Physical Memory vs. Swap Memory

[Clifton Smith]

Currently running HP-UX 11i on an HP9000/L-3000 5x. We have one instance of Oracle 8.1.7.2 running with approximately 200-225 concurrent users. What we are noticing is that swap memory is being utilized even though physical memory is only being utilized at about 69%. Is there a tuneable parameter which will cause the machine to fully utilize available memory before going out to swap?

[Bill Hassell]

This isn't actual swapping. It is an artifact of the way in which memory mapped files are handled. You can verify that nothing is being paged (swapped) out with vmstat (the po column) or with Glance (the m window, look at Page out).

NOTE: vmstat and Glance both report page in based on what the kernel reports--and the kernel treats the startup of a program as page in, as well as returning programs from the swap area. Ignore page in values for swap measurements.