we use cxcalc for generating conformations in a computer with 8 cpus. when cxcalc runs, use all of them at the begining ( almost 20 sec ) but after that the performance decrease to 1 cpu. you think, what is the problem? what is your opinion to solve it?
One processor calculates the conformers of one structure at a time, and the calculated structures are collected in an 'n' element queue before written to the output. (The 'n' structures will be out together.) We assume that the time to generate the conformers of one of your structure took more time than in the other 'n-1' cases/structures. Therefore, you could observe the working of only one processor as the other seven must have finished by that time.
According to this explanation, we think this behaviour is normal.