HP-UX Reference (11i v2 04/09) - 5 Miscellaneous Topics (vol 9)

maxssiz(5) maxssiz(5)

(Tunable Kernel Parameters)

lower maxssiz_64bit

to its previous value. This will allow the speciﬁc application to beneﬁt from the

increased stack size but will not cause additional stack growth for applications which do not need it.

When Should the Value of This Tunable Be Lowered?

This tunable should be lowered if swap space is at a premium on the system, and several poorly written

programs, or malicious programs, are using swap space to the detriment of more critical user processes.

For example, several students at a university might execute less than production level code and leak

memory all over the place.

What Are the Side Effects of Lowering the Value?

Lowering this tunable will limit the amount of memory available for stack usage per process. This could

cause processes with large stack requirements to terminate with a [SIGSEGV] error.

What Other Tunable Values Should Be Changed at the Same Time?

maxdsiz should be considered because it performs a similar function of limiting swap usage by process

data segment.

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://docs.hp.com

AUTHOR

maxssiz was developed by HP.