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AMD Ryzen Threadripper 3000 32-core CPU is more bad news for Intel

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Re: AMD Ryzen Threadripper 3000 32-core CPU is more bad news for Intel

#151

Post by BubRoss »

eyegor wrote: post #111
JohnJamesRambo wrote: post #101

Earlier quoted context omitted.

What are the physics problems?

Fluid flow and most particle simulations with a large number of particles. The limiting factor is the inter particle interactions, so all the calculations have to feed back into each other.

Both of those problems are well worn and can scale to as many cores as we can put in a single computer.

Whether it is a navier-stokes grid/image fluid simulation, arbitrary points in space that work off of nearest neighbors or a combination of both (by rasterizing into a grid and using that to move the particles), there are many straightforward ways to use lots of CPUs.

Fork join parallelism is a start. Sorting particles into a kd-tree is done by recursively partitioning and the partitions can be distributed amount cores. The sorting structure can be read but not written by as many cores as you want, and thus their neighbors can be searched and found by all cores at once.

Re: AMD Ryzen Threadripper 3000 32-core CPU is more bad news for Intel

#152

Post by txdv »

loeg wrote: post #71

By what mechanism would the multicore performance rise 2x without increased single-core performance? I'm kind of confused. Eliminating intra-CPU concurrency bottlenecks, I guess?

All the cores need to synchronize memory between each other, I guess you can improve speed on that part.

Re: AMD Ryzen Threadripper 3000 32-core CPU is more bad news for Intel

#153

Post by 0-_-0 »

celrod wrote: post #128
luizfelberti wrote: post #118

Earlier quoted context omitted.

Is AVX512 really an advantage though? Intel is infamous for severely downclocking the processor for these and other AVX/SSE family instructions, to a point where sometimes using them makes the program slower than it would be otherwise, especially if you're constantly provoking frequency switches between them and regular instructions. AMD might not have implemented AVX512 specifically yet (there's nothing legally keep…

You can look at binning statistics for non-avx/avx2/avx512 clock speeds: https://siliconlottery.com/pages/statistics For example, the worst 7980XEs do 4.1/3.8/3.6 GHz for each of these respectively. 0.5 GHz down clock isn't too bad. You can change these settings in your bios however you'd like on the unlocked CPUs (ie, the HEDT lineup + W3175X). I do find those down clocks are necessary; I've passed 100C with a 360mm…

> I've passed 100C with a 360mm radiator and roaring fans

Damn, which radiator? Was there a GPU under load in your water loop?

Re: AMD Ryzen Threadripper 3000 32-core CPU is more bad news for Intel

#154

Post by loeg »

paulmd wrote: post #141
loeg wrote: post #122

Earlier quoted context omitted.

Wouldn't the higher clocks impact single-core performance? The article claims that's about the same. I suppose the userbenchmark single-core perf test[1] (the article links to some userbenchmark.com results) could just be a bad test; I'm unfamiliar with it. (It could also be that 2990WX wasn't power/heat limited on a single core, and neither is 3xxx; but say, at 16 core 100% clock, 3xxx can go higher than 2990WX due…

Zen2 is moving to a somewhat deceptive advertising model for clocks. AMD is advertising the absolute highest that any core on the die can hit under extremely light load for an absolute instant. Sustained single-core clocks will be 100-200 MHz less and sustained all-core will be significantly less. Most cores on a chip are not capable of sustaining the advertised clockrate even under severe voltage and even for instan…

I don't actually recall any Zen2 clock advertising in particular. My comment was purely in response to your earlier statement:

> Another part is the power consumption and resulting higher clocks. The 2990WX was basically power limited, the new chips are on 7nm which will drastically reduce their power consumption and allow higher clocks inside the same power envelope.

Re: AMD Ryzen Threadripper 3000 32-core CPU is more bad news for Intel

#155

Post by dlemire »

dragontamer wrote: post #142
d33 wrote: post #91

Earlier quoted context omitted.

Interesting! Is there a simple way to measure memory latency?

Create 1-billion 32-bit integers numbers between 0 to 1-billion. Knuth shuffle the integers. "Linked list" traverse the integers as follows: //array is full of 1-billion numbers, randomly sorted uint32_t idx = 0; for(int i=0; i Pull out a stopwatch (or use Linux's "time" functionality). Divide the time by 200000000. You've now measured memory latency.

I suggest using Sattolo’ algorithm instead.

Here is a relevant blog post https://lemire.me/blog/2018/11/13/memory-level-parallelism-i...

Re: AMD Ryzen Threadripper 3000 32-core CPU is more bad news for Intel

#156

Post by tuananh »

khalilravanna wrote: post #68

But will they actually be generally available for purchase? I was super excited to grab an AMD Ryzen 3900x when they came out mid-July and they've been consistently sold out since then. That's over 3 months with the only reliable way to get one being to buy one for almost twice the MSRP from 3rd party resellers at $800-900 vs MSRP of $500.

demand in US is really high. in my country (SEA), 3900x is available almost every big computer shop.

Re: AMD Ryzen Threadripper 3000 32-core CPU is more bad news for Intel

#157

Post by NullPrefix »

capableweb wrote: post #99
mrguyorama wrote: post #45

Earlier quoted context omitted.

Honestly with the way chrome and firefox behave nowadays, even grandma looking at facebook benefits from multiple cores

Not really, any window/tab that is not in focus gets heavily throttled by the browser, gradma is probably not running any extensions and single websites are still single threaded for most parts (more and more are adding web workers for various parts though)

>not running any extensions and single websites are still single threaded for most parts

Such a shame that all that JS botnet is still single threaded, isn't it ?

Re: AMD Ryzen Threadripper 3000 32-core CPU is more bad news for Intel

#158

Post by tracker1 »

twotwotwo wrote: post #44

Worth noting AMD just announced that the first third-gen Threadripper will come out in Nov with 24 cores, and the planned 16-core mainstream chip (the 3950X) is delayed to November: https://www.tomshardware.com/news/amd-ryzen-9-3950x-delay-la... A 32-core chip is still almost certain to show up, since benchmarks have leaked, and folks have also leaked some pics of 3950X's and packaging, but I guess supply/demand have…

TSMC has also had issues meeting demand directy, they're at a 6 month backlog for 7nm. It seems like the demand has been huge, and a lot of server vendors who have been waiting to upgrade servers are going AMD and pulling the triggers now.

The 3900X has been pretty much sold out since launch, and sells out within hours of inventory showing on newegg/amazon. Been using a 3600 on a new build, waiting for 3950X. And likewise a lot of the aftermarket design rx5700xt cards have been selling out quickly. Took 4 tries to get the gigabyte one. First two times, sold out before I saw the notice, third it sold out while in my card going through checkout. Then I got the order in.

Re: AMD Ryzen Threadripper 3000 32-core CPU is more bad news for Intel

#159

Post by astrodust »

rbanffy wrote: post #32
astrodust wrote: post #17

Earlier quoted context omitted.

If you ever get into Docker/Kubernetes, being able to spin up a local cluster for testing is a pretty big deal. Having that running in the background and not impacting your usual workload is huge. I've been testing a Kubernetes cluster built on 32-core AMD servers and it's unreal the workloads you can throw at them. I'm used to 4 or 8-core Xeon chips and this is a whole different game.

That's true, but memory/IO is a much bigger issue in this scenario than processing power. While running a cluster in VMs, I'm frequently limited by IO (and if your VMs use more memory than it's physically available, you'll quickly descent into swap hell) well before my CPUs register a significant uptick in usage. And, mind you, my workstation is 4 year old Xeon with 64 gigs of memory and reasonably fast (but not amaz…

Consider: NVMe makes SSD look like HDD.

More PCIe channels means more NVMe as most servers don't use those channels for GPU.

Re: AMD Ryzen Threadripper 3000 32-core CPU is more bad news for Intel

#160

Post by astrodust »

marmaduke wrote: post #30
astrodust wrote: post #17

Earlier quoted context omitted.

If you ever get into Docker/Kubernetes, being able to spin up a local cluster for testing is a pretty big deal. Having that running in the background and not impacting your usual workload is huge. I've been testing a Kubernetes cluster built on 32-core AMD servers and it's unreal the workloads you can throw at them. I'm used to 4 or 8-core Xeon chips and this is a whole different game.

How much of that is core count though? I've used minikube several times and it didn't seem to matter much how many cores it had (beyond 4)

For simple things it doesn't matter, but if you're bringing up a complex application that has a dozen server components and putting it under load, it does matter.
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