Multi core phone CPUs

PencilBreath · 16-01-2013, 13:33

I was reading various articles/comments about the S3 in particular & they were saying that really quad core CPUs in phones are pretty pointless just now as no apps would be optimized to use them & the O/S itself doesn't even use them.

Are they just "future proofing" features then?

BrightSparks · 16-01-2013, 13:55

The theory of multicore processors is this: if you can divvy up a task among more than one processor, you can finish up faster....

TheBigM · 16-01-2013, 14:07

Quote:

Originally Posted by BrightSparks

The theory of multicore processors is this: if you can divvy up a task among more than one processor, you can finish up faster....

And the point of PencilBreath's post was that this "divvying up" is not taking place, in a significantly beneficial manner anyway.

flagpole · 16-01-2013, 14:09

Quote:

Originally Posted by PencilBreath

I was reading various articles/comments about the S3 in particular & they were saying that really quad core CPUs in phones are pretty pointless just now as no apps would be optimized to use them & the O/S itself doesn't even use them.

Are they just "future proofing" features then?

there is truth in that. a bit.

in theory a single process can run over more than one core but it needs to be specifically written to do that. and multithreading apps is hard, not a lot of app designers will do that. but some will, the advanced games and things all do.

even if the app you are running is not multithreaded itself it can max out one core and leave the other cores available for the other things going on. the system functions and all those other apps running in the background. and the app itself will be calling system functions.

multicore is a fudge. we have multicore processors because we can't build single core cpus fast enough.

but it's the only thing we have.

The Sack · 16-01-2013, 15:31

Quote:

Originally Posted by PencilBreath

I was reading various articles/comments about the S3 in particular & they were saying that really quad core CPUs in phones are pretty pointless just now as no apps would be optimized to use them & the O/S itself doesn't even use them.

Are they just "future proofing" features then?

Bragging rights i guess.

when i moved from a single core PC to a dual core one i noticed a massive difference, when i moved from a dual core PC to a quad core PC i noticed no difference.

When i moved from a single core android phone to a dual core one i noticed no difference so i cant see a quad core one suddenly being amazing based just on the fact it is quad core.

red_g00ner · 16-01-2013, 16:14

The next gen multi-cores should have better battery life from what l read a while back.

Essentially you will have the normal quad cores and then a fifth slower core, so that when your not using the phone, i.e. in standby, everything switches to the 5 low power/slower one

Gormond · 16-01-2013, 16:44

Quote:

Originally Posted by red_g00ner

The next gen multi-cores should have better battery life from what l read a while back.

Essentially you will have the normal quad cores and then a fifth slower core, so that when your not using the phone, i.e. in standby, everything switches to the 5 low power/slower one

This is not new, the Tegra 3 SoC can do this, as does the new Tegra 4 SoC.

IvanIV · 16-01-2013, 17:01

Games (or anything that renders a scene) and GPUs can benefit greatly from multiple cores. It is possible to divide a scene/screen into independent regions and calculate their rendering fully in parallel. I do not know if any game framework already support this. But once you reach a necessary complexity and a framerate it does not make sense to have more power. And in general there's not a lot of tasks that need more cores. To get a responsive system 2 cores are usually enough.

At the moment a number of cores is just a gimmick, a pissing contest, IMO.

paulbrock · 16-01-2013, 17:15

and presumably when you have several apps/processes running, it can keep the background tasks going without affecting the speed of the foreground task. So your live wallpaper,widgets and other apps won't cause a slowdown.

flagpole · 16-01-2013, 17:19

Exactly

Mark in Essex · 16-01-2013, 17:33

Like others have said its mainly for the better battery life as a 1 core on a 4 core processor will use less than 1 core on a 2 core processor.

That's one of the reasons servers nowadays do that for when they are not in use.

Gormond · 16-01-2013, 17:59

Quote:

Originally Posted by Mark in Essex

Like others have said its mainly for the better battery life as a 1 core on a 4 core processor will use less than 1 core on a 2 core processor.

That's one of the reasons servers nowadays do that for when they are not in use.

That's only true if the architecture of the quad core chip is newer than that of the single core.

For example one core of a dual core A15 uses less power than one core of a quad core A9.

flagpole · 16-01-2013, 18:01

Quote:

Originally Posted by Mark in Essex

Like others have said its mainly for the better battery life as a 1 core on a 4 core processor will use less than 1 core on a 2 core processor.

That's one of the reasons servers nowadays do that for when they are not in use.

There's nothing fundamental about why one core on a quad would use less power than one on a dual. Besides you have four of them.

IvanIV · 16-01-2013, 19:02

Quote:

Originally Posted by flagpole

There's nothing fundamental about why one core on a quad would use less power than one on a dual. Besides you have four of them.

Apparently one or more cores should be low power consumption low performance, which is enough for background processing when phone is in standby. When more intensive tasks are running the other cores are used instead.

flagpole · 16-01-2013, 19:28

Quote:

Originally Posted by IvanIV

Apparently one or more cores should be low power consumption low performance, which is enough for background processing when phone is in standby. When more intensive tasks are running the other cores are used instead.

Fo shizzle.

If they are designed that way. In general though....

PencilBreath · 16-01-2013, 19:35

Quote:

Originally Posted by red_g00ner

The next gen multi-cores should have better battery life from what l read a while back.

Essentially you will have the normal quad cores and then a fifth slower core, so that when your not using the phone, i.e. in standby, everything switches to the 5 low power/slower one

I thought modern cores park when not in use so is that not the same?

whoever,hey · 16-01-2013, 19:44

Quote:

Originally Posted by PencilBreath

I thought modern cores park when not in use so is that not the same?

The last time i heard the term 'park' was in parking the head of a HDD

.

PencilBreath · 16-01-2013, 20:05

http://i53.photobucket.com/albums/g6...ps3779be62.png

https://www.google.co.uk/search?q=Co...ient=firefox-a

Perhaps it's just a windows feature.

flagpole · 16-01-2013, 20:18

I've never heard of it either. In that picture it looks to be the virtual/hyperthreaded cores that are parked.

Gormond · 16-01-2013, 20:25

Quote:

Originally Posted by PencilBreath

http://i53.photobucket.com/albums/g6...ps3779be62.png

https://www.google.co.uk/search?q=Co...ient=firefox-a

Perhaps it's just a windows feature.

I think you are getting confused, only threads can be parked not cores.

Although when idle CPUs don't consume much power any way.

16-01-2013, 13:33	#1
PencilBreath Forum Member Join Date: Dec 2010 Location: Here. Posts: 3,345	Multi core phone CPUs I was reading various articles/comments about the S3 in particular & they were saying that really quad core CPUs in phones are pretty pointless just now as no apps would be optimized to use them & the O/S itself doesn't even use them. Are they just "future proofing" features then?

16-01-2013, 13:55	#2
BrightSparks Forum Member Join Date: Nov 2005 Location: uk Posts: 1,029	The theory of multicore processors is this: if you can divvy up a task among more than one processor, you can finish up faster....

16-01-2013, 14:07	#3
TheBigM Forum Member Join Date: Aug 2004 Location: moon Posts: 12,983	Quote: Originally Posted by BrightSparks The theory of multicore processors is this: if you can divvy up a task among more than one processor, you can finish up faster.... And the point of PencilBreath's post was that this "divvying up" is not taking place, in a significantly beneficial manner anyway.

16-01-2013, 14:09	#4
flagpole Inactive Member Join Date: Jan 2003 Posts: 43,524	Quote: Originally Posted by PencilBreath I was reading various articles/comments about the S3 in particular & they were saying that really quad core CPUs in phones are pretty pointless just now as no apps would be optimized to use them & the O/S itself doesn't even use them. Are they just "future proofing" features then? there is truth in that. a bit. in theory a single process can run over more than one core but it needs to be specifically written to do that. and multithreading apps is hard, not a lot of app designers will do that. but some will, the advanced games and things all do. even if the app you are running is not multithreaded itself it can max out one core and leave the other cores available for the other things going on. the system functions and all those other apps running in the background. and the app itself will be calling system functions. multicore is a fudge. we have multicore processors because we can't build single core cpus fast enough. but it's the only thing we have.

16-01-2013, 15:31	#5
The Sack Forum Member Join Date: Jan 2003 Location: S6 1SW WTID UTO FTB Posts: 6,327	Quote: Originally Posted by PencilBreath I was reading various articles/comments about the S3 in particular & they were saying that really quad core CPUs in phones are pretty pointless just now as no apps would be optimized to use them & the O/S itself doesn't even use them. Are they just "future proofing" features then? Bragging rights i guess. when i moved from a single core PC to a dual core one i noticed a massive difference, when i moved from a dual core PC to a quad core PC i noticed no difference. When i moved from a single core android phone to a dual core one i noticed no difference so i cant see a quad core one suddenly being amazing based just on the fact it is quad core.

16-01-2013, 16:14	#6
red_g00ner Forum Member Join Date: Apr 2003 Location: UK Posts: 790	The next gen multi-cores should have better battery life from what l read a while back. Essentially you will have the normal quad cores and then a fifth slower core, so that when your not using the phone, i.e. in standby, everything switches to the 5 low power/slower one

16-01-2013, 16:44	#7
Gormond Forum Member Join Date: Jul 2006 Location: Scotland Posts: 15,714	Quote: Originally Posted by red_g00ner The next gen multi-cores should have better battery life from what l read a while back. Essentially you will have the normal quad cores and then a fifth slower core, so that when your not using the phone, i.e. in standby, everything switches to the 5 low power/slower one This is not new, the Tegra 3 SoC can do this, as does the new Tegra 4 SoC.

16-01-2013, 17:01	#8
IvanIV Forum Member Join Date: May 2006 Posts: 25,199	Games (or anything that renders a scene) and GPUs can benefit greatly from multiple cores. It is possible to divide a scene/screen into independent regions and calculate their rendering fully in parallel. I do not know if any game framework already support this. But once you reach a necessary complexity and a framerate it does not make sense to have more power. And in general there's not a lot of tasks that need more cores. To get a responsive system 2 cores are usually enough. At the moment a number of cores is just a gimmick, a pissing contest, IMO.

16-01-2013, 17:15	#9
paulbrock Forum Member Join Date: Apr 2002 Location: Wapping, London Posts: 16,222	and presumably when you have several apps/processes running, it can keep the background tasks going without affecting the speed of the foreground task. So your live wallpaper,widgets and other apps won't cause a slowdown.

16-01-2013, 17:19	#10
flagpole Inactive Member Join Date: Jan 2003 Posts: 43,524	Exactly

16-01-2013, 17:33	#11
Mark in Essex Forum Member Join Date: Mar 2005 Posts: 3,644	Like others have said its mainly for the better battery life as a 1 core on a 4 core processor will use less than 1 core on a 2 core processor. That's one of the reasons servers nowadays do that for when they are not in use.

16-01-2013, 17:59	#12
Gormond Forum Member Join Date: Jul 2006 Location: Scotland Posts: 15,714	Quote: Originally Posted by Mark in Essex Like others have said its mainly for the better battery life as a 1 core on a 4 core processor will use less than 1 core on a 2 core processor. That's one of the reasons servers nowadays do that for when they are not in use. That's only true if the architecture of the quad core chip is newer than that of the single core. For example one core of a dual core A15 uses less power than one core of a quad core A9.

16-01-2013, 18:01	#13
flagpole Inactive Member Join Date: Jan 2003 Posts: 43,524	Quote: Originally Posted by Mark in Essex Like others have said its mainly for the better battery life as a 1 core on a 4 core processor will use less than 1 core on a 2 core processor. That's one of the reasons servers nowadays do that for when they are not in use. There's nothing fundamental about why one core on a quad would use less power than one on a dual. Besides you have four of them.

16-01-2013, 19:02	#14
IvanIV Forum Member Join Date: May 2006 Posts: 25,199	Quote: Originally Posted by flagpole There's nothing fundamental about why one core on a quad would use less power than one on a dual. Besides you have four of them. Apparently one or more cores should be low power consumption low performance, which is enough for background processing when phone is in standby. When more intensive tasks are running the other cores are used instead.

16-01-2013, 19:28	#15
flagpole Inactive Member Join Date: Jan 2003 Posts: 43,524	Quote: Originally Posted by IvanIV Apparently one or more cores should be low power consumption low performance, which is enough for background processing when phone is in standby. When more intensive tasks are running the other cores are used instead. Fo shizzle. If they are designed that way. In general though....

16-01-2013, 19:35	#16
PencilBreath Forum Member Join Date: Dec 2010 Location: Here. Posts: 3,345	Quote: Originally Posted by red_g00ner The next gen multi-cores should have better battery life from what l read a while back. Essentially you will have the normal quad cores and then a fifth slower core, so that when your not using the phone, i.e. in standby, everything switches to the 5 low power/slower one I thought modern cores park when not in use so is that not the same?

16-01-2013, 19:44	#17
whoever,hey Forum Member Join Date: Mar 2006 Posts: 30,072	Quote: Originally Posted by PencilBreath I thought modern cores park when not in use so is that not the same? The last time i heard the term 'park' was in parking the head of a HDD .

16-01-2013, 20:05	#18
PencilBreath Forum Member Join Date: Dec 2010 Location: Here. Posts: 3,345	http://i53.photobucket.com/albums/g6...ps3779be62.png https://www.google.co.uk/search?q=Co...ient=firefox-a Perhaps it's just a windows feature.

16-01-2013, 20:18	#19
flagpole Inactive Member Join Date: Jan 2003 Posts: 43,524	I've never heard of it either. In that picture it looks to be the virtual/hyperthreaded cores that are parked.

16-01-2013, 20:25	#20
Gormond Forum Member Join Date: Jul 2006 Location: Scotland Posts: 15,714	Quote: Originally Posted by PencilBreath http://i53.photobucket.com/albums/g6...ps3779be62.png https://www.google.co.uk/search?q=Co...ient=firefox-a Perhaps it's just a windows feature. I think you are getting confused, only threads can be parked not cores. Although when idle CPUs don't consume much power any way.

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Multi core phone CPUs