Wednesday Nov 15, 2006
Woodcrest scaling issues? Yes, remember scaling is critical for
system performance, so don't look too much at single core performance or single job performance as it can lead to the wrong conclusions. In fact Sun's Opteron scaling means that the Sun systems can outperform Woodcrest by 18% to 22% as shown below.
On a 4 core/2chip
Intel Woodcrest systems they are only seeing 2.8x to 2.9x on 4 cores -- this doesn't bode well for quad-core or larger systems made out of these. Sun sees 3.6x to 4.1x scaling in the table below. Couple this with the high-wattage of these Woodcrest (31-Oct posting) and Woodcrest may have issues?
Opteron leads poor Woodcrest scaling & performance on Fluent 6 Benchmark (Both systems 2 sockets and using dual-core)
| System |
GHz/Chip |
#cores |
FL5M3 (scaling) |
FL5L2 (scaling) |
| INTEL S5000XAL |
3.0GHz Xeon Woodcrest 5160 |
4-core |
827.0 (2.8x) |
400.0 (2.9x) |
| INTEL S5000XAL |
3.0GHz Xeon Woodcrest 5160 |
2-core |
553.7 (1.9x) |
226.0 (1.6x) |
| INTEL S5000XAL |
3.0GHz Xeon Woodcrest 5160 |
1-core |
297.3 (1.0x) |
138.0 (1.0x) |
| Sun |
| Sun X4100 M2 |
2.8GHz Opteron DC 2200 |
4-core |
979.9 (3.6x) |
486.6 (4.1x) |
| Sun X4100 M2 |
2.8GHz Opteron DC 2200 |
2-core |
516.1 (1.9x) |
241.8 (2.1x) |
| Sun X4100 M2 |
2.8GHz Opteron DC 2200 |
1-core |
273.5 (1.0x) |
117.6 (1.0x) |
Rating = No. of sequential runs of test case possible in 1 day,
86,400/(Total Elapsed Run Time in Seconds)
Fluent results at:
http://www.fluent.com/software/fluent/fl5bench/flbench_6.2/fullres.htm
...I suspect even better performance and scaling on Sun Fire X4100 M2
with Solaris...
Friday Nov 03, 2006
Does the Woodcrest have scaling issues now? It may be caused by the rush
to increase core count without really considering design. On a 4 core/2chip
Intel Woodcrest systems we are only seeing 3.0x to 3.3x on 4 cores -- this doesn't bode well for quad-core or larger systems made out of these. Couple this with the high-wattage of these chips (Tuesday's posting) and this chip may have issues?
Poor Woodcrest scaling & Performance on Fluent 6 Benchmark
| System |
GHz/Chip |
#cores |
FL5L1 (scaling) |
FL5L2 (scaling) |
| INTEL S5000XAL |
3.0GHz Xeon Woodcrest 5160 |
4-core 2-Socket |
631.8 (3.3x) |
400.0 (3.0x) |
| INTEL S5000XAL |
3.0GHz Xeon Woodcrest 5160 |
2-core 1-Socket |
372.8 (1.9x) |
226.0 (1.7x) |
| INTEL S5000XAL |
3.0GHz Xeon Woodcrest 5160 |
1-core |
194.0 (1.0x) |
133.0 (1.0x) |
Rating = No. of sequential runs of test case possible in 1 day,
86,400/(Total Elapsed Run Time in Seconds)
Fluent results at:
http://www.fluent.com/software/fluent/fl5bench/flbench_6.2/fullres.htm
Thursday Nov 02, 2006
Woodcrest having issues scaling with GHz? On the
SPECfp_rate2000 result website, when Woodcrest goes from 2 GHz to 3 Ghz (50% clock increase), but the SPECfpRate only adds 17.8%. Not good, is it?
| System |
Chip/GHz |
Config |
Score |
| Fujitsu Siemens CELSIUS R540 |
5160 3.0 GHz |
4-core 2-Socket |
80.6 |
| Fujitsu Siemens CELSIUS R540 |
5150 2.66 GHz |
4-core 2-Socket |
77.4 |
| Fujitsu Siemens CELSIUS R540 |
5130 2.0 GHz |
4-core 2-Socket |
68.4 |
I'm thinking memory latency is an issue? Tomorrow, I'll look at scaling
as you add cores, maybe an issue there?
Disclosure
Fujitsu Siemens CELSIUS R540 2.0GHz (2chips,4cores), 68.4 SPECfp_rate2000, Fujitsu Siemens CELSIUS R540 2.66GHz (2chips,4cores), 77.4 SPECfp_rate2000, Fujitsu Siemens CELSIUS R540 3.0GHz (2chips,4cores), 80.6 SPECfp_rate2000.
SPEC, SPECint reg tm of Standard Performance Evaluation Corporation. Results from www.spec.org as of 11/2/06.
It will get even worse with the "quad core" Clover...