Tuning kernel parameters

Despite the fact that most kernel configuration parameters are automatically set during installation, you may need to adapt certain parameters to the needs of your site. This section provides recommendations for configuring these parameters.




	NOTE: Use SAM to verify (or adapt) kernel parameters.

nproc

Specifies the maximum total number of processes that can exist simultaneously in your system.

Range:: 10 to memory limited
Default value:: (20 + 8 * MAXUSERS)

If your application uses one process per X.25 connection, we recommend that you add MAXXDEVS to your current value to make the nproc parameter dependent on it.




	CAUTION: To avoid kernel regeneration problems, make sure you enclose the entire formula with brackets. Example: the new formula for `nproc` should be `(20 (8 * MAXUSERS) + MAXXDEVS)`.

maxuprc

Specifies the maximum number of simultaneous processes for each user (other than superuser).

Range:: 3 to nproc -4
Default value:: 25




	CAUTION: Same recommendation that applies to `nproc` (unless the application is run by superuser).

nfile

Specifies the maximum number of open files allowed on the system at any one time.

Range:

14 to memory-limited

Default value:

( (16 x (NPROC + 16 + MAXUSERS) / 10) + 32 + 
(2 x NPTY) )

If you have an application that uses programmatic access over X.25 to open a socket descriptor (file descriptor) for each connection we recommend that you add MAXXDEVS to your current value unless nproc already depends on MAXXDEVS. In this case leave nfile unchanged.

ninode

Specifies the maximum number of open inodes allowed in the core.

Range:: 14 to memory-limited
Default value:: ( (NPROC + 16 + MAXUSERS) + 32)

Same recommendation that applies to nfile unless nproc already depends upon MAXXDEVS in which case inode can be left as it is.

maxfiles

Specifies the maximum number of files a process can have open.

Range:: 30 to 2038
Default value:: 60

Same recommendation that applies to nproc.

max_ixaddrs

Maximum number of remote IP addresses over X.25.

Range:: 10 to system limit
Default value:: 100

Set this value to the numbers of remote sites (IP addresses) you need to reach through TCP/IP over X.25.




	NOTE: Once these Kernel Parameters have been modified, SAM will re-generate a new kernel and reboot the system.