RT perf in Metro Exodus EE for RDNA2 is really good, but gimped by HairWorks.

1 : Anonymous2021/05/08 01:17 ID: n7e0gn

A few tech guys on twitter running benches on the new enhanced edition release to test ray tracing perf uncovered something that we used to see in the old days.

Remember when HairWorks would force tessellation factors of 64x for no visual benefit, just to neuter perf on AMD GPUs as they were weaker on tessellation?

Now its happening but with RT.



HairWorks literally destroys performance/frame times in this scene.

Looks like a nasty case of a billion triangles on HairWorks + RT triangle intersection overload.

I suspect HairWorks does not get a simplified geometry model into the BVH acceleration structure like everything else. It retails the full triangle load within the AS, so each ray has to test against an excessive volume of triangles within a small area of a BVH.

Besides these, it appears that 4A Games did a great job optimizing RT performance on RDNA2 GPUs.

GPU profiling for more info:

It seems like they are basically doing everything right in terms of RT. Occupancy's very good, TONS of async compute, RT is done with Inline-RT (as far as I can tell right now). It's extremely impressive.

I have been saying that RDNA2 would do well with RT when using DXR1.1, with the feature MS added with AMD collaboration on the new consoles, for inline RT (a more optimized method of casting rays & especially for extra bounces or long ray distance).

This is what 4A Games used to ensure RT performs well for the release of the game on these new RDNA2 consoles.

Yet NV sponsored the Metro series and they obviously snuck in their HairWorks that throws a wrench into the RT pipeline.

2 : Anonymous2021/05/08 02:35 ID: gxcignx

Couldn't AMD force the Tesselation to 16x max as default for every game?

ID: gxdeqvn

Yeah it's an option in the drivers already

3 : Anonymous2021/05/08 01:52 ID: gxcdtz7

Wow I was just about to enable this setting and decided against it on my 6800xt.

I couldn’t find anything online a few hours ago, but great timing. Thanks!

ID: gxd8tn6

This is not news, HairWorks has been around since Witcher 3 times and it's a known exclusive Nvidia accelerate feature. Nobody with AMD should use it, as nobody with AMD should use PhysX. Such PSAs have no relevance and people who just use presets "all sliders to the right" are tools.

ID: gxdcck5

But "all sliders to the right" at 1440p gives me ~80 fps in my 6900XT which is good enough. Buf yeah, these slides are not worth the perf hit in general with weaker cards.

ID: gxdrd98

Errr, Phsyx is an open source (For PC, not consoles) physics engine these days. it's used in a large amount of games, it's the built in physics engine for Unity and Unreal Engine and primarily runs on the CPU these days where Nvidia vs AMD doesn't even come into it.

If you're talking about hardware accelerated PhysX then you have to go back a while to find a game that actually uses it, even the latest games on the wiki page for tracking it don't show a hardware accelerated PhysX flag when inspected. I'm pretty sure hardware accelerated PhysX is dead these days.

ID: gxe9m51

I don't even bother turning hairworks on for a nvidia gpu it normally tanks the fps for any card you use.

4 : Anonymous2021/05/08 01:32 ID: gxcbru2

We're going to need HUB to include this in their editorial direction.

ID: gxceza1

Yeah, would also see if HUB or other tech reviewers can repeat these tests.

ID: gxciglp

The AMD drivers have a tesselation setting that can be lowered right down to 4x. I'm surprised no one has tested that to see if the performance goes up.

ID: gxcuxtf

He was joking FYI. Lol.

5 : Anonymous2021/05/08 10:22 ID: gxdh4ew

ITT sour grapes

6 : Anonymous2021/05/08 07:34 ID: gxd6x2q

Maybe they just discovered that having a simplified version of the hair in the acceleration structure led to unacceptable visual glitches?

ID: gxdhshw

No don't you see, 4A games hate

and so they make their games inefficient and bad.
, for when you want to feel like a victim

7 : Anonymous2021/05/08 12:33 ID: gxdqr5h

Is there no way to disable hair works?

ID: gxdrkn6

It's off by default. "I intentionally hit my balls with a hammer and now it hurts! It's an Nvidia conspiracy!11"

ID: gxdsr9k

Why would you use hairworks on anything? I remember when witcher 3 first came out. I had a 970 at the time. It made the game basically unplayable, so even though i had a Nvidia card the feature couldn't be used. I've stayed away from it ever since.

9 : Anonymous2021/05/08 21:54 ID: gxfjs80

At least you can turn it off. Anyone remember the Crysis 2 invisible tesselated ocean debacle?

10 : Anonymous2021/05/08 23:44 ID: gxfwfzw

That was fake news through and through.

The ocean under the map was never tessellated during gameplay. It was culled. Wireframe mode specifically disables culling since it's meant to show everything.

11 : Anonymous2021/05/08 06:38 ID: gxd3al6

Wouldn't they mind now look into valhalla performance to find what amd did to gimp nvidia cards and not just in few scenes with certain graphics settings, but for the whole game.

12 : Anonymous2021/05/08 07:30 ID: gxd6o50

AMD doesn't have any black box technology for game developers (AFAIK), so it is really up to the devs, but still worth looking into.

13 : Anonymous2021/05/08 08:03 ID: gxd8qr1

Nothing, the answer to this is literally nothing. NVIDIA's drivers are garbage and have a massive overhead, every time in Valhalla you have a wealth of draw calls the CPU chugs. Not to say it never happened (Tomb Raider Tress FX) but this case is literally NVIDIA gimping NVIDIA.

14 : Anonymous2021/05/08 06:06 ID: gxd129v

This makes me worried for The Witcher 3's raytracing update then. It had a hairworks issue back when it launched and by the sounds of this we're probably going to be repeating history again...

15 : Anonymous2021/05/08 08:10 ID: gxd965e

HairWorks can be turned on in both Witcher and in Metro. It's off by default in both. I have absolutely no worries about the morons who will enable it on AMD cards.

16 : Anonymous2021/05/08 08:16 ID: gxd9k78

As someone just trying Metro's new update on a 6800xt @ 3440x1440p, it makes no difference. My game can't get higher than 35fps even with the latest AMD update, with tessellation disabled, etc.

Game is either broken which is highly likely since I saw someone with a 6900xt pulling over double my fps at 2560x1440p on slightly higher settings (extreme, I was using ultra) or something else is going on. GPU use is 100% though so I dunno..

17 : Anonymous2021/05/08 08:24 ID: gxda0zt

NV: "Hey A4 you're doing too good a job in making RT good in Big Navi, we meant make it an RT showcase FOR US"

A4: But but, optimizing for several platforms is our job so our customers are happy!

NV: "m8 we paid for metric tons of marketing for this and several million copies of the game for bundles, do as I say, or else..."

18 : Anonymous2021/05/08 12:52 ID: gxdsg6f

Hairworks is an optional Nvidia feature that is turned off by default. Stop blaming the game or "big company bad" because you turn on a vendor-specific feature on a GPU made by the other company.

19 : Anonymous2021/05/08 04:04 ID: gxcr7m6


20 : Anonymous2021/05/08 05:03 ID: gxcwd7q

Ehh this isn't true. Vega, RDNA1 and 2 are Tessellation monsters and if its just hair works, they tank through it.

21 : Anonymous2021/05/08 05:24 ID: gxcy04n

The problem is not hairworks itself as AMD cards can do absurd tessellation on par or better than Nvidia this problem is born from the nature of the tech combined with ray tracing so only fix is excluding it from RT.

22 : Anonymous2021/05/08 07:28 ID: gxd6jr5

Or creating the BVH structure for the hair too.

23 : Anonymous2021/05/08 07:36 ID: gxd73ln

So the stance here is that Nvidia should change their own tech because it's unfair towards amd? Wow, both are huge corporates that don't give a damn about the consumer as long as they buy their products.

24 : Anonymous2021/05/08 08:28 ID: gxda9i4

That's all fine and good, but won't help when all the benchmarking sites test with it on when they test with ultra settings.

25 : Anonymous2021/05/08 15:18 ID: gxe825e

Ultra preset doesn't even turn hair works on though? The fortunate thing about it is it only applies to certain creatures anyways. So taiga with that stupid giant bear that has a boatload of fur. I must admit, the fur does look badass compared to without hairworks, but the performance hit is super high on everything not just AMD.

26 : Anonymous2021/05/08 07:33 ID: gxd6wdv

Nvidia gimping amd with hair works... Nothing amd would ever do in amd sponsored implementations...

27 : Anonymous2021/05/08 10:16 ID: gxdgqjb

literally all of AMD’s current solutions are open source and are vendor agnostic.

28 : Anonymous2021/05/08 12:57 ID: gxdstuz

Hairworks has been open-source since 2016 and does not require Nvidia hardware to run.

29 : Anonymous2021/05/08 10:20 ID: gxdh11r

RDNA is still shit at tessellation. news at 11

| Remember when HairWorks would force tessellation factors of 64x for no visual benefit

This was never true, and the reduced tessellation factors you could force through amd's shitty control panel massively reduced the visual quality (especially in witcher 3) and caused serious jank and glitches.

There is no conspiracy, your victim complex is ridiculous

30 : Anonymous2021/05/08 11:11 ID: gxdkbi0

You obviously don't know your history.

CDPR went out of their way to reverse engineer HairWorks libraries to add in the support for custom tessellation factors in further updates to precisely address the crap performance. They changed the default from x64 to x32, and added sliders allowing users to reduce it to x16 or x8. Visual artifacts appeared at x8 so it was not recommended.

It was because the tech community raised the issue back then and it made it into the tech press that HairWorks was destroying perf, that CDPR did that to the benefit of ALL gamers, AMD OR NV users.

31 : Anonymous2021/05/08 01:36 ID: gxcc7cp


32 : Anonymous2021/05/08 02:17 ID: gxcghj6

the numbers are right there in the links above

33 : Anonymous2021/05/08 02:01 ID: gxceugs


34 : Anonymous2021/05/08 07:39 ID: gxd78n8

You need to proof that they purposely gimped it. And still then it's normal business practicess performed by every side. Amd is doing everything Intel and Nvidia are doing as well. They aren't a 'better' company. They don't care about the customer any more then any other company. The numbers are the only thing that count.

35 : Anonymous2021/05/08 09:27 ID: gxdds3y

If you make claims like

Remember when HairWorks would force tessellation factors of 64x for no visual benefit, just to neuter perf on AMD GPUs as they were weaker on tessellation?

Now its happening but with RT.

you have to present proof that this is done purposefully. If you have no proof, then you're just making stuff up. Which, of course, wouldn't be the first time for you.

Get off the conspiracy train, Phobo, it's not good for you.

36 : Anonymous2021/05/08 02:33 ID: gxcia0z

Exactly, the fact that you're forced to use hairworks on amd gpu's proves Nvidia is actively trying to gimp... Oh right, you don't have to turn it on. Or you could just force the tessellation factor via adrenalin. Nvidia does shady shit all the time, like with Project cars way back when, on the other hand this is just drama for the sake of drama.

37 : Anonymous2021/05/08 08:17 ID: gxd9l9b

Nvidia is really awesome, not at all a company made by a child...

38 : Anonymous2021/05/08 04:48 ID: gxcv5yk

Then turn off hairworks. PROBLEM SOLVED! Its always AMD = VICTIM, NVIDIA = BAD.

39 : Anonymous2021/05/08 20:10 ID: gxf7kli

there definitely few individuals with a victim mentality that's for sure.

40 : Anonymous2021/05/08 15:22 ID: gxe8lb5

Errr no. It's not hairworks. Wake up and smell the coffee fanboys. Nvidia has better RT period. They have 2 years lead on AMD and it shows. Same with DLSS.

41 : Anonymous2021/05/08 12:13 ID: gxdp1mr

This is precisely why I won't consider ever buying an Nvidia product at this point in time. Their company culture is to project the idea that they are the performance leader by making a superior product, when in reality they do unethical things like this (one thing in a very long list of unethical things) instead of competing on the merits of a great product at a fair price.

Edit: Found the Nvidia fan boys... lol

42 : Anonymous2021/05/08 06:59 ID: gxd4qxj

Current AMD gpus are aa fast or even faster than Nvidia at actual geometry in games and Tessellation.

The problem is not Tessellation. The problem is hairworks adding to the BVH structure of RT.

43 : Anonymous2021/05/08 07:09 ID: gxd5eh1

And my question is: why is that a problem when it's going to "gimp" performance on both sides? Has anyone actually tested the same exact same scene with a 3080 before throwing accusations?

44 : Anonymous2021/05/08 09:11 ID: gxdctc9

This is classic Phobochai. Throwing fuel to the amd fanboy fire just for the fuck of it.

45 : Anonymous2021/05/08 11:08 ID: gxdk5ar

You are free to disagree with me. You're not free to constantly get personal with your vendetta. I have not burned your house, or killed your dog.

If you hate me, fair enough. But don't hate me so much that you have to shitpost when people actually are having a discussion.

Also, I bring this here because of great discussion on the tech twitter that I thought this sub could also contribute further.

46 : Anonymous2021/05/08 18:42 ID: gxex3n8

It's funny how AMD hardware conveniently runs worse in Nvidia sponsored games, but Nvidia cards do just fine in AMD sponsored games.

Oh GEE I wonder WHY??

47 : Anonymous2021/05/08 10:05 ID: gxdg45p

just set tessellation to 16x or 32x(your taste, your choice) max on radeon settings(control panel)

48 : Anonymous2021/05/08 11:29 ID: gxdlm1h

/comments/mq81c9/whichever_wins_you_lose_gpu_wars/" class="reddit-press-link" target="_blank" rel="noopener">https://www.reddit.com//comments/mq81c9/whichever_wins_you_lose_gpu_wars/

49 : Anonymous2021/05/08 13:45 ID: gxdxkxd

Does the AMD optimized tessellation mode in the driver not work? It exists for this exact reason, to limit tessellation.

50 : Anonymous2021/05/08 06:16 ID: gxd1qpu

Can someone provide config files of that game? someone can see to check if hairworks can be disabled through there

51 : Anonymous2021/05/08 08:40 ID: gxdazot

It's an option in the game video settings.


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