nstrpty(5) [hpux man page]

nstrpty(5)							File Formats Manual							nstrpty(5)

NAME

       nstrpty - maximum number of STREAMS-based pseudo terminals (pts)

VALUES

   Default
   Allowed Values
DESCRIPTION

       is  the number of STREAMS-based pseudo terminal (pts) drivers that a system can support.  The pty driver provides support for a device-pair
       called a pseudo terminal.  A pseudo terminal is a pair of character devices, a master device, and a slave device.  These  allow	communica-
       tion between an application process and a server process.  When sending data to pty devices (such as  windows), a pty device must exist for
       every window that is open at any given time.

       should  be set to a value that is equal to, or greater than, the number of pty devices on the system that will be using	STREAMS-based  I/O
       pipes.	Using a parameter value significantly larger than the number of ptys is not recommended.  is used when creating data structures in
       the kernel to support STREAMS-based ptys, and an excessively large value wastes kernel memory space.

   Who Is Expected to Change This Tunable?
       Users with the privilege.  See privileges(5) for more information about privileged access on systems that support fine-grained privileges.

   Restrictions on Changing
       Changes to this tunable take effect at the next reboot.

   When Should the Value of This Tunable Be Raised?
       This tunable value needs to be raised when the system runs out of ptys.

   What Are the Side Effects of Raising the Value?
       More system memory is used.

   When Should the Value of This Tunable Be Lowered?
       This value should be lowered when a minimal system is being created.

   What Are the Side Effects of Lowering the Value?
       The system may run out of ptys.

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), privileges(5), pts(7).

							     Tunable Kernel Parameters							nstrpty(5)

NSTREVENT(5)							File Formats Manual						      NSTREVENT(5)

NAME

       NSTREVENT - maximum number of outstanding STREAMS bufcalls

VALUES

   Failsafe
   Default
   Allowed values
   Recommended values
DESCRIPTION

       This tunable limits the maximum number of outstanding that are allowed to exist in the system at any given time.

       This  tunable is intended to protect the system against resource overload caused by the combination of modules running in all streams issu-
       ing an excessive number of The value selected should be equal to or greater than the combined maximum number  of  that  can  be	reasonably
       expected during normal operation from all streams on the system.  are used by STREAMS modules in low memory situations.

   Who Is Expected to Change This Tunable?
       Any customer.

   Restrictions on Changing
       Changes to this tunable take effect at next reboot.

   When Should the Value of This Tunable Be Raised?
       When the system has a lot of low memory situations.

   What Are the Side Effects of Raising the Value of This Tunable?
       If  too	big  a	number	is  chosen,  the STREAMS subsystem preallocates more memory for internal data structures than may be needed.  This
       reduces the amount of  memory available to applications and the system.

   When Should the Value of This Tunable Be Lowered?
       If the tunable is increased for a particular STREAMS module/driver, this tunable can be lowered when that STREAMS module/driver is removed.
       It should be returned to its previous value.  However, HP does not recommend a value lower than the default value.

   What Are the Side Effects of Lowering the Value of This Tunable?
       During low memory situations, it will bring down system performance.

   What Other Tunable Should Be Changed at the Same Time as This One?
       None.

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.

							     Tunable Kernel Parameters						      NSTREVENT(5)