AMD X3D series, Core Parking is kinda dumb?

[Pets4Ever]

Rather than parking the chiplet without the 3D cache, shouldn't those cores be assigned to background tasks? Parking them seems like a waste. I assume the E-cores on Intel processors don't just stop doing work whenever a game is open. Seems like the scheduler should be made smart enough to target something like a browser instance running behind the game, or perhaps non-vital windows services.

 

[ShrimpBrime]

Rather than parking the chiplet without the 3D cache, shouldn't those cores be assigned to background tasks? Parking them seems like a waste. I assume the E-cores on Intel processors don't just stop doing work whenever a game is open. Seems like the scheduler should be made smart enough to target something like a browser instance running behind the game, or perhaps non-vital windows services.

What are you talking about? The AMD processors are traditional monolithic design, doesn't have little mini e-cores at all. Has SMT only.

 

[anonuser57]

It's less a matter of stupidity on AMD's part and more on Windows. Games generally run best with all threads on the same CCD but windows had trouble with that.

 

[Pets4Ever]

What are you talking about? The AMD processors are traditional monolithic design, doesn't have little mini e-cores at all. Has SMT only.

The AMD CPUs with 12 cores, or 16 cores have two chiplets on the die. In the case of an X3D cpu with two chiplets, only one has direct access to the 3D cache. In order to prevent games from running on the cores without the 3D cache, AMD has designed a feature whereby the "wrong" chiplet gets parked during gaming. This means that they can't contribute to the running of background processes and they can't help you in games that scale past 8 cores.

I compared it to the big.LITTLE architecture in the sense that you have less optimal cores that you don't want used for a specific task (gaming). Apparently this is solved for Intel because as far as I know Intel cpus do not park ecores in games.

It's less a matter of stupidity on AMD's part and more on Windows. Games generally run best with all threads on the same CCD but windows had trouble with that.

I remember reading that the 3D cache being on one chiplet is the specific problem this was trying to fix. The CPU uses all of it's cores in non-game jobs like rendering, encoding etc

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[tabascosauz]

I remember reading that the 3D cache being on one chiplet is the specific problem this was trying to fix. The CPU uses all of it's cores in non-game jobs like rendering, encoding etc

More like putting vcache on both would just be the most useless and wasteful endeavour ever, at least before the new and fancy Fabric makes its way over from Strix Halo to make all-vcache actually useful

What are you talking about? The AMD processors are traditional monolithic design, doesn't have little mini e-cores at all. Has SMT only.

Homogenous/heterogenous might be the word you're looking for. No Ryzens are monolithic anymore except the traditional APUs (minus Strix Halo). Then again, I'm not sure Strix's setup really counts as homogenous anymore either

 

[ShrimpBrime]

More like putting vcache on both would just be the most useless and wasteful endeavour ever, at least before the new and fancy Fabric makes its way over from Strix Halo to make all-vcache actually useful



Homogenous/heterogenous might be the word you're looking for. No Ryzens are monolithic anymore except the traditional APUs (minus Strix Halo). Then again, I'm not sure Strix's setup really counts as homogenous anymore either

Ah, Yes, I see. The Intel reference kind of threw me off a bit there. Even a 9800X3D is chiplet because I/O got its own die.

Background tasks, maybe below normal priority, most of the time wont matter what core its running on. Usually these tasks wait for more important tasks. Wasn't aware core parking was a huge issue with AMD processors till now!!

Luckily, you can disable core parking.

 

[AusWolf]

1. Your second CCD won't power down when you need more than 6/8 cores.

2. Why should the second CCD power up when you need less than 6/8 cores? It's a waste of power. They're not e-cores.

 

[ShrimpBrime]

1. Your second CCD won't power down when you need more than 6/8 cores.

2. Why should the second CCD power up when you need less than 6/8 cores? It's a waste of power. They're not e-cores.

And that's about where I'm getting confused, but reading this statement below doesn't make sense.

AMD has designed a feature whereby the "wrong" chiplet gets parked during gaming. This means that they can't contribute to the running of background processes and they can't help you in games that scale past 8 cores.

But if the "wrong" chiplet, or secondary core complex chiplet is on because the game scales past 8 threads, then it would still just be a few cores parked, both chiplets active. Windows turns the cores on and off individually, I don't think there's actually an issue or I misunderstand the way he's describing it.

Let me edit: Cores is 16 threads (Per CCD). Meaning using more than 16 threads or just 8 threads 4 cores?

 

[_roman_]

That scheduller thing is still a mess. I would never claim intel does it better with those fake E-cores. It's very sad to saw changes in 6.14.8 what i remember according to that topic.

some will never understand. I say it again - and i will ignore those who do not understand. those E-cores can not execute my code. E-cores may be nice for those who run workloads which is optimised for a 486 processor. I do not run such workloads. MY code will crash any intel processor as those E-Cores are unable to execute those.

that topic is old. It pops up or is being asked quite often. e.g. those ryzen c cores with less cache and similar topics.

-- the scheduler is an operating system issue. e.g. microsoft windows 11 pro or the linux kernel itself - not the userspace.
disabling structures in a processors is just a lazy hack. regardless if it's done with closed sorce uefi or via windows software or ...

note: not all intel processors did provide all cpu instructions. this should be also considered before buying a processor. Multiplication and division instructions are very important when they are supported and used.

 

[ShrimpBrime]

some will never understand. I say it again - and i will ignore those who do not understand. those E-cores can not execute my code. E-cores may be nice for those who run workloads which is optimised for a 486 processor. I do not run such workloads. MY code will crash any intel processor as those E-Cores are unable to execute those.

Specifically and only interested in bold. Please elaborate!!

 

[Visible Noise]

MY code will crash any intel processor as those E-Cores are unable to execute those.

Bullshit.

Post your source.

AMD has designed a feature whereby the "wrong" chiplet gets parked during gaming.

Chiplets don’t get parked. Cores do.

If the wrong cores are getting parked then AMD has to fix their drivers.

 

[AusWolf]

Chiplets don’t get parked. Cores do.

Exactly.

If the wrong cores are getting parked then AMD has to fix their drivers.

How would that even be possible when cores have affinity numbers, so the best core gets the foreground task by hardware?