aiomemlock(F)                   19 June 1992                   aiomemlock(F)


 Name

    aiomemlock - AIO memory lock permissions file

 Description

    The Asynchronous I/O (AIO) facility allows a system administrator to
    specify certain privileged users who are allowed to lock a piece of phy-
    sical memory for AIO usage.  The /usr/lib/aiomemlock file is read by the
    aiolkinit(ADM) utility to set up the AIO locking permissions.

    aiomemlock file entries have the following format:

       user name       total lockable memory

    The following entry allows user Lucinda to lock slightly less than 4
    megabytes of memory. This is the maximum total shared among all processes
    running with the UID of ``lucinda.''

       lucinda     4000000

    A memory amount of 0 disables any locking for that user. If there is more
    than one entry for the same user, the second entry overrides the first.

    Comment lines have a number sign (#) as the first character.

 Notes

    The super user can lock memory whether or not root has entry in the
    aiomemlock file.

    Memory locked by a user is removed from the general free memory pool.
    Allowing locks should be done with care; for example, locking four mega-
    bytes on an eight megabyte system would severely degade multiuser perfor-
    mance.

 File

    /usr/lib/aiomemlock

 See also

    aio(M), aioinfo(ADM), aiolkinit(ADM)