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Intel’s High-End Cascade Lake CPUs to Support 3.84 TB of Memory per Socket

anandtech.com

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Re: Intel’s High-End Cascade Lake CPUs to Support 3.84 TB of Memory per Socket

#61

Post by xxs »

rbanffy wrote: post #56
gameswithgo wrote: post #44

Earlier quoted context omitted.

as core count goes up the number of tasks that can be sped up starts to shrink, because memory access and throughput become more and more of a limiter. That is why you tend to see huge l3 caches on the big core cpus, it helps but it can still be a challenge to load up all 32 cores and get any speedup, for many workloads. l3 cache is not THAT much faster than ram. that is why I tend to eye the ~6 core machines for des…

If we can balance the L1 cache eviction rate for the extra cores (since L1 is not shared), memory bandwidth pressure will be lower. These monsters also have a lot of memory channels to address memory hunger. I still think we can push the envelope a bit further for most common desktop software.

L1 cannot be too big and it should not grow any larger. L2 is a better option being 'only' 3 times slower than L1 (L1 tend to be ~3 clocks to read). L3 is an interesting concept. Communication through L3 is quite beneficial in concurrent programming when done right; other than that it's there to hide the latency of accessing RAM. However, it's shared and easy to trash.

The software developers could do a lot for memory throughput hungry applications (datastructure layout, not using bloated strings for everything, not using linked lists, etc.), alas memory based optimizations almost never happen and tend to require a great deal of hardware understanding + non scripting language(s).

Re: Intel’s High-End Cascade Lake CPUs to Support 3.84 TB of Memory per Socket

#62

Post by twtw »

imglorp wrote: post #50
jstewartmobile wrote: post #27

Cores! Gigahertz! Terabytes! Odds are... still f-ing busted. How will the numbers look after the next Spectre/TLBleed/etc patch? I'd be more impressed by a boring processor that works.

Good question. It's probably WAY too soon to expect any hardware that's not full of vulnerabilities in the pipeline, TPM, and microcode. They need to redesign their cores from the ground up. When will that happen?

Never. Not going to happen.

Re: Intel’s High-End Cascade Lake CPUs to Support 3.84 TB of Memory per Socket

#63

Post by ben-schaaf »

qoi2ijds0 wrote: post #22
djsumdog wrote: post #15

Earlier quoted context omitted.

I got a Ryzen 7 for my recent build and am pretty happy with it.

Same, bought a 2700x and couldn't be happier... the extra cores does wonders for using something like intellij whilst browsing / gaming. You only need something like an 8700k / 8086k if you have a 100hz+ monitor and want to spend more money than necessary on a dead socket. AMD are really landing the uppercuts this time round

I've got a R5 1600X with overclocked RAM (3GHz) and a 144Hz display. I've yet to encounter a game that doesn't bottleneck on the GPU with vsync on. Either it hits beyond 144fps and it wouldn't matter, or its below 144fps bottlenecked on the GPU.

Re: Intel’s High-End Cascade Lake CPUs to Support 3.84 TB of Memory per Socket

#64

Post by eloff »

nordsieck wrote: post #3
dantiberian wrote: post #2

A few months ago Intel pulled a stunt where they showed a 28 core 5GHz CPU, implying it was a production CPU that would ship this year. They failed to mention that it was attached to an industrial compressor to supply the necessary cooling for the overclocked CPU, and that it was a server socket ( https://www.anandtech.com/show/12932/intel-confirms-some-det... ). Since then, whenever I see a headline with Intel in it…

Case in point: > chips will support up to 3.84 TB of memory per socket ... due to combining 512 GB Optane DIMMs and 128GB DDR4 DIMMs > ... > in a 6 x Optane and 6 x DDR4 configuration, they will provide 3072 GB of 3D XPoint memory and 768 GB of DDR4 RAM for a total of 3.84 TB of memory Optane DIMMs don't really have the performance characteristics of traditional DRAM. It sounds like the real capacity per socket is 12…

Well at least it can address 3.84 TB of RAM (maybe more, because that's not a multiple of a power of two.) I suppose if you could get 256GB DDR4 DIMMs you'd have 12*256 = 3072 = 3TB of RAM. Yuu'd have to give the RAM cartel your first-born to pay for it, but that would be some machine!

Re: Intel’s High-End Cascade Lake CPUs to Support 3.84 TB of Memory per Socket

#65

Post by ben-schaaf »

sandworm101 wrote: post #47
aoeusnth1 wrote: post #37

Earlier quoted context omitted.

Why does threadripper need to be competitive in the server space? Edit: emphasis on threadripper , which is a consumer product.

The server market is like Formula One for chip makers. It is where there is enough money to really push the limits of the technology. Competing in such leagues brings institutional knowledge, and bragging rights. Servers is also where you get back-and-forth discussions with customers large enough to be worth listening to. Getting useful feedback from the users of desktop CPUs is difficult and time-consuming. But some…

Threadripper doesn't target servers, their EPYC line does...

Re: Intel’s High-End Cascade Lake CPUs to Support 3.84 TB of Memory per Socket

#66

Post by snef »

quantumwoke wrote: post #10

I've weighed up the pros and cons, and my next processor will be the 32 core AMD cpu. This seems much better value than anything Intel has to offer.

Much agreed. I've wanted a high core count cpu for absolutely no reason for the longest time. I can't wait to spend thousands of dollars on a cpu just to improve compile times by a few seconds. -j64 anyone?

Re: Intel’s High-End Cascade Lake CPUs to Support 3.84 TB of Memory per Socket

#67

Post by sixothree »

spacentropy wrote: post #58
ksec wrote: post #43

What I really wanted to know is the performance difference in Postgre / MySQL, between 128GB of DRAM, with 1TB of SSD, 1TB of Optane via PCI-E, and Optane DIMM.

Here's some benchmark for MySQL, SSD vs Optane (Intel vs Intel): http://dimitrik.free.fr/blog/posts/mysql-performance-80-ga-i...

Not optane dimm though?

Re: Intel’s High-End Cascade Lake CPUs to Support 3.84 TB of Memory per Socket

#68

Post by theevilsharpie »

aoeusnth1 wrote: post #37
theevilsharpie wrote: post #25

Earlier quoted context omitted.

Threadripper may come close in core count, but it cannot use registered memory, which means it's limited to 128 GB of RAM (based on the current maximum UDIMM capacities). That's not competitive in the server space.

Why does threadripper need to be competitive in the server space? Edit: emphasis on threadripper , which is a consumer product.

> Why does threadripper need to be competitive in the server space?

It doesn't, and AMD doesn't market Threadripper for server use. It only came up in this discussion because of a misunderstanding of Threadripper's capabilities.

Re: Intel’s High-End Cascade Lake CPUs to Support 3.84 TB of Memory per Socket

#69

Post by ChuckMcM »

dantiberian wrote: post #2

A few months ago Intel pulled a stunt where they showed a 28 core 5GHz CPU, implying it was a production CPU that would ship this year. They failed to mention that it was attached to an industrial compressor to supply the necessary cooling for the overclocked CPU, and that it was a server socket ( https://www.anandtech.com/show/12932/intel-confirms-some-det... ). Since then, whenever I see a headline with Intel in it…

Well they do feel a bit under siege according to the press so one might expect them to put their best foot forward. Not that I think they should pull shenanigans like that but it is common for companies, especially tech companies, to do this when they perceive they are losing ground to a competitor.

As others have pointed out, the addition comes from their support of Optane "dimms" which have much higher densities than DDR4 memory in the same form factor.

This is going to give the folks who write schedulers some more variants to play with. First it was per core memory, then it was per socket memory per core, and now it is memory type per socket per core. So you don't want your process running on Core3 with its pages mapped to Optane memory that is attached to the other socket (worst case).

Re: Intel’s High-End Cascade Lake CPUs to Support 3.84 TB of Memory per Socket

#70

Post by ChuckMcM »

throwaway2048 wrote: post #6
nordsieck wrote: post #3

Earlier quoted context omitted.

Case in point: > chips will support up to 3.84 TB of memory per socket ... due to combining 512 GB Optane DIMMs and 128GB DDR4 DIMMs > ... > in a 6 x Optane and 6 x DDR4 configuration, they will provide 3072 GB of 3D XPoint memory and 768 GB of DDR4 RAM for a total of 3.84 TB of memory Optane DIMMs don't really have the performance characteristics of traditional DRAM. It sounds like the real capacity per socket is 12…

Intel keep positioning optane as "close to dram" preformance (especially with misleading marketing nonsense like this), it does have some advantages over flash, mostly related to random access times, but its nowhere near the orders of magnitude more preformant that something would require to fill the preformance point between DRAM and SSDs. Optane is almost entirely hype, with no substance.

You and mtgx both mention Optane performance is "not even close to dram." I'm interested in if you have found anyone who has benchmarked the DIMM version with respect to actual DRAM. I see several sites that have benchmarked the Nvme version but this has additional hoops that the DIMM version would not have to jump through and so I've been on the lookout from Anandtech or another reputable source for actual numbers.
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