The document discusses benchmark testing of OpenFOAM tutorials using different compilers and optimization options on two systems. It is found that using the Intel compiler with options -axAVX,SSE4.2 (-xSSE4.2) performs similarly but is faster than -xHost. The GNU compiler is around 15% slower than the Intel compiler.
5. 7200
5400
3600
1800
0
D system (Intel Xeon E5-2670 v2, 2.5GHz)
1.015 x
0 1800 3600 5400 7200
計算時間の比較 (Dシステム)
CPU time [s] (Case I3: Intel -xHost)
CPU time [s] (Case I1: Intel -axAVX,SSE4.2)
7200
5400
3600
1800
0
D system (Intel Xeon E5-2670 v2, 2.5GHz)
1.020 x
0 1800 3600 5400 7200
CPU time [s] (Case I2: Intel -xSSE4.2)
CPU time [s] (Case I1: Intel -axAVX,SSE4.2)
intelコンパイラでベクトル化オプションを変えても計算時間はほぼ変らない
5
OpenCAE Local Workshop@Kansai 20th Sep 2014 Masashi Imano (OCAEL Co. Ltd.)
6. 計算時間の比較 (Aシステム)
7200
5400
3600
1800
0
A system (Intel Xeon L5640, 2.26GHz)
0.995 x
0 1800 3600 5400 7200
CPU time [s] (Case I2: Intel -xSSE4.2)
CPU time [s] (Case I1: Intel -axAVX,SSE4.2)
intelコンパイラでベクトル化オプションを変えても計算時間はほぼ変らない
6
OpenCAE Local Workshop@Kansai 20th Sep 2014 Masashi Imano (OCAEL Co. Ltd.)
7. intel vs gnu
7200
5400
3600
1800
0
D system (Intel Xeon E5-2670 v2, 2.5GHz)
1.147 x
0 1800 3600 5400 7200
CPU time [s] (Case G2: gnu -O3)
CPU time [s] (Case I1: Intel -axAVX,SSE4.2)
7200
5400
3600
1800
0
A system (Intel Xeon L5640, 2.26GHz)
1.154 x
0 1800 3600 5400 7200
CPU time [s] (Case G2: gnu -O3)
CPU time [s] (Case I1: Intel -axAVX,SSE4.2)
intel版に対するgnu版の計算時間の回帰式の係数は1.15で15%の増加
OpenCAE Local Workshop@Kansai 20th Sep 2014 7 Masashi Imano (OCAEL Co. Ltd.)