I taked a test to find how many processors is best in roms running, this result is that the fastest running when I used 12 processors in one node;processor : 0
vendor_id : GenuineIntel
cpu family : 6
model : 44
model name : Intel(R) Xeon(R) CPU E5645 @ 2.40GHz
stepping : 2
cpu MHz : 2527.000
cache size : 12288 KB
the next is used less than 12 processors;
but others are very slow, such as the number of used cores more than 12 processors in one node or used 12 processors in differents nodes.
Please tell me why will appear this kind of situation?