Performance hit for increasing pt_cnt?

Solaris 2.x on Ultra 80’s (1GB memory, 2-way). Systems used for application development and testing. Originally pt_cnt = 48 in /etc/system I believe, and I’ve had to keep increasing monthly up to 1800 last week and we’re still running out of session resources. I bumped it up to 3200 but I’m wondering what effect this is having on the system. What are the downsides and performance hit to this. What if I just set it at 10,000?

Thanks,
David