HP-UX 11i Internals

Swap Priority

Both types of swap, device and file system, may be assigned a priority in the range of 0 to 10. Priority 0 devices are used first, and 10 are used last. The primary boot swap device is assigned a priority of 1, and if the priority is not specified to the swapon command, it assumes a default priority value of 1 as well. Device swap takes precedence over file system swap at the same priority, but file system swap at a stronger priority takes precedence over device swap at a weaker priority.

When two or more device or file system swap areas share the same priority, space is allocate from them in a round-robin fashion. This round-robin scheme is employed at the swap chunk level, not at the individual page level.