Payslip generation takes long time

Hi Experts

I have a issue of generation of payslip takes a long time. In one of my client, there are around 35000 employees all under one payroll area, they run the payslip program in the background. This current month it took 30 hrs to complete. as we analysed we came to know it goes retro upto 8 - 10 months for many employees.

Is there any option to speedup the process?

Regards

Anto