pages_pp_maximum Parameter

Description

Defines the number of pages that must be unlocked. If a request to lock pages would force available memory below this value, that request is refused.

Data Type

Unsigned long

Default

The greater of (tune_t_minarmem + 100 and [4% of memory available at boot time + 4 MB])

Range

Minimum value enforced by the system is tune_t_minarmem + 100. The system does not enforce a maximum value.

Units

Pages

Dynamic?

Yes, unless dynamic reconfiguration operations that add or delete memory occur. At that point, the value is reset to the value provided in /etc/system.d/file or was calculated from the new physical memory value.

Validation

If the value specified in a file in the /etc/system.d directory or the calculated default is less than tune_t_minarmem + 100, the value is reset to tune_t_minarmem + 100.

No message is displayed if the value from a /etc/system.d/file file is increased. Validation is done only at boot time and during dynamic reconfiguration operations that involve adding or deleting memory.

When to Change

When memory-locking requests fail or when attaching to a shared memory segment with the SHARE_MMU flag fails, yet the amount of memory available seems to be sufficient.

Excessively large values can cause memory locking requests (mlock, mlockall, and memcntl) to fail unnecessarily. For more information, see the mlock(3C), mlockall(3C), and memcntl(2) man pages.

Commitment Level

Unstable