SunSolve Internal

Infodoc ID		Synopsis		Date
6331		Verifying tunable parameters set in /etc/system		14 Mar 2000

Description

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Many times it is desirable to check the parameters set in the /etc/system
file after rebooting a machine. While this is not really necessary,
as errant entries cause a diagnostic message during boot, some people
feel better being able to look at the values.


As root, execute the following;

	adb -k /dev/ksyms /dev/mem

Adb will reply with the amount of physical memory in hex pages
with a line similar to "physmem xxxx."  On the sun4u architecture, a page
is 8K.  On all other architectures, a page is 4K.

A prompt will not be received after this, but adb is running. To check 
a tunable parameter, enter one of the following:

parameter/D	(displays the integer parameter in decimal)

   or

parameter/X	(displays the integer parameter in hexadecimal)

(Various other display formats are available. See the adb man page.)

Typically, the "parameter" above is replaced with the kernel symbol
being examined. For example:

maxusers/D		(will display what maxusers is set to)

shminfo_shmmax/D	(to display max shared memory segment size)


To find names of other kernel variables, look in the system header files
located in /usr/include/sys. These are particularly helpful in determining
the variable type (int, short, signed, unsigned) in order to use the
correct output format in adb.

Also note that by substituting ? for / in the above commands, the user can see
the compiled-in values (usually defaults) in the kernel.

Exit adb by typing $q (return).

NOTE: The information above in this document is correct for Solaris 2.6 and
older releases.  For Solaris 7 and later, it is correct only if the system is
booted in 32-bit mode.  If the system is sun4u (Ultra architecture), and the
results of the isainfo -n command are "sparcv9", then the system is booted in
64-bit mode.  Most kernel variables which are 4 bytes long in the 32-bit
kernel are 8 bytes long in the 64-bit kernel, and will not display correct
values when the commands above are used.  Substitute the appropriate adb
modifier.  Instead of D, use E.  Instead of X, use J.  See the adb man page
for details on the format modifiers.