ONCONFIG Parameter SHMADD

I am on a Digital Unix box. The OS Vendor has told the maximum size of SHMVIRTSIZE the OS can be tuned to use is 2 Gig. All of the tuning manuals tell you to keep your Virtual Segments down to one (on HPUX) or two (all others) segments; after that, you will experience performance degradation. Now the roadblock: SHMADD has a MAXIMUM setting of 524,288 KB. Why? Our OS allows us to change the shared memory kernel parameter that (initially) contained the same value. Changing it had no effect (yeah, well it was worth a try). Due to both of the above maximums, we are now generating up to 5 extra virtual segments. Anyone know the reasoning behind both of these maximums, especially the hard-coded SHMADD maximum? Take care. Clifton Bean