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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Panxa - Sunday, July 16, 2017 - link
"Competition has spoiled the naming convention Intels 14 === competetions 7 or 10"The node naming convention used to be the gate length, however that has become irrelevant. Intel 14 nm gate lenghth is about 1.5x and 10 nm about 1.8x. Companies and organizations have developed quite accurate models to asses process density with equations based on process poarameters like CPP and MPP to what they call a "standard node"
"Intel used to maintain 2 year lead now grew that to 3-4year lead"
Don't belive intel propaganda. Intel takes the lead in 2014 with their 14nm process with a standard node value of 12.1. Samsung and then TSMC take the lead in 2017 with their 10nm processes having standard node values of 11.2 and 10.3 respectively. Intel will retake the the lead back when they deliver their 10nm process with a standard node value of 8.3. However it will be a short lived lead, TSMC will retake the lead back with their 7nm with a standard node of 7.9 before GLOBALFOUNDRIES takes the lead in 2018 with their 7nm process with a standard node value of 7.8. The gap is gone !!!
"yet their revenue profits grow year over year"
Wrong. Intel revenue for the last years remained fairly constant
2011 grow
2012 decline
2013 decline
2014 grow
2015 decline
2016 grow
All in all from 2011 to 2016 revenue went from 54 billion to 59 billion. If we take into account inflation $54 billion in the year 2011 is worth $58.70 billion today.
Not to mention that Samsung has overtaken Intel to become the world No.1 semiconductor company, and that a "pure play" foundry like TSMC has surpassed intel in market CAP
johnp_ - Wednesday, July 12, 2017 - link
The Xeon Bronze Table on Page 7 seems to have an error. It lists the 4112 as having 5.50MB L3, but ark says it has 8.25MB, just like the 3104, so it looks like it has an above-average L3/Core:https://ark.intel.com/products/123551
Ian Cutress - Friday, July 14, 2017 - link
I've got Intel documents from our briefings that say it has the regular 1.375MB/core allocation, and others saying it has 8.25MB. I'm double checking.johnp_ - Friday, July 21, 2017 - link
All commercial listings and most reviews I've seen online show the processor with 8.25MB as well.Do you have any further information from Intel?
pepoluan - Wednesday, July 12, 2017 - link
What I'm dying to know: Performance when running as virtualization host. Using Xen, VMware, and Hyper-V.Threska - Saturday, July 22, 2017 - link
Virtualization itself, and more importantly virtualization security.Sparkyman215 - Wednesday, July 12, 2017 - link
Typo here: Intel will seven different versions of the chipset, varying in 10G and QAT support, but also varying in TDP:tmbm50 - Wednesday, July 12, 2017 - link
One thing to consider when considering value is the Microsoft Server 2016 core tax.....assuming your mission critical apps are still tied to MS ;-)Server 2016 now chargers per core with an 8 core socket as the base. The Window license for a 32 core server is NUTS.
I'm surprised AMD and Intel are not pushing Microsoft on this. For datacenters like ourselves its pushing us to 8 core sku's with more 2U nodes.
msroadkill612 - Wednesday, July 12, 2017 - link
Aye, its a fuuny world lad.The way the automobile panned out differently in different countries, was laargely die to fuel tax regimes, rather than technology.
i.e. what is the best way to cheat a bit on the incumbent tax rules of germany/france/uk vs a more laissez faire USA. In UK, u were taxed on horsepower, but u could cheat a bit w/ hi revs & more gears - that sort of thing.
rahvin - Wednesday, July 12, 2017 - link
Who runs any Windows service on bare metal these days? If you haven't virtulalized your windows servers running on KVM you should.