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Ed,
This is a classic memory hog problem with a lot of systems out there running HP-UX, where the kernel has not been customized. The default kernel settings allow the O-S to procure upto 50% of available memory for the file system buffer cache. This can and will cause severe memory starvation during times with very heavy load on the system. As a result of the memory starvation, the system will experience a significant amount of paging and swapping (in the H-P world it is also known by the term - process deactivation).
Been there in your shoes and it is not fun. The fix to this is to modify the relevant parameters (DBC...MIN and DBC...MAX ??) to 15%, so that no more than 15% of memory is allocated for the file system buffer cache. It is true even for systems that do not use raw devices. You can make these changes using the "SAM" utility.
Best Regards,
Gaja.
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