So, Decent Analysis from AMD's Reddit on the gaming latency issues

Zion Halcyon

Zion Halcyon

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Causes of poor gaming relative to CPU performance of Ryzen:

1. Windows is load-balancing across CCXes. This means that a thread is being moved around on the CPU - which is normal - so that a single core isn't used more than others. On Ryzen, that needs to happen ONLY within a CCX, otherwise you will incur a massive penalty when that thread no longer finds its data in the caches of the CCX.

2. SMT hurts single threaded performance due to shared structure. Ryzen statically partitions three structures to support SMT: Micro-op queue (dispatcher), Retirement queue, Store queue. This means that, with SMT enabled, these resources are cut, potentially, in HALF (mind you, these are just queues that impact throughput of a single thread).

3. Memory latency quirks still not worked out. Gaming can be quite sensitive to memory latency and bandwidth. These issues will be, most likely, remedied with BIOS updates.

Combined you can see, clearly, what is happening and most of the reviews make sense.

A Windows driver update to treat each CCX almost as if it were its own CPU will help immensely. The SMT problem is likely PERMANENT... unless AMD can adjust the partitioning with microcode, which I doubt.

What this all means is simple: once the Windows update has landed, BIOSes are patched up, and SMT is disabled, an 8-core Ryzen will likely be competitive with a quad i7 in gaming while blowing past it in multi-threaded. If all you do is game, then the 1700 may well become a very valid option that will work increasingly better in future games.
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SMT issue will be managed with individual game engines by companies that reach out to AMD and get them patched. So I expect no patches for old games and probable patches for most current AAA titles.
 
Except Bethesda. They stated they will optimize all their games.


Simplyfun said:
SMT issue will be managed with individual game engines by companies that reach out to AMD and get them patched. So I expect no patches for old games and probable patches for most current AAA titles.
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wishful thinking, but I look forward to these optimizations and success of Ryzen (knowing that it just needs to compete, not win the race, in gaming)
 
TLDR: In the future it will be great! :rolleyes:

I'll give them a chance, but I'm not holding my breath based on the "recommendations" from AMD to reviewers.
 
This is good news, just too bad it couldn't have been identified a couple months ago to have the Windows and BIOS updates ready for launch day. The real question is how soon will we see the fixes?

Of course, I hope that no one thinks that with these fixes that Ryzen will "blow away" the 7700K in gaming. Seems like that's what people were hoping for on launch day, when just a couple months ago the consensus was "if it's within 10% performance of haswell, it will be a huge win!" Ryzen is behind in single-threaded performance, and so even with the fixes, we shouldn't expect a sudden overtaking at gaming FPS. However, newer games, if coded properly, could make it perform in the games similarly to productivity. I'm not sure if that is all that realistic, given the requirement for games, vs the requirements for the various productivity tools.

While these issues look like they can be resolved and make Ryzen a decent gaming processor, the poor performance out of the box in gaming is going to sour many people. Too many people in gaming never take a second look at a product - if it gets bad press once, the issue is repeated as fact even well after the issue has been resolved. How many people are still staying they'll stay away from AMD GPU's because they have "horrible drivers" - a situation that hasn't been the case for many years now.
 
Definitely good news and nice to see AMD release a solid competitive part.
 
1 is very similar to NUMA which Windows already does so it probably needs not that much work to get it accomplished.
2 is a bit weird as it would imply they slow down due to the size of the queue being too small when halved. If so shoot whoever designed the queue as that would have not been expensive to fix. Yet the performance during heavy multithreading suggest this is unlikely to be the cause.
3 is a bit worrying but let's hope it is lack of platform maturity and hence BIOS fixable

Wish I had a Ryzen box to play with in order to see what pinning processes to cores results in. Bit annoying to do manually but if it works plenty of tools that can do it for you.
 
Zion Halcyon said:
What this all means is simple: once the Windows update has landed, BIOSes are patched up, and SMT is disabled, an 8-core Ryzen will likely be competitive with a quad i7 in gaming while blowing past it in multi-threaded. If all you do is game, then the 1700 may well become a very valid option that will work increasingly better in future games.
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Likely? Ehhhhh...
 
The "future games will use more cores" argument is highly retarded. This started back in 2011, I think or before that? Games don't need to use more cores and I think this CPU performs just fine in games
 
The public image damage has been done when reviewers go retard for page hits. It's like all of a sudden no one expected teething issues on a brand new platform that is competing with a well aged and very optimized long standing platform. smh
 
thesmokingman said:
The public image damage has been done when reviewers go retard for page hits. It's like all of a sudden no one expected teething issues on a brand new platform that is competing with a well aged and very optimized long standing platform. smh
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I don't think it's that big of a deal. Lots of people apparently wanted to pay the early adopter's tax. The rest of us get to see how things play out as usual and anyone who bought a 6700/7700K recently won't care either way.
 
Furious_Styles said:
I don't think it's that big of a deal. Lots of people apparently wanted to pay the early adopter's tax. The rest of us get to see how things play out as usual and anyone who bought a 6700/7700K recently won't care either way.
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It is obviously a huge deal as their stock is tanking because even reviewers cannot get their heads out of their asses and realize that yea, brand spanking new product didn't exceed a metric/expectation they created, therefor it sucks in gaming while ignoring that it is a brand spanking wholly new design.
 
thesmokingman said:
It is obviously a huge deal as their stock is tanking because even reviewers cannot get their heads out of their asses and realize that yea, brand spanking new product didn't exceed a metric/expectation they created, therefor it sucks in gaming while ignoring that it is a brand spanking wholly new design.
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And more and more excuses for AMD. Don't you guys get tired of it at some point?
 
thesmokingman said:
It is obviously a huge deal as their stock is tanking because even reviewers cannot get their heads out of their asses and realize that yea, brand spanking new product didn't exceed a metric/expectation they created, therefor it sucks in gaming while ignoring that it is a brand spanking wholly new design.
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It's not really tanking. And please recall the stock is up like something insane over the past year (400%)? So a little correction is nothing to worry about.
 
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Zion Halcyon said:
[link]

Causes of poor gaming relative to CPU performance of Ryzen:

1. Windows is load-balancing across CCXes. This means that a thread is being moved around on the CPU - which is normal - so that a single core isn't used more than others. On Ryzen, that needs to happen ONLY within a CCX, otherwise you will incur a massive penalty when that thread no longer finds its data in the caches of the CCX.

2. SMT hurts single threaded performance due to shared structure. Ryzen statically partitions three structures to support SMT: Micro-op queue (dispatcher), Retirement queue, Store queue. This means that, with SMT enabled, these resources are cut, potentially, in HALF (mind you, these are just queues that impact throughput of a single thread).

3. Memory latency quirks still not worked out. Gaming can be quite sensitive to memory latency and bandwidth. These issues will be, most likely, remedied with BIOS updates.

Combined you can see, clearly, what is happening and most of the reviews make sense.

A Windows driver update to treat each CCX almost as if it were its own CPU will help immensely. The SMT problem is likely PERMANENT... unless AMD can adjust the partitioning with microcode, which I doubt.

What this all means is simple: once the Windows update has landed, BIOSes are patched up, and SMT is disabled, an 8-core Ryzen will likely be competitive with a quad i7 in gaming while blowing past it in multi-threaded. If all you do is game, then the 1700 may well become a very valid option that will work increasingly better in future games.
​
Click to expand...

It might help but the conclusion of it being competitive is like pulling a rabbit out of a hat.
Software or bios problems can be remedied but that does not make up for a huge loss , the memory latency problem however is a concern for 1080p as I understand it.

-Strelok- said:
And more and more excuses for AMD. Don't you guys get tired of it at some point?
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Not as tiring as the people posting off topic remarks without contributing in any way to a thread they do not care for anyway.
 
Pieter3dnow said:
It might help but the conclusion of it being competitive is like pulling a rabbit out of a hat.
Software or bios problems can be remedied but that does not make up for a huge loss , the memory latency problem however is a concern for 1080p as I understand it.


Not as tired as the people posting off topic remarks without contributing in any way to a thread they do not care for anyway.
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So because I'm not going "OMG BEST THING SINCE SLICED BREAD" I don't care about it? Unlike you, I don't gloss over the negative aspects and hope for something in the future (DX12/Vulkan) to make up for it. We've seen it before, Bulldozer was the same shit. "Oh it'll be better in the future", and it wasn't. The difference here is that Ryzen actually has potential which IMO is good.


thesmokingman said:
See, exactly the attitude I'm describing.
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People not making excuses for everything a company does wrong? Ok, I'll let you live in the fairy world where everything is great and there are unicorns (y)
 
thesmokingman said:
It is obviously a huge deal as their stock is tanking because even reviewers cannot get their heads out of their asses and realize that yea, brand spanking new product didn't exceed a metric/expectation they created, therefor it sucks in gaming while ignoring that it is a brand spanking wholly new design.
Click to expand...


AMD should not have waited for reviewers to crash into these problems before talking about them.
 
-Strelok- said:
So because I'm not going "OMG BEST THING SINCE SLICED BREAD" I don't care about it? Unlike you, I don't gloss over the negative aspects and hope for something in the future (DX12/Vulkan) to make up for it. We've seen it before, Bulldozer was the same shit. "Oh it'll be better in the future", and it wasn't. The difference here is that Ryzen actually has potential which IMO is good.
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Already caught you in one off topic remark now you are making another. The topic is:
So, Decent Analysis from AMD's Reddit on the gaming latency issues

Do you have anything to add to this ?
Maybe you can contribute ?
Or just try and derail the topic , mods here do not mind that ....
 
FunYun said:
AMD should not have waited for reviewers to crash into these problems before talking about them.
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Fair point, but how do you know they didn't already talk about it and how would they have countered the issues from their position? Wait until the landscape of developers gets the memo? That could take forever. I suppose the issue with windows is that they could have tackled before release but we don't know any specifics. They should have been more prepared and tempered expectations.
 
IPC is there. Some games clearly are not handling it right. If every game was horrible at 1080p I would be worried. If you read the reviews that is not the case. I am sure his will be remedied down the line where in those games they find tweaks to load balance the threads correctly. We will see but no doubt the ipc is there in Zen. It blew past my expectations in that regard.
 
The irony is that AMD was harping so hard on "True Quadcore" back in the Phenom days, now they can't claim to be a true 8 core , and it's what is hurting them :p
 
Shintai said:
FX users still wait for their fixes. Any day now.
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This is true - I've built a lot of PC's (more than 200) and built maybe a dozen with FX cpu's and 965BE's. Only those computers tended to have little quirks like crashing for no reason even at stock clocks with no way to fix it. Some of the Ryzen reviews show that Ryzen/AM4 platforms are also plagued with this kind of problem. Maybe they will fix it, but I'm not going to buy a platform that still doesn't have quirks like this worked out. For now I'm turning my attention towards LGA2066 :D Maybe in the meantime if AM4 gets its kinds worked out I'll reconsider.
 
sover said:
What? The Ryzen isn't a single die?
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I'm, not 100% sure, but I believe it is all on one die. I think Zen is made up of quad core modules, much like Bulldozer was made up of dualcore Bulldozer modules. That doesnt mean they are on separate dies. It's just a design consideration, so that when they scale up they can copy and paste the quad core module as many times as they need to in order to get their desired core count.

It will be interesting to see how they handle hexacore chips. Will it be two quadcore modules, each with one core disabled?
 
Zarathustra[H] said:
I'm, not 100% sure, but I believe it is all on one die. I think Zen is made up of quad core modules, much like Bulldozer was made up of dualcore Bulldozer modules. That doesnt mean they are on separate dies. It's just a design consideration, so that when they scale up they can copy and paste the quad core module as many times as they need to in order to get their desired core count.

It will be interesting to see how they handle hexacore chips. Will it be two quadcore modules, each with one core disabled?
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So true 8 core, then, unless 8 cores on a die doesn't mean 8 core any more. :alien:
 
Its two quad core CPUs on an integrated crossbar instead of connected by an external hypertransport bus.

I would be curious to see results with games affinity set to one CCX. 4 cores is plenty for one game right now since the OS and driver threads can run on the other CCX.
 
sover said:
So true 8 core, then, unless 8 cores on a die doesn't mean 8 core any more. :alien:
Click to expand...

No, it's definitely true 8 core. There are some shared resources between the 4 cores on a module, but Intel shares some resources between its cores as well. You have to with modern designs, or you'll just generate too much heat to be able to clock as high as you'd like with this many cores.

IMHO, Bulldozer was true 8 core as well. It had 8 real integer cores on it. Yes, each two core module shared a single 256bit FPU, but it was able to split itself into two 128bit FPU's to support both cores in the module when both were loaded. IMHO, that was not what was the fundamental problem with Bulldozer. If it were, disabling half of each module would have made it as fast as an Intel quad core. It didn't. There were some small performance gains by doing this, but they were tiny. The real issue with bulldozer was a combination of long pipelines, and poor branch prediction, much like Intel's Netburst designs in the P4. That, and a poor, slow cache implementation that would easily get thrashed by the many modules, and slow things down.
 
I'll believe it when I see it...right now it's just wishful thinking/hope from AMD
 
Well hurry up with these fixes. I'm already tired of waiting... haha
 
ecmaster76 said:
Its two quad core CPUs on an integrated crossbar instead of connected by an external hypertransport bus.

I would be curious to see results with games affinity set to one CCX. 4 cores is plenty for one game right now since the OS and driver threads can run on the other CCX.
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The windows scheduler must have a way of dealing with this, or dual socket systems would perform like ass as well. It must just be a matter of patching the windows scheduler to tell it to treat a Ryzen chip as if it were two quadcore CPU's in different sockets, and only to move processes between them when it absolutely needs to. This can't be a particularly involved fix.
 
and people scoffed when i said i'd wait for the bugs to get worked out...
with a new platform theres almost always issues to be worked out. i think, if you look at this objectively, AMD has done a pretty good job from the get go. its competing with the highest intel chips at a better price and giving decent gaming results too. yes not as good as the gaming focused 7700k but still plenty fast for most gamers.
 
pendragon1 said:
and people scoffed when i said i'd wait for the bugs to get worked out...
with a new platform theres almost always issues to be worked out. i think, if you look at this objectively, AMD has done a pretty good job from the get go. its competing with the highest intel chips at a better price and giving decent gaming results too. yes not as good as the gaming focused 7700k but still plenty fast for most gamers.
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Well, waiting for bugs to get worked out isn't necessary unless you plan on gaming at 1080p.
 
pendragon1 said:
and people scoffed when i said i'd wait for the bugs to get worked out...
with a new platform theres almost always issues to be worked out. i think, if you look at this objectively, AMD has done a pretty good job from the get go. its competing with the highest intel chips at a better price and giving decent gaming results too. yes not as good as the gaming focused 7700k but still plenty fast for most gamers.
Click to expand...

Yeah, what people forget is that current Intel designs have been incremental updates on top of incremental updates dating all the way back to Pentium III, and even earlier (some would say Pentium Pro in 1995. That's 22 years of incremental improvements to pretty much the same arch. Programmers have learned to optimize for the Intel way of doing things quite a lot over that time. Yes, there have been changes over time, but still very similar basics, and an evolutionary transition, rather than a revolutionary one.

Ryzen is a completely new from scratch architecture. The first one the world has seen in the consumer computing space since the introduction of Bulldozer, which in its turn was the first one the world had seen in consumer parts since, god knows. I mean, Phenom II and Phenom were K10/Stars which were based on K8/Athlon64 which was based on K7/Athlon/Duron... So the first brand new from scratch arch since the original K7/Athlon in 1999?

While all of these architectures are still x86 at their core, the implementations mean they will be optimized for differently, and it is completely to be expected that software will need to be changed to properly optimize for a new architecture.

I think AMD's long term success with Ryzen and other Zen chips will depend a lot on how successful they are at getting developer to properly optimize for them. I'm sure devs are a little annoyed, as this is more work. It's easier to properly optimize for one arch only, especially when the work has already been done incrementally over time, and each new launch from Intel only requires minor tweaks, but on the other hand, bringing this level of a CPU down in cost to where more people can own it, also has an upside for them, and what they can do in their games.
 
variant said:
Well, waiting for bugs to get worked out isn't necessary unless you plan on gaming at 1080p.
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i do game at 1080p(50" plasma). but its not just that. there are other things that need to get worked out, hardware and software wise.
 
Zarathustra[H] said:
Yeah, what people forget is that current Intel designs have been incremental updates on top of incremental updates dating all the way back to Pentium III, and even earlier (some would say Pentium Pro in 1995
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They did introduce detours with Itanium and Netburst but those both ultimately failed. Core2 can be traced back to P3 but it has had major changes at several points

More critically though I think its fair to say Intel hasn't made major changes since multi core systems became mainstream AND games began to take advantage of them.
 
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