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nswapdev(5) [hpux man page]

nswapdev(5)							File Formats Manual						       nswapdev(5)

NAME

       nswapdev - maximum number of devices that can be enabled for swap

VALUES

   Default
   Allowed values
DESCRIPTION

       Swap  devices  are  managed in a table for easier indexing in the kernel.  sets the kernel variable responsible for the upper limit on this
       table, and thus the upper limit to devices which can be used for swap.

   Who is Expected to Change This Tunable?
       Anyone.

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

   When Should the Value of This Tunable Be Raised?
       If another swap device is added to the system which would increase the number of devices above and returns to the caller (see the swapon(2)
       manpage).

   What Are the Side Effects of Raising the Value?
       More  devices  can be added to the system, and the kernel will need a little more memory for the table.	A small performance side effect of
       the kernel having to scan more devices to check for a duplicate device during is also true, but realistically negligible.

   When Should the Value of This Tunable Be Lowered?
       Only if you are sure the system will never go over a certain number of swap devices, and you wish to lower this tunable	to  save  a  small
       amount of kernel memory and kernel performance during operations.

   What Are the Side Effects of Lowering the Value?
       No side effects other than the primary and presumably desired new limitation on the number of swap devices.

   What Other Tunable Values Should Be Changed at the Same Time?
       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						       nswapdev(5)

Check Out this Related Man Page

npty(5) 							File Formats Manual							   npty(5)

NAME

       npty - maximum number of BSD pseudo terminals (ptys)

VALUES

   Default
   Allowed Values
DESCRIPTION

       is  the	number	of  pseudo  terminal  (pty) 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 communication 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.

       Using a parameter value significantly larger than the number of ptys is not recommended.  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), pty(7).

							     Tunable Kernel Parameters							   npty(5)
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