Intel's Pentium Extreme Edition 955: 65nm, 4 threads and 376M transistors
by Anand Lal Shimpi on December 30, 2005 11:36 AM EST- Posted in
- CPUs
Multi-core support in Games?
Both Quake 4 and Call of Duty 2 now have SMP support, supposedly offering performance improvements on dual core and/or Hyper Threading enabled processors.
For Call of Duty 2, you simply install the new patch and off you go; SMP support is enabled. To verify, we ran our CoD 2 benchmark and kept a log of the total processor utilization over time. Below is a shot of perfmon with a fresh install of CoD2 (sans SMP patch):
Now, let's look at CoD2 CPU utilization with the SMP patch installed:
We looked at performance at 1024x768 and obviously the higher the resolution, the lesser the impact of a faster CPU (at the same time, the lower the resolution, the greater the impact will be as the game becomes less GPU limited).
To ensure a fair comparison, we tested using the SMP patch and simply disabled SMP manually by setting the r_smp_backend variable to "0". We confirmed that SMP support was actually disabled by running perfmon and measuring CPU utilization.
Surprisingly enough, we actually saw pretty large performance drops in CoD2 with SMP enabled across both AMD and Intel platforms. This is unfortunate, but the withdrawn SMP support of Quake 3 makes it less than shocking. We do expect that things will get better as time goes on.
Quake 4 was a different story; with r_useSMP enabled, we saw some extremely large performance gains with the move to dual core:
The SMP patch either only spawns two threads, or the instruction mix of Quake 4 with the patch does not mix well with Intel's Pentium EE 955. The dual core with Hyper Threading enabled platform didn't do anything at all for performance.
While we're only looking at two games, this is a start for multithreaded game development. You can expect to see a lot of examples where dual-core does absolutely nothing for gaming, but as time goes on, the situation will change.
Both Quake 4 and Call of Duty 2 now have SMP support, supposedly offering performance improvements on dual core and/or Hyper Threading enabled processors.
For Call of Duty 2, you simply install the new patch and off you go; SMP support is enabled. To verify, we ran our CoD 2 benchmark and kept a log of the total processor utilization over time. Below is a shot of perfmon with a fresh install of CoD2 (sans SMP patch):
Now, let's look at CoD2 CPU utilization with the SMP patch installed:
We looked at performance at 1024x768 and obviously the higher the resolution, the lesser the impact of a faster CPU (at the same time, the lower the resolution, the greater the impact will be as the game becomes less GPU limited).
To ensure a fair comparison, we tested using the SMP patch and simply disabled SMP manually by setting the r_smp_backend variable to "0". We confirmed that SMP support was actually disabled by running perfmon and measuring CPU utilization.
| Call of Duty 2 | SMP Disabled | SMP Enabled |
| AMD Athlon 64 FX-57 (2.8GHz) | 80.6 | N/A |
| AMD Athlon 64 X2 4800+ (2.4GHz) | 79.8 | 70.3 |
| AMD Athlon 64 X2 3800+ (2.0GHz) | 78.7 | 68.1 |
| Intel Pentium Extreme Edition 955 (3.46GHz) | 79.8 | 68.4 |
| Intel Pentium Extreme Edition 840 (3.2GHz) | 78.1 | 68 |
| Intel Pentium D 820 (2.8GHz) | 75.6 | 67.1 |
Surprisingly enough, we actually saw pretty large performance drops in CoD2 with SMP enabled across both AMD and Intel platforms. This is unfortunate, but the withdrawn SMP support of Quake 3 makes it less than shocking. We do expect that things will get better as time goes on.
Quake 4 was a different story; with r_useSMP enabled, we saw some extremely large performance gains with the move to dual core:
| Quake 4 | SMP Disabled | SMP Enabled |
| AMD Athlon 64 FX-57 (2.8GHz) | 115.4 | N/A |
| AMD Athlon 64 X2 4800+ (2.4GHz) | 114.9 | 147.4 |
| AMD Athlon 64 X2 3800+ (2.0GHz) | 100.9 | 143.2 |
| Intel Pentium Extreme Edition 955 (3.46GHz) | 98.9 | 142.3 |
| Intel Pentium Extreme Edition 840 (3.2GHz) | 89.0 | 133.6 |
| Intel Pentium D 820 (2.8GHz) | 80.6 | 125.5 |
The SMP patch either only spawns two threads, or the instruction mix of Quake 4 with the patch does not mix well with Intel's Pentium EE 955. The dual core with Hyper Threading enabled platform didn't do anything at all for performance.
While we're only looking at two games, this is a start for multithreaded game development. You can expect to see a lot of examples where dual-core does absolutely nothing for gaming, but as time goes on, the situation will change.
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Betwon - Saturday, December 31, 2005 - link
NO.Don't You think that Future versions of the patch will be written by intel.
Viditor - Saturday, December 31, 2005 - link
Doubtful (but who knows)...I can't see Intel spending 100s of millions with every developer (or even 1 developer) for the long term, just to keep tweaking their patches. It's just not a very smart long term strategy (and Intel is quite smart).
Betwon - Saturday, December 31, 2005 - link
You just guess it.We find that the good quality codes can provide better performance for both AMD and Intel.
Intel can often benefit more, because the performance potential of Intel is high.
Now, You can not find another SMP-game which can make fps of SMP CPU improve so much great.
If you find it, please tell us.
There is no one who found it.
Viditor - Saturday, December 31, 2005 - link
Now it's you who's guessing...
Betwon - Saturday, December 31, 2005 - link
NO.It is true.
Viditor - Saturday, December 31, 2005 - link
OK...prove it!
Betwon - Saturday, December 31, 2005 - link
For example:we saw a test(from anandtech)
With the good quality codes, AMD become faster than before, but Intel become much faster than before.
They use Intel's compiler.
Betwon - Saturday, December 31, 2005 - link
When not use the intel's compiler, AMD become slow.Viditor - Saturday, December 31, 2005 - link
I know you've often quoted from the spec.org site...
I suggest you revisit there and look at the difference between AMD systems using Intel compilers and the PathScale or Sun compilers. In general, the Spec scores for AMD improve by as much as 30% when not using an Intel compiler...especially in FP.
http://www.swallowtail.org/naughty-intel.html">http://www.swallowtail.org/naughty-intel.html
defter - Saturday, December 31, 2005 - link
This is not true, for example:
FX-57, Intel compiler, SpecInt base 1862:
http://www.spec.org/osg/cpu2000/results/res2005q2/...">http://www.spec.org/osg/cpu2000/results/res2005q2/...
FX-57, Pathscale compiler, 1745: http://www.spec.org/osg/cpu2000/results/res2005q2/...">http://www.spec.org/osg/cpu2000/results/res2005q2/...
Opteron 2.8GHz, Intel compiler, SpecInt base 1837: http://www.spec.org/osg/cpu2000/results/res2005q3/...">http://www.spec.org/osg/cpu2000/results/res2005q3/...
Opteron 2.8GHz, Sun compiler, SpecInt base 1660: http://www.spec.org/osg/cpu2000/results/res2005q4/...">http://www.spec.org/osg/cpu2000/results/res2005q4/...
In SpecFP Intel compiler produces slightly slower results, but the difference isn't 30%:
Opteron 2.8GHz (HP hardware), Intel compiler, SpecFP base 1805: http://www.spec.org/osg/cpu2000/results/res2005q3/...">http://www.spec.org/osg/cpu2000/results/res2005q3/...
Opteron 2.8GHz (HP hardware), Pathscale compiler, SpecFP base 2052: http://www.spec.org/osg/cpu2000/results/res2005q3/...">http://www.spec.org/osg/cpu2000/results/res2005q3/...
Opteron 2.8GHz (Sun hardware), Sun compiler, SpecFP base 2132: http://www.spec.org/osg/cpu2000/results/res2005q4/...">http://www.spec.org/osg/cpu2000/results/res2005q4/...
So let's see:
Intel vs Sun compiler:
- Intel complier is 10.7% faster in SpecINT
- Sun compiler is 18.1% faster in SpecFP
Intel vs Pathscale compiler:
- Intel compiler is 6.7% faster in SpecInt
- Pathscale compiler is 13.7% faster is SpecFP
It is quite suprising that Intel's compiler gives best results for AMD's processors in many situations.