aio_init(3) — Linux manual page

NAME | LIBRARY | SYNOPSIS | DESCRIPTION | STANDARDS | HISTORY | SEE ALSO | COLOPHON

aio_init(3)             Library Functions Manual             aio_init(3)

NAME         top

       aio_init - asynchronous I/O initialization

LIBRARY         top

       Real-time library (librt, -lrt)

SYNOPSIS         top

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

       void aio_init(const struct aioinit *init);

DESCRIPTION         top

       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         top

       GNU.

HISTORY         top

       glibc 2.1.

SEE ALSO         top

       aio(7)

COLOPHON         top

       This page is part of the man-pages (Linux kernel and C library
       user-space interface documentation) project.  Information about
       the project can be found at 
       ⟨https://www.kernel.org/doc/man-pages/⟩.  If you have a bug report
       for this manual page, see
       ⟨https://git.kernel.org/pub/scm/docs/man-pages/man-pages.git/tree/CONTRIBUTING⟩.
       This page was obtained from the tarball man-pages-6.9.1.tar.gz
       fetched from
       ⟨https://mirrors.edge.kernel.org/pub/linux/docs/man-pages/⟩ on
       2024-06-26.  If you discover any rendering problems in this HTML
       version of the page, or you believe there is a better or more up-
       to-date source for the page, or you have corrections or
       improvements to the information in this COLOPHON (which is not
       part of the original manual page), send a mail to
       [email protected]

Linux man-pages 6.9.1          2024-05-02                    aio_init(3)

Pages that refer to this page: aio(7)