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In Tests Opteron Shows Efficiency Edge Over Intel, Again
Ted Samson writes "In their latest round of energy-efficiency tests between AMD Opteron and Intel Xeon, independent testing firm Neal Nelson and Associates find AMD still holds an edge, but it's certainly not cut-and-dried. Nelson put similarly equipped servers through another gauntlet of tests, swapping in different amounts of memory and varying transaction loads. In the end, he found that the more memory he installed on the servers, the better the Opteron performed compared to the Xeon. Additionally, at maximum throughput, the Intel system fared better, power-efficiency-wise, by 5.0 to 5.5 percent for calculation intensive workloads. For disk I/O intensive workloads, AMD delivered better power efficiency by 18.4 to 18.6 percent. And in idle states — that is, when servers were waiting for their next work load — AMD consistently creamed Intel."
Opteron?
Xeon?
Why do these top of the line processors sound like character names from crummy 1980-vintage cartoons about giant robots who talk like street thugs?
"I'm calling you out Xeon! You will be defeated and all Processaria will bow before my superior power stats!"
"You're a fool if you believe those benchmarks Opteron! The true power is Inside!" (duh-Dah-dumm!)
This just in! AMD is more efficient than Intel when doing nothing!
For a really good test, they should compare AMD to an empty carboard box, and see which one uses more power when processing no transactions.
Even if its not cut and dry, this is EXCELLENT for the CPU industry. We need to see competition between the manufacturers.
Don't let that get lost in the arguments between which is better or what have you. Continued improvements and development benefits everyone.
Here is the whitepaper, instead of the summaries.
"Further, in cases where Intel outperformed AMD in power efficiency, the servers were configured with smaller larger memory sizes."
It's all so clear dark to me now...
Xeon 51xx (Woodcrest) is essentially the same as Core 2 Duo (Conroe); it is very power-efficient.
Depends on the rest of the specs. If you have a muscle car with more power for less fuel, certainly it's worth noting.
More Twoson than Cupertino
The submitted article is terrible. The full paper is much more informative. For example, the full paper gives the system specs (both systems at 3.0GHz) and shows that the Opteron system is much cheaper ($2800 vs. $4170 for 2GB configuration).
Actually, if you look at the raw test data (rather than the conclusions) you will see that both servers performed nearly equally. The xeon doing slightly better on some tests, while the opteron better in others. In most tests the results are about the same (5% difference)
Amazingly skimpy article. No effing data whatsoever.
I can bet a case of beer that this was run in a standard server config under Winhoze Server 2003. These are the results you more or less expect in that case.
If that is the case neither Opteron, nor Xeon utilise CPU frequency scaling as there is no OS support. If you use CPU frequency scaling under let's say current RHEL or Debian, the idle and IO efficiency picture tends to reverse because AMD is still not as good at this as Intel. In fact it not even supported on many server BIOSes/Motherboards.
As a result even if supported (and it usually isn't) AMD power utilisation with reduced frequency in idle is higher than that of a Xeon system which consumes nearly nothing when you slam it down to 250MHz. If the OS drops and ramps up the CPU frequency correctly Intel should win on idle and IO-only benchmarks.
Not that it matters in the slightest as AMD will cream it on most real life loads anyway due to better memory and IO bandwidth.
Baker's Law: Misery no longer loves company. Nowadays it insists on it
http://www.sigsegv.cx/
No, the point is people are starting to care about the total power usage of their 500-zillion server colo facility, where even a 5% reduction in power usage can mean hundreds or thousands on the power bill.
In gas usage? Probably. Which matters, especially if you do a lot of city or stop-and-go driving. ;)
Eternity is a time bomb.
A file server or webserver doing static pages, sure. A computation server or server doing lots of dynamic content, not so much. A more useful benchmark would be to measure the actual loads for various tasks, then see how they perform for that. Say "If you have a server doing X, this is what you can expect form these processors." Servers aren't a "one size fits all" kind of deal. I agree idle efficiency is something worth considering but let's not pretend like all servers just idle. Also, I know many places are like us in that the more a server idles, the older the server that tends to go there. We don't have much acting as your LDAP servers, but then we don't need it. However our computation servers are rather powerful, and loaded almost 24 hours a day.
The point of the study is the relative power efficiency of the two processors, not absolute power efficiency. If you need the performance of an Opteron or Xeon, why wouldn't you choose the more efficient one (all else being equal)?
Nope. Muscle cars are about power. If you car has more power and less fuel, you win. If your car has more power and more fuel, then you win.
It's not even worth noting.
Now if you are talking about high performance race cars, then it is pretty important.
The Kruger Dunning explains most post on
http://www.worlds-fastest.com/d.pdf/wfw991.pdf
(Granted, it was buried several links deep.)
The article does not mention it, but SLES 10 enables cpufreq and the ondemand governor by default.
AMD power utilisation with reduced frequency in idle is higher than that of a Xeon system which consumes nearly nothing when you slam it down to 250MHz.
Uh, the lowest frequency of the Xeon 5160 is 2GHz.
It's all about performance per watt. Well, and other considerations, like how much the hardware costs up front, and how much physical space it will require.
The bottom line is: You want to spend your money in the most efficient way possible.
If you have two potential architectures, and one offers more performance per watt, then ignoring up front hardware costs, it's cheaper to run the one that costs you less power. That's a bit different than suggesting they just use a bunch of laptop CPUs.
Don't thank God, thank a doctor!
If you fully load them down, my X2s use nearly as much as the Core2 systems - but when lightly loaded, my experience mirrors that of the article, that the X2 systems use significantly less power.
In our call center, we built a large batch of X2-based systems - nothing too fancy, just an X2/3800, two gigs of memory, a 250-gig drive, a DVD burner, a 6200tc video card, and 19" LCD monitors. The cases and power supplies were pretty cheap - I think $35 for the case and a "400-watt" power supply. (Yes, the quotes are there for a reason.)
In order to size out the UPS units, we broke out the old, trusty Kill-A-Watt. In logging into a PDC server, browsing the web, checking email, etc., then logging out, the peak draw for one machine and monitor together was 140 watts, with the load *most* of the time at 80-100 watts. Those are some spankily low numbers, especially when you consider that the monitor's contribution was probably 25-40 watts.
And, as we speak, I have a dual-socket, dual-core opteron with a 15K SCSI raid array and 8 gigs running just a few feet away from me, with 4 instances of Prime95 running. Kill-A-Watt says 296 watts with all of that going on. This is going to replace an old 4x700 MHz Xeon server which draws 500-700 watts. The power factor, however, is just 0.7 - I really need a better power supply in there.
Oh, you're not stuck, you're just unable to let go of the onion rings.
Over and over again people try and compare the efficiencies between two "seemingly" identical servers / machines. But truly, how can you declare a winner (and base it on something like a 5% efficiency margin) when the two machines are using different power supplies? A 600 Watt for the Intel, 500 Watt for the AMD. I can't find those models listed on Delta's website at quick glance, but it'd be a stretch to imagine that two different power supplies have the exact same efficiency curves. I mean, I'd believe if they were accurate to within maybe 3%, so now we're arguing over whether or not Intel and AMD are more than 2% different in efficiency? Come on people. The whitepaper does say they assume there might be a 1% difference between the two power supplies, but that's based on "eyeballing" the efficiency curves.
We know that Intel takes a hit with FB-DIMM memory especially as you add more memory modules.
Another inconsistency appears to be related to the case design, where the cases for the Intel machines appeared to be providing inadequate cooling for the memory modules, causing the system management controller to bump up fan speed considerably. So now we're comparing two systems with different power supplies and with different requirements for cooling which may or may not be related to the actual architecture but may be impacted by a design consideration made by the case manufacturer. How would these results change with different power supplies or a different case. Are the differences the same in a 2U case? A tower? Does it get worse? Better? I know that our Mac Pro's NEVER speed up the fans above the 500/600 RPM's that they bottom out at.
As noted by others, the paper is completely devoid of any discussion regarding CPU frequency / voltage scaling that may or may not be handled by the BIOS or Linux resident programs (cpuspeed daemon). It's possible they haven't even checked for it. As our company has both Intel and AMD linux boxes, I can testify that linux is very sensitive to motherboard/cpu combinations when it comes to cpu scaling and it's "possible" that this could be playing a MAJOR role in the idle performance values. It'd be nice to see it addressed.
Lastly, there's no discussion as to the optimizations made to the software being run on each of the boxes. Is the code compiled for each architecture individually taking into account support for 3DNow / SSE instructions, cache sizes, etc? Obviously more efficient or less efficient code execution would have a MAJOR impact on these studies, enough so that companies usually spend a large amount of time playing with compiler options to get the best performance on a given architecture. And when you're arguing over performance comparisons in the sub 20% difference arena, code efficiency should be addressed, especially if it's not a big commercial package that "everyone" in the industry would be using. Anyhoo, just my thoughts.
I don't fully agree with the parent post, but it's not a troll. Some of these are legitimate issues.
there's no discussion as to the optimizations made to the software being run on each of the boxes. Is the code compiled for each architecture individually taking into account support for 3DNow / SSE instructions, cache sizes, etc? Obviously more efficient or less efficient code execution would have a MAJOR impact on these studies, enough so that companies usually spend a large amount of time playing with compiler options to get the best performance on a given architecture.
In the real world, people use the binaries that are provided by the distro, which is also what was done in this test. Apache and MySQL are not particularly amenable to compiler optimization anyway.
It's the people buying the things they are appealing to. It's your intelligence they're insulting.
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