Bulldozer for Servers: Testing AMD's "Interlagos" Opteron 6200 Series
by Johan De Gelas on November 15, 2011 5:09 PM ESTTrueCrypt 7.1 Benchmark
TrueCrypt is a software application used for on-the-fly encryption (OTFE). It is free, open source and offers full AES-NI support. The application also features a built-in encryption benchmark that we can use to measure CPU performance. First we test with the AES algorithm (256-bit key, symmetric).
You can compare those numbers directly with Anand's benchmark here. The Core i7-2600K at 3.4GHz delivers 3.4GB/s and the AMD FX-8150 at 3.6GHz about the same 3.3GB/s. We get about 2.3 times the performance here with four times as many "cores", but at 2.3GHz instead of 3.6GHz.
We also test with the heaviest combination of the cascaded algorithms available: Serpent-Twofish-AES.
The combination benchmark is limited by the slowest algorithms: twofish and serpent. The huge advantage that the architectures (Opteron "Bulldozer" and Xeon "Westmere") which support AES-NI had has evaporated: the Opteron 6174 keeps up with the best Xeons. The Opteron 6276 can leverage its higher threadcount as this benchmark scales extremely well.
It is good to realize that these benchmarks are not real-world but rather synthetic. It would be better to test a website that does some encrypting in the background or a fileserver with encrypted partitions. In that case the encryption software is only a small part of the total code being run. A large performance (dis)advantage might translate into a much smaller performance (dis)advantage in that real-world situation.
For example, eight times faster encryption resulted in a website with 23% higher throughput and a 40% faster encrypted file (see here). The advantage that the Xeon had in the first benchmark will not be noticeable, and the Opteron's 24% higher performance will translate into a few percentage points. But this is a benchmark where AMD's efforts to get a 16 integer cores inside a 115W TDP pay off.
7-Zip 9.2
7-zip is a file archiver with a high compression ratio. 7-Zip is open source software, and most of the source code is under the GNU LGPL license
Compression is more CPU intensive than decompression, and the latter depends a little more on memory bandwidth. When it comes to load/stores and memory bandwidth, the Opteron 6276 is unbeateable. We've also seen indications that Bulldozer's cache does very well in reads but not so well in writes, and that could account for some of the gap between the compress/decompress results.
Compression is for a part determined by the quality of the branch predictor (higher than normal branch mispredictions on mediocre branch predictors). The Opteron 6276 has a better branch predictor than the Opteron 6174, but the branch misprediction penalty has grown from 12 to 20 cycles. As a result, a single branch intensive thread runs slower (see Anand's tests) on the newest AMD architecture. Luckily, the AMD Opteron 6276 can compensate for this with its 16 threads (vs 12 threads for the Opteron 6172) and a little bit of help from Turbo Core.
Intel still has the best branch predictors in the industry. The result is that the Xeon is by far the fastest compressor. The end result is that the Xeon is the more rounded CPU in this discipline.
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Kevin G - Tuesday, November 15, 2011 - link
I'm curious if CPU-Z polls the hardware for this information or if it queries a database to fetch this information. If it is getting the core and thread count from hardware, it maybe configurable. So while the chip itself does not use Hyperthreading, it maybe reporting to the OS that does it by default. This would have an impact in performance scaling as well as power consumption as load increases.MrSpadge - Tuesday, November 15, 2011 - link
They are integer cores, which share few ressources besides the FPU. On the Intel side there are two threads running concurrently (always, @Stuka87) which share a few less ressources.Arguing which one deserves the name "core" and which one doesn't is almost a moot point. However, both designs are nto that different regarding integer workloads. They're just using a different amount of shared ressources.
People should also keep in mind that a core does not neccessaril equal a core. Each Bulldozer core (or half module) is actually weaker than in Athlon 64 designs. It got some improvements but lost in some other areas. On the other hand Intels current integer cores are quite strong and fat - and it's much easier to share ressources (between 2 hyperthreaded treads) if you've got a lot of them.
MrS
leexgx - Wednesday, November 16, 2011 - link
but on Intel side there are only 4 real cores with HT off or on (on an i7 920 seems to give an benefit, but on results for the second gen 2600k HT seems less important)where as on amd there are 4 cores with each core having 2 FP in them (desktop cpu) issue is the FPs are 10-30% slower then an Phenom cpu clocked at the same speed
anglesmith - Tuesday, November 15, 2011 - link
which version of windows 2008 R2 SP1 x64 was used enterprise/datacenter/standard?Lord 666 - Tuesday, November 15, 2011 - link
People who are purchasing SB-E will be doing similar stuff on workstations. Where are those numbers?Kevin G - Tuesday, November 15, 2011 - link
Probably waiting in the pipeline for SB-E base Xeons. Socket LGA-2011 based Xeon's are still several months away.Sabresiberian - Tuesday, November 15, 2011 - link
I'm not so sure I'd fault AMD too much because 95% of the people that their product users, in this case, won't go through the effort of upgrading their software to get a significant performance increase, at least at first. Sometimes, you have to "force" people to get out of their rut and use something that's actually better for them.I freely admit that I don't know much about running business apps; I build gaming computers for personal use. I can't help but think of my Father though, complaining about Vista and Win 7 and how they won't run his old, freeware apps properly. Hey, Dad, get the people that wrote those apps to upgrade them, won't you? It's not Microsoft's fault that they won't bring them up to date.
Backwards compatibility can be a stone around the neck of progress.
I've tended to be disappointed in AMD's recent CPU releases as well, but maybe they really do have an eye focused on the future that will bring better things for us all. If that's the case, though, they need to prove it now, and stop releasing biased press reports that don't hold up when these things are benched outside of their labs.
;)
JohanAnandtech - Tuesday, November 15, 2011 - link
The problem is that a lot of server folks buy new servers to run the current or older software faster. It is a matter of TCO: they have invested a lot of work into getting webapplication x.xx to work optimally with interface y.yy and database zz.z. The vendor wants to offer a service, not a the latest technology. Only if the service gets added value from the newest technology they might consider upgrading.And you should tell your dad to run his old software in virtual box :-).
Sabresiberian - Wednesday, November 16, 2011 - link
Ah I hadn't thought of it in terms of services, which is obvious now that you say it. Thanks for educating me!;)
IlllI - Tuesday, November 15, 2011 - link
amd was shooting to capture 25% of the market? (this was like when the first amd64 chips came out)