Assessing IBM's POWER8, Part 2: Server Applications on OpenPOWERby Johan De Gelas on September 15, 2016 8:01 AM EST
A large part of the server market is very sensitive to performance-per-watt. That includes the cloud vendors/hosts. For a smaller part of the market, top performance is more important than the performance/watt ratio. Indeed, for financial trading, big data analyses, large databases, and most HPC servers, total performance is the top priority. Energy consumption should not be outrageous, but it is not the most important concern.
We tested the energy consumption of our servers for a one-minute period in several situations. The first one is the point where the tested server performs best in MySQL: the highest throughput just before the response time goes up significantly. Then we look at the point where throughput is the highest (no matter what response time). This is the situation where the CPU is fully loaded.
at Lowest Resp. Time
|IBM POWER8 S812LC||190 W||221||259||260||14482||55|
|Xeon E5-2699 v4||145 W||67||213||235||18997||89|
|Xeon E5-2690 v3||135 W||84||249||254||11741||47|
Throughput and single threaded performance were the priorities for designing POWER8. Power consumption stood probably much lower on the list, way behind RAS. The idle power shows us that you should not use the POWER8 in applications that run at low load for long periods.
Intel's "Broadwell-EP" (Xeon E5 v4), by comparison, is the clear victor when it comes to performance per watt, and even without looking at Intel's background, it's clear from the data alone that more thought was put into that aspect.
However, considering that the POWER8 was launched around the same time as Intel Haswell, IBM's multicore delivers a lot of integer performance per watt of energy it consumes. In fact, despite the power gobbling Centaur chips, despite the fact that MySQL is not the most POWER8 optimized application, IBM's medium range POWER8 is capable of defeating Intel's Haswell. While this is less relevant to the server buyer today, it does show that IBM's engineering capabilities are competitive with Intel, which is good news for the upcoming POWER9 chip. The POWER9 chip will be the first POWER chip which has specific SKUs for the affordable scale out servers.