Intel Woodcrest, AMD's Opteron and Sun's UltraSparc T1: Server CPU Shoot-out
by Johan De Gelas on June 7, 2006 12:00 PM EST- Posted in
- IT Computing
The Official SPEC Numbers
SPEC FP and Int 2000 are the standard benchmarks to evaluate CPU performance. However, the benchmark numbers are highly dependant on the compiler. SPEC fp and Integer show the best case performance as the CPU runs on the aggressively compiled and highly optimized code. In the real world, code is compiled in a more conservative/less optimized way.
In practice this means that Intel's SPEC numbers - thanks to it's highly capable compiler team - are (slightly) higher than in real applications. Nevertheless, SPEC CPU 2000 is a good starting point to understand what a CPU is capable off. As mentioned earlier, the Xeon 5100 is the Xeon Woodcrest, based on the new core architecture.
The new Woodcrest is about 20-25% faster than the fastest dual-core Opteron. The 7% clockspeed advantage is most likely a result of the fact that the Woodcrest was baked with a newer 65nm process. If AMD manages to keep up with Intel when it comes to clockspeed, the advantage of their newest CPU might shrink to 15% or less. However, Intel's Woodcrest will have a much bigger advantage in all applications that make heavy use of 64 and 128-bit SSE.
When it comes to integer performance, the Woodcrest numbers are simply stunning and vastly superior to any other architecture. Let us find out if this vastly superior integer performance in SPEC Int 2000 pays off in server applications.
Latencies...
LMBench is a set of micro-benchmarks which can be helpful for determining memory latency and instruction latencies. We tested with LMBench 3.0a-5. It must be said that LMBench is usually right, but not always. If the benchmark is not aware of some of the particularities of a certain architecture, it can measure wrong values. So we have to double check if the values measured make sense.
The massive 4 MB L2 cache has an amazingly low latency of 14 cycles. This seems to be the worst case, as we have measured 12 cycles with other benchmarking tools such as ScienceMark. Nevertheless, even 14 cycles at 3 GHz is pretty amazing. The Core Duo, a.k.a. Yonah, accesses a shared cache that's half as large in 14 cycles at a substantially lower 2.33 GHz.
On the other hand, the memory latency very high; luckily the 4 MB L2 cache will minimize that effect. The problem seems to be the FB-DIMMs. The Advanced Memory Buffer introduces extra latency, and of course the registered DDR-2 533 chips with a CAS latency of 4 have a higher latency by themselves. This results in a memory subsystem with pretty high 115 ns latency, while the Opteron has access to the RAM in only 73 ns
ScienceMark didn't agree completely and reported about 65-70 ns latency on the Opteron system and 70-76 ns (230 cycles) on the Woodcrest system. We have reason to believe that Woodcrest's latency is closer to what LMBench reports: the excellent prefetchers are hiding the true latency numbers from Sciencemark. It must also be said that the measurements for the Opteron on the Opteron are only for the local memory, not the remote memory.
SPEC FP and Int 2000 are the standard benchmarks to evaluate CPU performance. However, the benchmark numbers are highly dependant on the compiler. SPEC fp and Integer show the best case performance as the CPU runs on the aggressively compiled and highly optimized code. In the real world, code is compiled in a more conservative/less optimized way.
In practice this means that Intel's SPEC numbers - thanks to it's highly capable compiler team - are (slightly) higher than in real applications. Nevertheless, SPEC CPU 2000 is a good starting point to understand what a CPU is capable off. As mentioned earlier, the Xeon 5100 is the Xeon Woodcrest, based on the new core architecture.
| SPECfp | ||
| Clockspeed | SPEC fp 2000 | |
| POWER5+ | 2200 | 3271 |
| Itanium 2 | 1666 | 2851 |
| Xeon 5160 | 3000 | 2783 |
| Opteron | 2800 | 2256 |
| Pentium 4 E | 3733 | 2232 |
The new Woodcrest is about 20-25% faster than the fastest dual-core Opteron. The 7% clockspeed advantage is most likely a result of the fact that the Woodcrest was baked with a newer 65nm process. If AMD manages to keep up with Intel when it comes to clockspeed, the advantage of their newest CPU might shrink to 15% or less. However, Intel's Woodcrest will have a much bigger advantage in all applications that make heavy use of 64 and 128-bit SSE.
| SPECint | ||
| Clockspeed | SPEC Int 2000 | |
| Xeon 5160 | 3000 | 3057 |
| Pentium 4 E | 3733 | 1870 |
| Opteron | 2800 | 1837 |
| Pentium 4 Xeon | 3733 | 1813 |
| POWER5+ | 2200 | 1705 |
| Itanium 2 | 1666 | 1502 |
When it comes to integer performance, the Woodcrest numbers are simply stunning and vastly superior to any other architecture. Let us find out if this vastly superior integer performance in SPEC Int 2000 pays off in server applications.
Latencies...
LMBench is a set of micro-benchmarks which can be helpful for determining memory latency and instruction latencies. We tested with LMBench 3.0a-5. It must be said that LMBench is usually right, but not always. If the benchmark is not aware of some of the particularities of a certain architecture, it can measure wrong values. So we have to double check if the values measured make sense.
| LMBench | |||||||
| Clockspeed | L1 (ns) | L1 (cycles) | L2 (ns) | L2 (cycles) | RAM (ns) | RAM (cycles) | |
| Xeon 5160 3 GHz | 3000 | 1.01 | 3 | 4.7 | 14 | 117.3 | 345 |
| Pentium- M 1.6 GHz | 1593 | 2 | 3 | 6 | 10 | 92.1 | 147 |
| Sun T1 1 GHz | 980 | 3 | 3 | 22.1 | 22 | 107.5 | 105 |
| Opteron 275 | 2209 | 1 | 3 | 5.5 | 12 | 73 | 161 |
| Xeon Irwindale 3.6 GHz | 3594 | 1 | 4 | 8 | 28 | 48.8 | 175 |
The massive 4 MB L2 cache has an amazingly low latency of 14 cycles. This seems to be the worst case, as we have measured 12 cycles with other benchmarking tools such as ScienceMark. Nevertheless, even 14 cycles at 3 GHz is pretty amazing. The Core Duo, a.k.a. Yonah, accesses a shared cache that's half as large in 14 cycles at a substantially lower 2.33 GHz.
On the other hand, the memory latency very high; luckily the 4 MB L2 cache will minimize that effect. The problem seems to be the FB-DIMMs. The Advanced Memory Buffer introduces extra latency, and of course the registered DDR-2 533 chips with a CAS latency of 4 have a higher latency by themselves. This results in a memory subsystem with pretty high 115 ns latency, while the Opteron has access to the RAM in only 73 ns
ScienceMark didn't agree completely and reported about 65-70 ns latency on the Opteron system and 70-76 ns (230 cycles) on the Woodcrest system. We have reason to believe that Woodcrest's latency is closer to what LMBench reports: the excellent prefetchers are hiding the true latency numbers from Sciencemark. It must also be said that the measurements for the Opteron on the Opteron are only for the local memory, not the remote memory.
Facebook
Twitter
RSS
91 Comments
View All Comments
rayl - Thursday, June 8, 2006 - link
"Best Performance/Watt in the high end "Which part of performance per watt do you not understand? Do more, pay less.
MrKaz - Thursday, June 8, 2006 - link
Dual Opteron 275 HE 2CPU's (275HE) - 4 GB RAM 192 Watts!!!Dual Opteron 275 2CPU's - 4 GB RAM 239 Watts!!!
Dual Xeon 5160 3 GHz 2 CPU's - 4 GB RAM 245 Watts!!!
http://www.intel.com/performance/server/xeon/ppw.h...">http://www.intel.com/performance/server/xeon/ppw.h...
Even Intel numbers show Xeon 3.6Ghz on par with AMD (obvious fake)
And the do more pay less, is not like you say on the server market, while your PC is doing lot of work (processing) with a computer game, most servers stand there doing almost nothing. Our servers for example from 0:00 to 8:00 do almost zero. Even in the day they work very little. Our Xeon 2.4 is more than enough, and I think most people think the same. Of course this depends a lot what you do, but this is generic. I think you know why virtualization is very important right?
rayl - Thursday, June 8, 2006 - link
Isn't this obvious to you. Those are power consumption numbers at 100% CPU load. This is where performance/watt number really matters.If you're running idle, the power saving mode starts kicking in, you'll need a separate table to draw your conclusion.
Why this preoccupation with power consumption? 6-watts for a performance leap; it's moot.
coldpower27 - Thursday, June 8, 2006 - link
It will be interesting to note the Delta difference between 1 Woodcrest 5160 and 2 is 59W as reported by TechReport, and since the TDP for Woodcrest 5160 is 80W TDP we can extrapolate and since the TDP for Woodcrest 5148 is 40W I can expect it to spew about 30W per processor.
245W - (2x29W) = 187W
This bring the Low Power Woodcrest system to ~ the same power usage as the HE Opteron 275's even with the heat spewing FB-DIMM's with higher performance per watt, pretty impressive.
Questar - Thursday, June 8, 2006 - link
Yeah I'm worried about those six watts of power when I'm getting twice the performace.fikimiki - Thursday, June 8, 2006 - link
You forgot about Intel chipset consumption - 22 Watts.So Intel has 245+22=267 vs. 192 and even if you are running in power-saving mode, chipset is running all the time...
coldpower27 - Thursday, June 8, 2006 - link
No Wrong, they measured the system power consumption hence why the Woodcrests systems are so hungry in comparison to the Opteron the FB-DIMM's are what eating away at the wattage.So in the end it's 223 + 22 = 245, if indeed the chipset is consuming 22W.
Questar - Thursday, June 8, 2006 - link
That was system power consumption - it included the chipset dufus.Saist - Wednesday, June 7, 2006 - link
I amd going to make the argument that evaluating only one version of Linux in this type of situation is not a good idea in and of itself. Not to knock Gentoo directly, it is a fine distro to itself, but it has a very small slice of the Linux market. It would have made more sense for Anandtech to have benchmarked using other distrobution types for a couple of reasons.The first reason is the ability to duplicate the tests. This is actually a strike against Gentoo for what the operating system is. While it possible to duplicate an installation of Gentoo and the applications used, generating an exact copy of the exact configuration used without clear description of the compile targets used is very hard. This means that anybody wishing to reproduce these results on their own will be very hard-pressed to do so.
The second reason is commercial and residential use. Gentoo has it's market, that market just isn't very widespread. It would have made more sense for Anandtech to have tested a RPM based distro such as Mandriva, RedHat, Fedora Core, Novell Suse, or OpenSuse against a .deb based distro such as Debian(sid), Ubuntu, Mepis, or Xandros. The reason why it would have made more sense is that .deb and .rpm distros are actually used in the commercial and residential spheres, and used in great quantities. Had Anandtech used a distrobution that is in active use it would mean more to buyers currently looking to replace their Windows computers with a new system.
It would only be in the interests in providing a point of perspective that one would test a different type of Linux distrobution like Gentoo or Slackware.
Going back to the first point, had Anandtech benchmarked these on a Debian based system it would be fairly easy to duplicate the tests. Anandtech would just need to list the base version of the Debian distro they used, list the apt-repositories they pulled from, and the application in apt that were pulled. Anybody else who comes along afterwords with a Debian based distro would easily be able to duplicate the steps and the benchmarks.
The overall point is that while it is nice to see a non-dedicated Linux site approaching hardware, this isn't the way to approach it. As it stands now, the Anandtech tests are useless, reguardless of whatever results the benchmarks returned.
BasMSI - Thursday, June 8, 2006 - link
These tests are also 100% useless.....The MSI K2-102 is numa aware....
But for some reason the K8N-Master isn't shown in the graphs....that board is NOT NUMA aware.
I'm also missing the HP server everywhere in the graphs.
I realy believe all these tests are done on the K8N-Master board for all Opteron tests.
No way the graphs are showing all the systems.
These tests are a total fraude, letting us believe Intel all of a sudden became that fast.
No way on earth I believe any of these results.
Also, why using Gentoo? Why not Debian 64bit?
This puzzles me, as Gentoo is compiled but not known to be faster on every system.
Why not using precompiled Linuxes? Like Debian 64bit....that one is stable as hell and incredible fast!
Too much parameters missing here to get any judgement at all.
Do it better, this is 100% rubbish.
Bas.