aio(F)                          19 June 1992                          aio(F)


 Name

    aio - AIO tunable parameters

 Description

    The Asynchronous I/O (AIO) facility is an installable package typically
    used by special purpose applications, such as database servers. There are
    a set of parameters in the mtune file associated with AIO; if necessary
    (for example, console messages indicate running out of AIO resources),
    these can be altered by using idtune(ADM).  The major tunable parameters
    are as follows:

    NAIOPROC       the number of processes which may be simultaneously doing
                   AIO. The default value is 5.

    NAIOREQ        the maximum number of pending AIO requests. The default
                   value is 120.

    NAIOREQPP      The maximum number of AIO requests that a single process
                   can have pending. The default value is 120, meaning that
                   one process can potentially exhaust all AIO resources.

    The AIO tunable parameters that follow are unlikely to need changing, but
    are documented here for completeness:

    NAIOBUF        The number of AIO buffers. In the current implementation,
                   this should always be set to the same value as NAIOREQ.

    NAIOHBUF       The number of AIO hash queues (internal).

    NAIOLOCKTBL    number of entries in the internal kernel table for AIO
                   lock permissions. The default value is 10. If there are
                   many entries in the /usr/lib/aiomemlock file, this number
                   might need to be increased.

 File

    /usr/lib/aiomemlock

 See also

    aio(M), aiolkinit(ADM), aiomemlock(F), idtune(ADM), mtune(F), stune(F)