POSIX Message Queue

POSIX Message Queue - Settings

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aio_listio_max

aio_listio_max(5)						File Formats Manual						 aio_listio_max(5)

NAME

       aio_listio_max - the maximum number of POSIX asynchronous I/O operations that can be specified in a listio() call

VALUES

   Failsafe
   Default
   Allowed values
       The minimum value allowed is The maximum value allowed is The value is further constrained in that it must be less than or equal to

       Specify a positive integer value.

DESCRIPTION

       This  parameter	places	a  limit  on  the system resources that can be consumed if a large number of POSIX asynchronous I/O operations are
       requested in a single call.  The value should be set large enough to meet system programming needs  while  protecting  the  system  against
       excessive asynchronous I/O operations initiated by a malfunctioning process.

   Who Is Expected to Change This Tunable?
       System administrators that run applications requiring heavy usage of POSIX AIO to file systems.

   Restrictions on Changing
       This tunable is dynamic (tuning will take effect immediately on the running system).

   What Other Tunables Should Be Changed at the Same Time as This One?
       The value assigned to must be less than or equal to

WARNINGS

       All  HP-UX kernel tunable parameters are release specific.  This parameter may be removed or have its meaning changed in future releases of
       HP-UX.

       Installation of optional kernel software, from HP or other vendors, may cause changes to tunable  parameter  values.   After  installation,
       some  tunable  parameters may no longer be at the default or recommended values.  For information about the effects of installation on tun-
       able values, consult the documentation for the kernel software being installed.	For information about optional kernel  software  that  was
       factory installed on your system, see at

AUTHOR

       was developed by HP.

SEE ALSO

       kctune(1M), sam(1M), gettune(2), settune(2), aio(5), aio_max_ops(5).

							     Tunable Kernel Parameters						 aio_listio_max(5)

Programming