Sizing Up Servers: Intel's Skylake-SP Xeon versus AMD's EPYC 7000 - The Server CPU Battle of the Decade?
by Johan De Gelas & Ian Cutress on July 11, 2017 12:15 PM EST- Posted in
- CPUs
- AMD
- Intel
- Xeon
- Enterprise
- Skylake
- Zen
- Naples
- Skylake-SP
- EPYC
Intel's Optimized Turbo Profiles
Also new to Skylake-SP, Intel has also further enhanced turbo boosting.
There are also some security and virtualization enhancements (MBE, PPK, MPX) , but these are beyond the scope this article as we don't test them.
Summing It All Up: How Skylake-SP and Zen Compare
The table below shows you the differences in a nutshell.
AMD EPYC 7000 |
Intel Skylake-SP | Intel Broadwell-EP |
|
Package & Dies | Four dies in one MCM | Monolithic | Monolithic |
Die size | 4x 195 mm² | 677 mm² | 456 mm² |
On-Chip Topology | Infinity Fabric (1-Hop Max) |
Mesh | Dual Ring |
Socket configuration | 1-2S | 1-8S ("Platinum") | 1-2S |
Interconnect (Max.) Bandwidth (*)(Max.) |
4x16 (64) PCIe lanes 4x 37.9 GB/s |
3x UPI 20 lanes 3x 41.6 GB/s |
2x QPI 20 lanes 2x 38.4 GB/s |
TDP | 120-180W | 70-205W | 55-145W |
8-32 | 4-28 | 4-22 | |
LLC (max.) | 64MB (8x8 MB) | 38.5 MB | 55 MB |
Max. Memory | 2 TB | 1.5 TB | 1.5 TB |
Memory subsystem Fastest sup. DRAM |
8 channels DDR4-2666 |
6 channels DDR4-2666 |
4 channels DDR4-2400 |
PCIe Per CPU in a 2P |
64 PCIe (available) | 48 PCIe 3.0 | 40 PCIe 3.0 |
(*) total bandwidth (bidirectional)
At a high level, I would argue that Intel has the most advanced multi-core topology, as they're capable of integrating up to 28 cores in a mesh. The mesh topology will allow Intel to add more cores in future generations while scaling consistently in most applications. The last level cache has a decent latency and can accommodate applications with a massive memory footprint. The latency difference between accessing a local L3-cache chunk and one further away is negligible on average, allowing the L3-cache to be a central storage for fast data synchronization between the L2-caches. However, the highest performing Xeons are huge, and thus expensive to manufacture.
AMD's MCM approach is much cheaper to manufacture. Peak memory bandwidth and capacity is quite a bit higher with 4 dies and 2 memory channels per die. However, there is no central last level cache that can perform low latency data coordination between the L2-caches of the different cores (except inside one CCX). The eight 8 MB L3-caches acts like - relatively low latency - spill over caches for the 32 L2-caches on one chip.
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deltaFx2 - Thursday, July 13, 2017 - link
"Can you mention one innovation from AMD that changed the world?" : None. But the same applies to Intel too, save, I suppose, the founders (Moore and Noyce) contributions to IC design back when they were at Fairchild/Shockley. That's not Intel's contribution. Computer Architecture/HPC? That's IBM. They invented the field along with others like CDC. Intel is an innovator in process technology, specifically manufacturing. Or used to be... others are catching up. That 3-yr lead that INtel loves to talk about is all but gone. So with that out of the way...AMD's contributions to x86 technology: x86-64, hypertransport, integrated memory controller, multicore, just to name a few. Intel copied all of them after being absolutely hammered by Opteron. Nehalem system architecture was a copy-paste of Opteron. It is to AMD's discredit that they ceded so much ground on the CPU microarchitecture since then with badly executed Bulldozer, but it was AMD that brought high-performance features to x86 server. Intel would've just loved to keep x86 on client and Itanium on server (remember that innovative atrocity?). Then there's a bunch on the GPU side (which INtel can't get right for love or money), but that came from an acquisition, so I won't count those.
"AMD exists because they are always inferior". Remember K8? It absolutely hammered intel until 2007. Remember Intel's shenanigans bribing the likes of Dell to not carry K8? Getting fined in the EU for antitrust behaviors and settling with AMD in 2010? Not much of a memory card on you, is there?
AMD gaining even 5-10% means two things for intel: Lower margins on all but the top end (Platinum) and a loss in market share. That's plain bad for the stock.
"Intel is a data center giant have head start have the resources...". Yes, they are giants in datacenter compute. 99% market share. Only way to go from there is down. Also, those acquisitions you're talking about? Only altera applies to the datacenter. Also, remember McAfee for an eye-watering $7.8 bn? How's that working out for them?
Shankar1962 - Wednesday, July 12, 2017 - link
Nvidia who have been ahead than Intel in AI should be the more competent threatHow much market share Intel loses depends on how they compete against Nvidia
Amd will probably gain 5% by selling products for cheap prices
Intel controls 98/99% share so it's inevitable to lose a few % as more players see the money potential but unless Intel loses to Nvidia there is annuphill battle for Qualcomm ARM.
HanSolo71 - Wednesday, July 12, 2017 - link
Could you guys create a Benchmark for Virtual Desktop Solutions? These AMD chips sound awesome for something like my Horizon View environment where I have hundreds of 2 core 4GB machines.Threska - Saturday, July 22, 2017 - link
For VDI wouldn't either an APU setup, or CPU+GPU be better?msroadkill612 - Wednesday, July 12, 2017 - link
Kudos to the authors. I imagine its gratifying to have stirred such healthy & voluminous debate :)milkod2001 - Thursday, July 13, 2017 - link
Are you guys still updating BENCH results? I cannot find there benchmark results for RYZEN CPUs when i want to compare them to others.Ian Cutress - Friday, July 14, 2017 - link
They've been there since the launchAMD (Zen) Ryzen 7 1800X:
http://www.anandtech.com/bench/product/1853
KKolev - Thursday, July 13, 2017 - link
I wonder if AMD'd EPYC CPU's can be overclocked. If so, the AMD EPYC 7351P would be very interesting indeed.uklio - Thursday, July 13, 2017 - link
How could you not do Cinebench results?! we need an answer!JohanAnandtech - Thursday, July 13, 2017 - link
I only do server benchmarks, Ian does workstation. Ian helped with the introduction, he will later conduct the workstation benchmarks.