What's the point in e cores?

[Drystoner]

I understand that e cores are supposed to help with background processes like the OS and other recording applications, but why not just add more regular cores?

These e cores are never used in gaming, are not as fast as regular cores, so I don't see the point?

Surely just adding more p cores will be better at this job? And I think that's the difference we are seeing with Intel and AMD right now. AMD are sticking with lots of regular cores multithreading, and adding more cache. To me that makes more sense for gamers than the direction Intel is taking.

[Omega]

Origineel geplaatst door Stacked:

I've also noticed my OS to be snappier and smoother with more cores. So it appears things like your OS does scale with cores, at least for W11.

So with intel, they can assign important processes to your e cores leaving your p cores to do the gaming or tasks where you want to squeeze as much single threading or performance out your regular cores as possible.

That being said if I were buying a CPU today whether it's from Intel or AMD. I'd make sure it has 8 regular cores. Consoles have 8 proper zen 3 cores now so it makes sense to match that amount. The e cores are just there to help with the OS. I believe Xbox OS and probably PlayStation assign a core for the OS.

The PS4 specifically has an interesting solution to this problem.

It had a seperate low-power ARM-based CPU for the system and background tasks. But it still had a seperate core reserved for the system, my best guess is that it was used for the streaming feature and maybe the decompression of downloads.

[Agent]

Origineel geplaatst door Omega:

Origineel geplaatst door Stacked:

I've also noticed my OS to be snappier and smoother with more cores. So it appears things like your OS does scale with cores, at least for W11.

So with intel, they can assign important processes to your e cores leaving your p cores to do the gaming or tasks where you want to squeeze as much single threading or performance out your regular cores as possible.

That being said if I were buying a CPU today whether it's from Intel or AMD. I'd make sure it has 8 regular cores. Consoles have 8 proper zen 3 cores now so it makes sense to match that amount. The e cores are just there to help with the OS. I believe Xbox OS and probably PlayStation assign a core for the OS.

The PS4 specifically has an interesting solution to this problem.

It had a seperate low-power ARM-based CPU for the system and background tasks. But it still had a seperate core reserved for the system, my best guess is that it was used for the streaming feature and maybe the decompression of downloads.

Never knew about that. I guess they were thinking ahead with that one.

[Illusion of Progress]

Origineel geplaatst door Nebsun:

If I am going to make my cpu do some work, I want it to work at maximum power.
Sure e-cores might sound nice for "background" tasks - but really... what is my OS doing in the background that it needs dedicated cores ??
I would rather get an extra p-core than 4 e-cores.

What are you doing though?

Stuff that parallelizes highly? Then those 4 e-cores will yield better performance than 1 p-core.

Not utilizing all your cores? Then... you clearly have enough, no?

So in what use-case would the extra cores being p-cores be better? They exist, but the only ones I can really think of falls under "running a lot of low threaded stuff concurrently". And such uses cases exist but probably aren't as common for at home consumers especially. If you're in such a use use case, then a Ryzen 9, Threadripper, or whatever Intel has going on at the top like a Xeron might be for you (though this still works against you in all but the first example as you're giving up per core performance for the extra cores).

And the e-cores are still far better than nothing there even in those use-cases. It's benefit most of the time and a slight drawback a slim minority of the time. Yes there are examples where all p-cores might be better but there are far more where the e-cores are better. They went with the more commonly better one.

[PopinFRESH]

Origineel geplaatst door Nebsun:

Origineel geplaatst door Illusion of Progress:

People like to compare the e-cores to p-cores 1:1 and then they get hung up on "but I'm getting lesser cores" but back in reality, it doesn't work that way. Space is a factor that needs to be accommodated for, and once you do that, the e-cores look more promising. They never move on to realizing the collective power can actually be higher because they're stuck on looking at them 1:1.

If I am going to make my cpu do some work, I want it to work at maximum power.
Sure e-cores might sound nice for "background" tasks - but really... what is my OS doing in the background that it needs dedicated cores ??
I would rather get an extra p-core than 4 e-cores.

You're again ignoring all other constraints. Why would you want another p-core rather than 4x e-cores if that swap means all of the other p-cores have to run a bit slower? Would you make this same argument and disable SMT to remove context switching?; even though 2-way SMT will likely yield about 30% better performance with concurrency? Did you make this same argument back when the Pentium D was launched? "Why not have a higher clock'd single core instead of putting two slower cores on the CPU"?

[_I_]

but each e cores is about 75% the performance of the p core

each e core looks to have its own cache, p core has 2 threads with shared cache

if its like moving multiple boxes, you dont need to count the idle return time
4 e cores could do the work faster than the single p core, as long as the scheduler/manager saves the heavy/priority boxes for the p cores/threads all is good

but thats alot of windows making poor decisions on how to make the os optimized for new hardware

games do like core performance over more cores, so hopefully the os knows to put their work on the p cores not e cores
which is why disabling e cores for gaming is better overall

[N3tRunn3r]

Back in the days OS'es were built upon Hardware stuff, and nowadays Hardware becomes adjusted and adpated to OS'es, also to maintain better security and stability.

The one hand washes the other ..

[Illusion of Progress]

Origineel geplaatst door _I_:

each e core looks to have its own cache, p core has 2 threads with shared cache

The e-cores share L2 cache among a cluster of 4. In a way, think of the e-core clusters as a CCD on AMD's side in that they typically come in a given grouped amount. AMD's CCDs are 8 cores (since Ryzen 3000). Intel's e-cores are currently clusters of four. That's why you find them in multiples of four so often (not positive if they always are but they seem to mostly be, and I'd presume non-multiples of four are partially defective e-cores), and it's why the Core i7 14700 is adding four e-cores from its predecessor's total (and going from 8 to 12 total).

The p-cores have dedicated L2 cache (the extra logical "core" from Hyper-threading isn't an actual core so of course it will share L2 cache with its parent core).

[PopinFRESH]

Origineel geplaatst door Omega:

Origineel geplaatst door Stacked:

I've also noticed my OS to be snappier and smoother with more cores. So it appears things like your OS does scale with cores, at least for W11.

So with intel, they can assign important processes to your e cores leaving your p cores to do the gaming or tasks where you want to squeeze as much single threading or performance out your regular cores as possible.

That being said if I were buying a CPU today whether it's from Intel or AMD. I'd make sure it has 8 regular cores. Consoles have 8 proper zen 3 cores now so it makes sense to match that amount. The e cores are just there to help with the OS. I believe Xbox OS and probably PlayStation assign a core for the OS.

The PS4 specifically has an interesting solution to this problem.

It had a seperate low-power ARM-based CPU for the system and background tasks. But it still had a seperate core reserved for the system, my best guess is that it was used for the streaming feature and maybe the decompression of downloads.

You're misinformed regarding the PS4. It does not have a separate ARM CPU for the OS and background tasks. You are either misunderstanding how AMD was planning to incorporate Cortex-A5 within their APUs back in 2013; or you are referring to the plethora of people who mistakenly thought the CXD90025G chip and its associated Samsung DDR3 SRAM module were a separate ARM CPU. That chip and the memory module is the PS4s network processor.

https://gamingbolt.com/wp-content/uploads/2013/11/LR_41.jpg

The AMD integrating an ARM CPU in their APUs headlines were largely mistaken as to what AMD was doing. They have an integrated processor which as far as I know for all of the Zen CPUs is based on an ARM design. This is the PSP which is similar in nature to Intel's "Management Engine" and is used for things like their fTMP functionality, their secure memory features, etc. However, this is not a separate ARM CPU that is exposed to the OS to run the OS and background tasks like you're suggesting is the case with the PS4.

[_I_]

yep, that sounds more like it
that is the ps4 sb

when the ps4 is in 'standby' mode its not really off, its just in a lower power idle stale and can update and keep usb powered without running the display and ui, waiting for bt or other input to turn it fully on

[Bad 💀 Motha]

PS4 uses an AMD Jaguar class of multi-core CPU.

None of the consoles from Nintendo, Microsoft or Sony use ARM

[PopinFRESH]

Origineel geplaatst door Bad 💀 Motha:

PS4 uses an AMD Jaguar class of multi-core CPU.

None of the consoles from Nintendo, Microsoft or Sony use ARM

Nintendo does use ARM. The Tegra X1 in the Switch is an ARM CPU.

[Guydodge]

more often than not the ecores improve performance in gaming. like always
certain games favor certain cpus.just leave them on the difference in performance
can improve massively to very little.i have never noticed any decrease.there are a few games
that get hindered slightly but you can say the same thing about intel vrs amd in various
games.

https://www.youtube.com/watch?v=LcQUUmi3rWI

[Bad 💀 Motha]

Origineel geplaatst door PopinFRESH:

Origineel geplaatst door Bad 💀 Motha:

PS4 uses an AMD Jaguar class of multi-core CPU.

None of the consoles from Nintendo, Microsoft or Sony use ARM

Nintendo does use ARM. The Tegra X1 in the Switch is an ARM CPU.

OK good to know but still; PlayStation; NO.
And I wasn't familiar with Switch cause I could care less about that junk.
Switch 2 is actually looking like it might be a hand-held power-house though; real question is though, will it have good games available and many of them.

[Bad 💀 Motha]

Origineel geplaatst door Guydodge:

more often than not the ecores improve performance in gaming. like always
certain games favor certain cpus.just leave them on the difference in performance
can improve massively to very little.i have never noticed any decrease.there are a few games
that get hindered slightly but you can say the same thing about intel vrs amd in various
games.

https://www.youtube.com/watch?v=LcQUUmi3rWI

It's not always going to be better in all games. Especially if the Game wasn't CPU-heavy to begin with. It's more noticeable in CPU-heavy games, as the E-Cores can be used to run the OS Kernel, Services and background apps and tasks while the P-Cores handles the game entirely.

Again this has many factors though; first off have to use a proper OS, such as Win11 22H2 or 22H3; not Win10. I'm not sure what Linux distros can properly handle those Core types.

[PopinFRESH]

Origineel geplaatst door Bad 💀 Motha:

Origineel geplaatst door Guydodge:

more often than not the ecores improve performance in gaming. like always
certain games favor certain cpus.just leave them on the difference in performance
can improve massively to very little.i have never noticed any decrease.there are a few games
that get hindered slightly but you can say the same thing about intel vrs amd in various
games.

https://www.youtube.com/watch?v=LcQUUmi3rWI

…Again this has many factors though; first off have to use a proper OS, such as Win11 22H2 or 22H3; not Win10. …

Wtf is 22H3? Windows versioning is based on Year followed by month or which half the year, e.g. 22H1 bein in the first half of 2022. Where is this mythical 3rd half of the year 2022?