HP-UX 11i September 2001 Release Notes

Process, Threads, Memory, and Kernel Parameters
Asynchronous Disk Pseudo Driver (async) Compatibility (new at 11i original release)
Chapter 8
137
Asynchronous Disk Pseudo Driver (async)
Compatibility (new at 11i original release)
The async driver is used mostly by databases for doing asynchronous I/O to the disk.
Applications that use the async driver must be owned by the superuser, or by a user who
is a member of a group for which the privileges include MLOCK.
To check a group’s privilege capabilities, issue this command:
/usr/bin/getprivgrp group_name
If the output of getprivgrp does not show that the group has the MLOCK privilege, set
the group’s privilege by issuing this command as root:
/usr/bin/setprivgrp <group_name> MLOCK
Impact
If the application accessing async driver is not owned by superuser or by a user who is a
member of a group that has MLOCK privilege, ASYNC_CONFIG and ASYNC_ADDSEG ioctl()
will fail and errno will be set to EPERM.
Compatibility
An application running on HP-UX 11.0 with patch PHKL_22126 installed will operate
correctly when upgraded to 11i.
If the application using async driver was operating on a 11.0 system without
PHKL_22126, then the group associated with that application must be modified to
include the MLOCK privilege when migrating to HP-UX 11i.