AMD 3D V-Cache Performance Optimizer Driver Posted For Linux

[Weasel]

Sounds like a fine enough idea in theory, as long as this driver doesn’t use core parking and turn the 12/16 core X3D chips into 6/8 core ones like what AMD does on Windows and the game bar or whatever.

No it's a terrible idea. This requires the application to actually be aware of this shit and write to it. Unreal. It's not gonna happen.

[habilain]

Lol, Lmao even. Old FUD is Old.

It was vaguely true in the late 00s when 4 core configurations were common that games didn't use more than 4 threads, but ever since the PS4 generation some games will thread out to 8 cores, but most games will take as many cores as you can give them. That doesn't mean you're going to get more FPS out of it but you will get better latency as was widely examined back when AMD launched Ryzen in the first place.

I'd be interested to see which games you're referring to. Most games that utilise more than 4 threads are likely to be things like Stellaris, Civilisation etc. where FPS isn't a huge concern (which incidentally, are not particularly console focused games). But outside of loading, I think the only games on Steam's top 25 played that would benefit from more than 4 threads are Satisfactory and Football Manager, so I stand by what I said.


Oh, and a minor nitpick, but 8-core consoles do not offer 8 cores to games. One core has always been reserved for the OS, so a PS4 generation game will scale to at most 7 cores, unless additional optimisation is done.

I fail to see why 2 would be a special case when it clearly works with 12 CCDs (see Epyc 9684X).

It's not that it can't work, but it's less likely to work on consumer platforms. In a commercial setting, people make sure that they compile their applications to take full advantage of the hardware. On consumer desktop? Not as much, so having the higher frequency cores might be worthwhile in this situation. Maybe it will be worth it in the future, but not quite yet.

[pWe00Iri3e7Z9lHOX2Qx]

What was the deal with Zen 5 on Windows? I know the Zen 4 X3D chips are using core parking there. But I remember reading some Zen 5 review that mentioned it was using some driver that Zen 4 parts weren't. Was it the mobile AI SKUs due to the heterogeneous 5 / 5c cores?

I stopped being lazy and went and found it.

The AMD Ryzen 9 9950X and Ryzen 9 9900X Review: Flagship Zen 5 Soars - and Stalls (anandtech.com)

The Return of The PPM Provisioning Driver: But There's No 3D V-Cache, So Why?


Specifically relating to the Ryzen 9 9950X and the Ryzen 9 9900X, AMD has brought back their PPM Provisioning driver. The last time we saw the PPM driver was back in our Ryzen 9 7950X3D review, when AMD first introduced it alongside their first multi-CCD X3D processor. This chip was special because one (and just one) CCD came packaged with AMD's 3D V-Cache, which essentially adds a large slice of L3 cache (64 MB) on top of the existing 32 MB of L3 cache on that CCD.

The PPM driver is a fundamental element that works to ensure that the 3D V-Cache is fully utilized within games, which otherwise may inadvertently bypass the CCD with the extra cache. It works by parking the 'vanilla' CCD, so that the game is running solely on the cores from the CCD with the 3D V-Cache.

For the Ryzen 7000 generation, the PPM driver was only required on the X3D chips with multiple CCDs, such as the Ryzen 9 7950X3D. But that's not the case anymore, it seems, as AMD is deploying it for all multi-CCD Ryzen 9000 processors.

[shmerl]

I'd be interested to see which games you're referring to. Most games that utilise more than 4 threads are likely to be things like Stellaris, Civilisation etc. where FPS isn't a huge concern

It's not 2000's anymore. Any normal modern game uses a ton of threads and should be loading CPU evenly benefiting from all cores. Cyberpunk 2077 does exactly that.

[habilain]

It's not 2000's anymore. Any normal modern game uses a ton of threads and should be loading CPU evenly benefiting from all cores. Cyberpunk 2077 does exactly that.

At the risk of stating the obvious, a single game is not representative of "most games". I'm not denying that there exist games that can use more than 4 cores - I explicitly stated that, and gave some examples! However, after checking Steamdb's charts for currently played games, I am still pretty convinced that most games do not require more than 4 cores for running well.

I'll also point out that "using a ton of threads" is not optimal due to overheads (e.g. synchronisation). While there's certainly a school of though that every parallel task should be a thread and the OS should handle distribution, we're certainly not at that reality yet. This is why games typically do their own internal scheduling (e.g. look at the timer related functions in Godot; if we could just throw everything into a thread, a lot of these would not be necessary).

[Luke_Wolf]

I'd be interested to see which games you're referring to. Most games that utilise more than 4 threads are likely to be things like Stellaris, Civilisation etc. where FPS isn't a huge concern (which incidentally, are not particularly console focused games). But outside of loading, I think the only games on Steam's top 25 played that would benefit from more than 4 threads are Satisfactory and Football Manager, so I stand by what I said.

Load MangoHud up and start running games right now. It's basically everything starting from the PS4 era because game engines had to be written to be able to run on CPUs that had 8 cores but were wimpy netbook CPUs, so most games are actually very heavily threaded these days, and with the shift to Vulkan and DX12 even more so. As someone who plays things that are primarily in the FPS and RPG genres I've measured this myself back when Ryzen originally launched. You're just laughably wrong.

[Luke_Wolf]

At the risk of stating the obvious, a single game is not representative of "most games". I'm not denying that there exist games that can use more than 4 cores - I explicitly stated that, and gave some examples! However, after checking Steamdb's charts for currently played games, I am still pretty convinced that most games do not require more than 4 cores for running well.

I'll also point out that "using a ton of threads" is not optimal due to overheads (e.g. synchronisation). While there's certainly a school of though that every parallel task should be a thread and the OS should handle distribution, we're certainly not at that reality yet. This is why games typically do their own internal scheduling (e.g. look at the timer related functions in Godot; if we could just throw everything into a thread, a lot of these would not be necessary).

Go back and watch the original Ryzen review videos, even though the 8 core Ryzen wasn't getting "MOAR FRAMEZ" against the 4 core intel counterpart at the time most reviewers noticed the decrease in stuttering and latency making for a better gaming experience.

[shmerl]

At the risk of stating the obvious, a single game is not representative of "most games". I'm not denying that there exist games that can use more than 4 cores - I explicitly stated that, and gave some examples! However, after checking Steamdb's charts for currently played games, I am still pretty convinced that most games do not require more than 4 cores for running well.

I said normal. If some game can't use CPU properly - it's not normal.

[Luke_Wolf]

I said normal. If some game can't use CPU properly - it's not normal.

To add to that most of the games that have CPU related performance problems like Bethesda games are known to have a heavy main thread rather than spreading out the work in a relatively even fashion.

Thread Pools (which are used to do this even spreading) that default scale to your available cores have also been around for a very long time.

[entropicdrifter]

Finding myself genuinely hyped for this driver. Upgraded to a 7800X3D this past summer and I'm hoping this will boost my gaming performance by quite a bit. I suppose in the meantime I could do core parking when gamemode is used or something like that.

EDIT: Nevermind, I forgot that the 7800X3D only has one CCD, so all cores have access to the massive cache. Still, nice to see AMD following up and trying to optimize their Linux performance, even if it did come much later than the Windows drivers