Maximum number of employee members in EPBCS Workforce module

We have enabled the OOB Workforce module in EPBCS. When we run HCM Integration, more than 250,000 employee members are being pulled into the EPBCS application.

I just wanted to check if there is any maximum number of employee members permitted in the Workforce module. We are testing out some OOB and custom rules and the performance is taking a hit. Sometimes, the whole application slows down to a halt.

Any help is appreciated!