Large amount of buffer cache

[James Rigger]

I posted a similar question several days ago and am not sure of my success.
I am a new usenet user an may have fouled up - soffr if so.

I am encountering a system which has 128 meg of 256 devoted to buffer cache.
The system is running HP-UX 7.xx and has mirrored disks.  Does anyone know
of possible performance issues due to such a large pool of cache?  Will
such a large amount of cache cause the cache searches to wind up slower
than requesting disk to feed the information to a smaller pool?