plucky (3) aio_init.3.gz

Provided by: manpages-dev_6.9.1-1_all bug

NAME

       aio_init - asynchronous I/O initialization

LIBRARY

       Real-time library (librt, -lrt)

SYNOPSIS

       #define _GNU_SOURCE         /* See feature_test_macros(7) */
       #include <aio.h>

       void aio_init(const struct aioinit *init);

DESCRIPTION

       The  GNU-specific  aio_init()  function  allows the caller to provide tuning hints to the glibc POSIX AIO
       implementation.  Use of this function is optional,  but  to  be  effective,  it  must  be  called  before
       employing any other functions in the POSIX AIO API.

       The  tuning  information  is  provided  in  the buffer pointed to by the argument init.  This buffer is a
       structure of the following form:

           struct aioinit {
               int aio_threads;    /* Maximum number of threads */
               int aio_num;        /* Number of expected simultaneous
                                      requests */
               int aio_locks;      /* Not used */
               int aio_usedba;     /* Not used */
               int aio_debug;      /* Not used */
               int aio_numusers;   /* Not used */
               int aio_idle_time;  /* Number of seconds before idle thread
                                      terminates (since glibc 2.2) */
               int aio_reserved;
           };

       The following fields are used in the aioinit structure:

       aio_threads
              This field specifies the maximum number of worker threads that may be used by the  implementation.
              If  the  number  of  outstanding I/O operations exceeds this limit, then excess operations will be
              queued until a worker thread becomes free.  If this field is specified with a value less  than  1,
              the value 1 is used.  The default value is 20.

       aio_num
              This  field should specify the maximum number of simultaneous I/O requests that the caller expects
              to enqueue.  If a value less than 32 is specified for this field, it is rounded  up  to  32.   The
              default value is 64.

       aio_idle_time
              This  field  specifies  the amount of time in seconds that a worker thread should wait for further
              requests before terminating, after having completed a previous request.  The default value is 1.

STANDARDS

       GNU.

HISTORY

       glibc 2.1.

SEE ALSO

       aio(7)