.TH mtune "" "" "System Administration"
.PC "Define tunable kernel variables"
.B "/etc/conf/mtune"
.PP
File
.B mtune
defines all of the tunable variables within the kernel.
.II "buffer cache, resize"
.II "virtual consoles, set"
These variables let you configure some aspects of your kernel, without
having to modify the kernel's drivers or recompile the kernel.
.PP
Command
.B idmkcoh
reads this file when it builds a new kernel, and uses its contents to
help patch the newly build kernel.
A
.B mkdev
script (kept in a subdirectory of
.BR /etc/conf )
also sets appropriate variables within this file,
based on your answers to its questions.
.PP
Each line within
.B mtune
defines one tunable parameter.
A line consists of four fields, as follows:
.IP "\fB1. \fIName\fR"
This field names the parameter.
It cannot exceed 20 characters.
.IP "\fB2. \fIMinimum Value\fR"
The legal minimum value of this parameter.
.IP "\fB3. \fIDefault Value\fR"
The default value for this parameter.
This value can be overridden by an entry in file
.BR /etc/conf/stune .
.IP "\fB4. \fIMaximum Value\fR"
The legal maximum value of this parameter.
.PP
Note that under \*(UN System V, fields 2 and 3 are reversed.
A line that begins with the pound sign `#' is a comment, and is ignored by
.B idmkcoh
when it builds a new kernel.
.PP
For details on the parameters that this file sets, read the comments within
this file.
.SH "See Also"
.Xr "Administering COHERENT," administe
.Xr "device drivers," device_dr
.Xr "mdevice," mdevice
.Xr "sdevice," sdevice
.Xr "stune" stune
.SH "Notes"
.II "kernel^tunable variables"
.II "tunable variables"
.B mtune
contains comments that describe the kernel variables that you can tune.
If you wish to tune the kernel, you should read this file and modify it
appropriately.
The variables are documented in this file rather than in the \*(CO manual
to ensure that you have exactly accurate information about the variables
that reside in the version of the kernel on your system.
