Tuning Format of Tunable Parameters Descriptions

This section describes the format for tuning Oracle Solaris parameters.

Parameter

The exact name of the tunable.

Some parameters use the naming convention module:parameter to indicate that the parameter belongs to a loadable module. For example, tmpfs:tmpfs_maxkmem means that tmpfs_maxkmem is a parameter of the tmpfs module.

Description

Briefly describes what the parameter does or controls.

Data Type

Indicates the signed or unsigned short integer or long integer. A long integer is twice the width in bits as an integer. For example, an unsigned integer = 32 bits, an unsigned long integer = 64 bits.

Units

(Optional) Describes the unit type.

Default

Indicates the value that the system uses by default.

Range

Specifies the possible range allowed by system validation or the bounds of the data type.

  • MAXINT – A shorthand description for the maximum value of a signed integer (2,147,483,647)

  • MAXUINT – A shorthand description for the maximum value of an unsigned integer (4,294,967,295)

Dynamic?

Indicates whether the parameter can by configured on a running system with the mdb or kmdb debugger (Yes), or only during boot time initialization (No).

Validation

Checks that the system applies to the value of the variable either as specified in the /etc/system file or the default value, as well as when the validation is applied.

Implicit

(Optional) Provides unstated constraints that might exist on the parameter, especially in relation to other parameters.

When to Change

Explains why someone might want to change this value. Includes error messages or return codes.

Zone Configuration

Identifies whether the parameter can be set in a exclusive-IP zone or must be set in the global zone. None of the parameters can be set in shared-IP zones.

Commitment Level

Identifies the stability of the interface. Many of the parameters in this manual are still evolving and are classified as unstable. For more information, see the attributes(7) man page.