AMD Threadripper 2990WX 32-Core and 2950X 16-Core Review • Hacker News Board

Re: AMD Threadripper 2990WX 32-Core and 2950X 16-Core Review

#141

Post by greglindahl » Mon, Aug 13, 2018, 8:11 PM UTC

dragontamer wrote: post #137

somebodythere wrote: post #103

Earlier quoted context omitted.

If AMD's method scales so much easier, why didn't Intel just... do that? Honest question.

Intel could do that. But AMD came out with this method first. AMD has only been doing this "infinity fabric" thing for a year. Intel was caught with their pants down. It seems like Intel is researching chiplet technology and trying to recreate AMD's success here. It takes several years to create chips. So Intel realistically won't be able to copy the strategy until 2020 or later. But you better bet that Intel is goin…

AMD introduced HyperTransport in 2001.

Re: AMD Threadripper 2990WX 32-Core and 2950X 16-Core Review

#142

Post by philwelch » Mon, Aug 13, 2018, 8:24 PM UTC

Filligree wrote: post #13

The biggest benefit I've found to running a 1950X isn't something I would have expected, but which perhaps I should have. True, it's much faster than my old system for batch processing, but most of the time it's still idle. Even if it's running Chrome flat-out, as far as the 1950X is concerned, that's idle. Because the two NUMA nodes are ~entirely independent, it's capable of running two independent processes at full…

One instance of this might be "running a performance-intensive game fullscreen on one virtual desktop while having a browser open to read strategy guides on another virtual desktop". This is a common use case for me that also seems to be the first place where performance starts to diminish.

Re: AMD Threadripper 2990WX 32-Core and 2950X 16-Core Review

#143

Post by philwelch » Mon, Aug 13, 2018, 8:27 PM UTC

sandworm101 wrote: post #56

Filligree wrote: post #13

The biggest benefit I've found to running a 1950X isn't something I would have expected, but which perhaps I should have. True, it's much faster than my old system for batch processing, but most of the time it's still idle. Even if it's running Chrome flat-out, as far as the 1950X is concerned, that's idle. Because the two NUMA nodes are ~entirely independent, it's capable of running two independent processes at full…

>> Folklore would have it that single-thread performance is the most important aspect of desktop performance There are a few places where it matters. We talk of "gaming" but that is too broad a term imho. Many AAA games do leverage AMD chips well. They know how to split loads across threads to maximize performance. But in recent years the hot games have come from indi developers. Pre-release titles from tiny develope…

Even when I'm playing Kerbal Space Program, there's a marked difference between just being able to play KSP and being able to play KSP while having reference materials open on another screen (the KSP wiki has a great delta-V map of the Kerbol system, for example). Long before my computer is old enough that games like KSP become unusably slow, it gets old enough that the only way I can run games like KSP is to close my browser and free up all of my resources.

Re: AMD Threadripper 2990WX 32-Core and 2950X 16-Core Review

#144

Post by pantalaimon » Mon, Aug 13, 2018, 8:32 PM UTC

jjuhl wrote: post #78

It seems performance under Linux is significantly better: https://www.phoronix.com/scan.php?page=article&item=amd-linu...

There is also a direct comparison with Windows: https://www.phoronix.com/scan.php?page=article&item=2990wx-l...

Re: AMD Threadripper 2990WX 32-Core and 2950X 16-Core Review

#145

Post by dragontamer » Mon, Aug 13, 2018, 8:32 PM UTC

greglindahl wrote: post #141

dragontamer wrote: post #137

Earlier quoted context omitted.

Intel could do that. But AMD came out with this method first. AMD has only been doing this "infinity fabric" thing for a year. Intel was caught with their pants down. It seems like Intel is researching chiplet technology and trying to recreate AMD's success here. It takes several years to create chips. So Intel realistically won't be able to copy the strategy until 2020 or later. But you better bet that Intel is goin…

AMD introduced HyperTransport in 2001.

HyperTransport and Intel QuickPath isn't chiplet technology.

AMD "upgraded" HyperTransport to Infinity Fabric. Which IIRC uses a bit less power (taking advantage of the shorter, more efficient die-to-die interposer).

Intel has UPI (upgrade over Intel QuickPath), but it hasn't been "shrunk" to chiplet level yet. Intel has EMIB as a physical technology to connect chiplets together... but Intel still needs to create dies and a lower-power protocol for interposer (or maybe EMIB-based) communications.

So Intel has a lot of the technology ready to create a chiplet (like AMD's Zeppelin dies). But Intel wasn't gunning for chiplets as hard as AMD was. Still, Intel demonstrated their chiplet prowess with the Xeon+FPGA over EMIB. So Intel definitely "can" do the chiplet thing, they just are a little bit behind AMD for now.

Re: AMD Threadripper 2990WX 32-Core and 2950X 16-Core Review

#146

Post by shmageggy » Mon, Aug 13, 2018, 8:37 PM UTC

deng wrote: post #69

jdietrich wrote: post #26

Earlier quoted context omitted.

Digital audio workstation workloads are massively multithreaded, with hundreds or thousands of DSP processes. Performance scales almost linearly with core count.

Not my experience. I've had stutters with Ableton Live on a 4 core machine with 2 cores still idling around. Ableton cannot multi-thread a single track (at least in Version 9), and if you're using a single-threaded VST that does not matter anyway.

> Ableton cannot multi-thread a single track (at least in Version 9)

This is still the case in 10, and one of the reasons I have been seriously looking at Bitwig (Linux support being the other).

Re: AMD Threadripper 2990WX 32-Core and 2950X 16-Core Review

#147

Post by mjevans » Mon, Aug 13, 2018, 8:39 PM UTC

blattimwind wrote: post #109

sandworm101 wrote: post #56

Earlier quoted context omitted.

>> Folklore would have it that single-thread performance is the most important aspect of desktop performance There are a few places where it matters. We talk of "gaming" but that is too broad a term imho. Many AAA games do leverage AMD chips well. They know how to split loads across threads to maximize performance. But in recent years the hot games have come from indi developers. Pre-release titles from tiny develope…

Minecraft reigns king in that category. I don't know if it still does, but a couple years ago Minecraft actually managed to somehow still use the OpenGL immediate mode. Back then the larger Minecraft servers required ridiculous amounts of memory and dedicated a dozen cores just to Java's GC.

That's still pretty much the case today. Though the underlying java GL library the desktop client uses has been updated a bit and the newer versions have migrated to higher versions of OpenGL; breaking a lot of mods pretty hard with the changes to the rendering engine.

I hear the (Windows/console only?) version is faster for all the reasons you'd expect, but I'll probably end up never playing it.

Re: AMD Threadripper 2990WX 32-Core and 2950X 16-Core Review

#148

Post by TazeTSchnitzel » Mon, Aug 13, 2018, 8:46 PM UTC

mastax wrote: post #87

blattimwind wrote: post #12

> After core counts, the next battle will be on the interconnect. Low power, scalable, and high performance: process node scaling will mean nothing if the interconnect becomes 90% of the total chip power. I think this means that scaling processors to more cores (nodes) in a lightweight-NUMA scheme just isn't going to work. My guess going forward is that the core counts will stay at the current level for quite a while…

I was amazed at how much power the interconnect was taking on these parts. Even with all the other downsides I was convinced it was the right move, but those power requirements are giving me second (third?) thoughts. The 7nm parts (incl. Ryzen on up) are rumored to use 16-core CCXes, so we should see 64-core EPYC and possibly Threadripper with no worse IC power use. Hopefully they'll make the IC better as well. 7nm E…

The larger the die the worse the yields, and 7nm will have worse yields than previous generations. AMD will go even harder on MCMs because it makes 7nm cost-effective.

Re: AMD Threadripper 2990WX 32-Core and 2950X 16-Core Review

#149

Post by paulmd » Mon, Aug 13, 2018, 8:52 PM UTC

mrkgnao wrote: post #89

Filligree wrote: post #13

The biggest benefit I've found to running a 1950X isn't something I would have expected, but which perhaps I should have. True, it's much faster than my old system for batch processing, but most of the time it's still idle. Even if it's running Chrome flat-out, as far as the 1950X is concerned, that's idle. Because the two NUMA nodes are ~entirely independent, it's capable of running two independent processes at full…

> Because the two NUMA nodes are ~entirely independent, it's capable of running two independent processes at full speed. I don't understand. From my (admittedly little better than layperson's) knowledge, I'm guessing the cores of most multicore processors have to compete for memory access...? Is there a good search term I can use to help me understand what's going on here?

Threadripper and Epyc are essentially multi-socket-in-a-package. There is an inter-processor link which is analogous to Intel QPI or DMI, it just runs between dies within a single socket instead of dies in separate sockets.

Threadripper and Epyc present themselves as 2 or 4 separate NUMA nodes depending on model. Spreading a single task across multiple NUMA nodes usually hurts performance significantly (often slower than just running it on a single node using fewer threads), but you can run 2/4 separate tasks at pretty much full speed.

The new WX processors are a little weird because two of the NUMA nodes have no direct access to RAM at all, they have to ask the other 2 dies to do it for them and pass it over.

Re: AMD Threadripper 2990WX 32-Core and 2950X 16-Core Review

#150

Post by paulmd » Mon, Aug 13, 2018, 8:54 PM UTC

philwelch wrote: post #142

Filligree wrote: post #13

The biggest benefit I've found to running a 1950X isn't something I would have expected, but which perhaps I should have. True, it's much faster than my old system for batch processing, but most of the time it's still idle. Even if it's running Chrome flat-out, as far as the 1950X is concerned, that's idle. Because the two NUMA nodes are ~entirely independent, it's capable of running two independent processes at full…

One instance of this might be "running a performance-intensive game fullscreen on one virtual desktop while having a browser open to read strategy guides on another virtual desktop". This is a common use case for me that also seems to be the first place where performance starts to diminish.

Having a browser open uses approximately 0% CPU though.

Streaming would be a better example.