Assessing Cavium's ThunderX2: The Arm Server Dream Realized At Last
by Johan De Gelas on May 23, 2018 9:00 AM EST- Posted in
- CPUs
- Arm
- Enterprise
- SoCs
- Enterprise CPUs
- ARMv8
- Cavium
- ThunderX
- ThunderX2
SPEC CPU2006 Cont: Per-Core Performance w/SMT
Moving beyond single-threaded performance, multi-threaded performance within the confines of a single core is of course also important. The Vulcan CPU architecture was designed from the start to leverage SMT4 to keep its cores occupied and boost their overall throughput, so this is where we'll look next.
SPEC CPU2006: Single Core w/SMT | ||||||
Subtest SPEC CPU2006 Integer |
Application Type | Cavium ThunderX 2 GHz gcc 5.2 1 thread |
Cavium ThunderX2 @2.5 GHz gcc 7.2 4 threads |
Xeon 8176 @3.8 GHz gcc 7.2 2 threads |
Thunder X2 vs Xeon 8176 |
Thunder X2 vs ThunderX |
400.perlbench | Spam filter | 8.3 | 24.1 | 50.6 | 48% | 290% |
401.bzip2 | Compression | 6.5 | 22.9 | 31.9 | 72% | 350% |
403.gcc | Compiling | 10.8 | 35 | 38.1 | 92% | 330% |
429.mcf | Vehicle scheduling | 10.2 | 52.4 | 50.6 | 104% | 510% |
445.gobmk | Game AI | 9.2 | 25.1 | 35.6 | 71% | 270% |
456.hmmer | Protein seq. analyses | 4.8 | 26.7 | 41 | 65% | 560% |
458.sjeng | Chess | 8.8 | 22.4 | 37.1 | 60% | 250% |
462.libquantum | Quantum sim | 5.8 | 83.6 | 83.2 | 100% | 1440% |
464.h264ref | Video encoding | 11.9 | 34 | 66.8 | 51% | 290% |
471.omnetpp | Network sim | 7.3 | 31.1 | 41.1 | 76% | 440% |
473.astar | Pathfinding | 7.9 | 27.2 | 33.8 | 80% | 340% |
483.xalancbmk | XML processing | 8.4 | 33.8 | 75.3 | 45% | 400% |
First of all, the ThunderX2 core is a massive improvement over the simple ThunderX core. Even excluding libquantum – that benchmark could easily run 3 times faster on the older ThunderX core after some optimization and compiler improvements – the new ThunderX2 is no less than 3.7 times faster than its older brother. This kind of an IPC advantage makes the original ThunderX's 50% core advantage all but irrelevant.
Looking at the impact of SMT, on average, we see that 4-way SMT improves the ThunderX2's performance by 32%. This ranges from 8% for video encoding to 74% for pathfinding. Intel meanwhile gets a 18% boost from their 2-way SMT, ranging from 4% to 37% in the same respective scenarios.
Overall, a boost of 32% for the ThunderX2 is decent. But it does invite an obvious comparison: how does it fare relative to another SMT4 architecture? Looking at IBM's POWER8, which also supports SMT4, at first glance there seems to be some room for improvement, as the POWER8 sees a 76% boost in the same scenario.
However this isn't entirely an apples-to-apples comparison, as the IBM chip had a much wider back-end: it could issue 10 instructions while the ThunderX2 core is limited to 6 instructions per cycle. The POWER8 core was also much more power hungry: it could fit only 10 of those ultra-wide cores inside a 190W power budget on a 22 nm process. In other words, further increasing the performance gains from using SMT4 would likely require even wider cores, and in turn seriously impact the total number of cores available inside the ThunderX2. Still, it is interesting to put that 32% number into perspective.
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Wilco1 - Wednesday, May 23, 2018 - link
That's your uninformed opinion... Microsoft has different plans.ZolaIII - Thursday, May 24, 2018 - link
Windows is DOA anyway. M$ makes more money this day's on Linux then it does on Window's combined. Only thing making it still alive is MS Office but even that will change in couple of years.Wilco1 - Thursday, May 24, 2018 - link
Calling Windows dead when it ships on 95+% of PCs sold is eh... a little bit premature. Get back to me when 50+% of PCs ship with Linux instead of Windows.ZolaIII - Friday, May 25, 2018 - link
Get back to me when windows ships with 5% in; servers, embedded, router's, smartphones...jimbo2779 - Thursday, May 24, 2018 - link
In what way is it making more from Linux?ZolaIII - Friday, May 25, 2018 - link
https://www.computerworld.com/article/3271085/micr...Even your Windows PC, Office and everything else from Microsoft this day's is backed up by a cloud which is Linux based.
defaultluser - Wednesday, May 23, 2018 - link
Page 11 has "Apache Spark and Energy Consumption" in the title, but the page only containsApache Spark results. WHERE IS THE ENERGY CONSUMPTION?
We need power consumption tests during benchmarks to show if the architecture has better perf/watt than Intel. Otherwise, why did you publish this obviously incomplete article?
Ryan Smith - Wednesday, May 23, 2018 - link
Whoops. Sorry, that was a small section that was moved to page 5.ruthan - Wednesday, May 23, 2018 - link
Well, where is the most important chart performance per dollar comparison with x86 solution?That virtualization support, is some arm specific yes i we need feature and proprietary hell like Lpars.. or its finally support Vmware? - that means virtualization.
Where is could it run Crysis test?
HStewart - Wednesday, May 23, 2018 - link
VMWare is not currently support - and probably not for a long time - unless they ran in emulation mode and it would slower than Atomhttps://kb.vmware.com/s/article/1003882