aio_listio_max.5 (2010 09)

aio_listio_max(5) aio_listio_max(5)

(Tunable Kernel Parameters)

NAME

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

listio() call

VALUES

Failsafe

256

Default

256

Allowed values

The minimum value allowed is 2. The maximum value allowed is

0x100000. The value is further con-

strained in that it must be less than or equal to

aio_max_ops.

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

listio() 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

aio_listio_max

must be less than or equal to aio_max_ops.

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 parame-

ter values. After installation, some tunable parameters may no longer be at the default or recommended

values. For information about the effects of installation on tunable values, consult the documentation for

the kernel software being installed. For information about optional kernel software that was factory

installed on your system, see HP-UX Release Notes at

http://www.hp.com/go/hpux-core-docs

AUTHOR

aio_listio_max was developed by HP.

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aio_listio_max(5) aio_listio_max(5) (Tunable Kernel Parameters) NAME aio_listio_max - the maximum number of POSIX asynchronous I/O operations that can be specified in a listio() call VALUES Failsafe 256 Default 256 A Allowed values The minimum value allowed is 2. The maximum value allowed is 0x100000. The value is further constrained in that it must be less than or equal to aio_max_ops. Specify a positive integer value.
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(Notes) A (Notes) aA 2 Hewlett-Packard Company −1− HP-UX 11i Version 3: September 2010