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AIO_INIT(3) Linux Programmer's Manual AIO_INIT(3)
aio_init - POSIX asynchronous I/O initialization
#define _GNU_SOURCE /* See feature_test_macros(7) */
#include <aio.h>
void aio_init(const struct aioinit *init);
Link with -lrt.
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.
The aio_init() function is available since glibc 2.1.
This function is a GNU extension.
aio(7)
This page is part of release 3.32 of the Linux man-pages project. A
description of the project, and information about reporting bugs, can be found
at http://www.kernel.org/doc/man-pages/.
Linux 2010-10-06 AIO_INIT(3)
HTML rendering created 2010-12-03 by Michael Kerrisk, author of The Linux Programming Interface