions can be executed per second. ??

If not could you just spill the beans as I need this for my revision notes and I'm getting stressed because I don't know
(edited 7 years ago)
Original post by JackT2000
If you add more cores to a computer more instructions can be executed per second. ??

If not could you just spill the beans as I need this for my revision notes and I'm getting stressed because I don't know


That's pretty much it. Yes. More cores = more instructions per second. In Windows world, you can allocate threads and processes to cores to give truly multi-processor functionality as opposed to the virtual multi-processor capability single core systems utilise by time slicing and other strategies.

I am not being difficult on purpose. You genuinely need to understand this stuff. Copying it off the internet into your book won't help anyone. So when a multi-core question comes up in your exam, just think about men filling up jam jars! :smile:

Good luck!
Original post by ByEeek
That's pretty much it. Yes. More cores = more instructions per second. In Windows world, you can allocate threads and processes to cores to give truly multi-processor functionality as opposed to the virtual multi-processor capability single core systems utilise by time slicing and other strategies.

I am not being difficult on purpose. You genuinely need to understand this stuff. Copying it off the internet into your book won't help anyone. So when a multi-core question comes up in your exam, just think about men filling up jam jars! :smile:

Good luck!


But do remember that you can get better CPU cores so it may not always be more cores=more instructions per second. but generally it is.
Reply 8
Original post by ByEeek
That's pretty much it. Yes. More cores = more instructions per second. In Windows world, you can allocate threads and processes to cores to give truly multi-processor functionality as opposed to the virtual multi-processor capability single core systems utilise by time slicing and other strategies.

I am not being difficult on purpose. You genuinely need to understand this stuff. Copying it off the internet into your book won't help anyone. So when a multi-core question comes up in your exam, just think about men filling up jam jars! :smile:

Good luck!



Ok this is an exam question that I have found "describe the benefits of a dual core processor over a single core processor"

What would I write for my answer I'm not sure how I would structure it?

Quick question : Is a dual core processor two separate CPUs that are on the motherboard ?
Reply 9
Original post by JackT2000
Please don't tell me to research it because I already have and I need someone to explain it to me


Do some research
Reply 10
Original post by JackT2000
If you add more cores to a computer more instructions can be executed per second. ??

If not could you just spill the beans as I need this for my revision notes and I'm getting stressed because I don't know





If not could you just spill the beans as I need this for my revision notes and I'm getting stressed because I don't know
Some commands need to be done at the same time, and this is what different cores help with. 1 core has a queue of commands whereas if you had 2 cores, you still have the same processing power, but it is split into doing 2 tasks that need to be done at the same time.

You have less instructions executed, but its the way its intended. so more cores only benefits programs that require to split the instructions example is gaming - more cores help.
Original post by JackT2000

Quick question : Is a dual core processor two separate CPUs that are on the motherboard ?


Yes. Effectively two processors inside one piece of silicon mounted on the motherboard.

Just think about it. Imagine you have two programmes running on only one core. Now suddenly you have two programmes running on two cores. What will that look like to the user?

What might some disadvantages of having two cores be? Power? Heat? Efficiency? What if your program is single threaded i.e. can only run on one processor? Is there any advantage to having two cores?

Write something down and then go back and improve it. This is tricky stuff and it is ok to find it hard. You do need to just work it through.
Original post by AperfectBalance
But do remember that you can get better CPU cores so it may not always be more cores=more instructions per second. but generally it is.


I take your point, but this is the wild world of academia where Unicode is 16 bits, gravity is 10m/s^2 and pulleys are frictionless.
Reply 13
Original post by ByEeek
Yes. Effectively two processors inside one piece of silicon mounted on the motherboard.

Just think about it. Imagine you have two programmes running on only one core. Now suddenly you have two programmes running on two cores. What will that look like to the user?

What might some disadvantages of having two cores be? Power? Heat? Efficiency? What if your program is single threaded i.e. can only run on one processor? Is there any advantage to having two cores?

Write something down and then go back and improve it. This is tricky stuff and it is ok to find it hard. You do need to just work it through.


Thanks there is hardly any revision materials for GCSE computing.

Would this be a good answer? :

The benefits of using a dual core processor is that it can execute twice as many instructions per second than a single core processor.
Original post by JackT2000
Thanks there is hardly any revision materials for GCSE computing.

Would this be a good answer? :

The benefits of using a dual core processor is that it can execute twice as many instructions per second than a single core processor.


This would describe a processor with twice higher frequency.

I would rather make such definition:
A processor with two cores allows two tasks to be executed simultaenously in real time.

Somebody else give feedback please, because I'm not a computer scientist.
Original post by JackT2000
Thanks there is hardly any revision materials for GCSE computing.

Would this be a good answer? :

The benefits of using a dual core processor is that it can execute twice as many instructions per second than a single core processor.


If the question is a two pointer, you might get one point for that answer. Have you not found BBC Bitesize yet? Honestly, it is brilliant. For OCR computing, you don't need much depth, there is just a lot of topics.

http://www.bbc.co.uk/education/guides/zmb9mp3/revision/2

You could also try the Cambridge Mooc
http://cambridgegcsecomputing.org/

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