Scheduling with infinite capacity is late

We checked the data.infinite capacity is assigned, but it took time to schedule.90,000 jobs took 40 minutes.
This is because too many jobs which have the same start time and the end time are assigned in one resource.
assignment as infinite capacity is also the reason. Too many jobs were piled with the same lead time in the place. When the other jobs are assigned after those jobs, it will take more time than usual.
That is because when a job is assigned, need to check the assembly with the job near it, which changeover(item setup .etc) will happen or not. When the jobs with the same start time are assigned, changeover need to be checked one by one.Even 1 second shiftting need not be checked. The data like this one which the jobs are assigned in same time, the changeover will be changed.
Checking with the assignment of the jobs. The number of the exponential will be plused. The data we had which the changeover is not be modified fortunately.We can modify”Scheduling parameter”-“Use changeover”to”no”, and the check will be omitted.
And the scheduling performance is about 3 minutes