Files Reference

Workload Manager classes File

Purpose

Contains the definition of Workload Manager (WLM) superclasses or subclasses for a given configuration.

The classes file in the /etc/wlm/Config directory describes the superclasses of the WLM configuration, Config. If the superclass Super of this configuration has subclasses defined, these subclasses are defined in the file /etc/wlm/Config/Super/classes.

Some attributes apply to only superclasses or to only subclasses. The description of the classes file uses the terms class or classes when a statement applies to both superclasses and subclasses.

The classes file is organized into stanzas. Each stanza names a WLM class and contains attribute-value pairs that describe characteristics of the class.

Attributes

Each stanza names a WLM class. Class names can contain only upper- and lowercase letters, numbers, and underscores. They are limited to 16 characters in length. The only names that have special meaning to the system are Default, Shared, Unclassified, Unmanaged, and System. You cannot use Unclassified and Unmanaged as class names. The superclasses Default, Shared, and System are always defined. The subclasses Default and Shared are always defined.

The following attributes are defined in the classes file:

tier	Specifies the position of the class in the hierarchy of resource limitation desirability for all classes. A class with a lower tier value will be more favored than a class with a higher tier value. The tier value is a number from 0 to 9. If this attribute is not defined, it defaults to 0.
inheritance	If the inheritance attribute is given the value Yes, the children of processes in this class remain in the class upon execution, regardless of the automatic assignment rules in effect. If this attribute is given No, the normal assignment rules apply. If not defined, the attribute defaults to No.
localshm	Indicates whether memory segments accessed by processes in different classes remain local to the class they were initially assigned to or if they go to the Shared class. The possible value is Yes or No. If not specified, the default is No.
authuser	Specifies the user name of the user allowed to assign processes to this class. If not defined, this attribute defaults to the empty string ("").
authgroup	Specifies the group name of the group of users allowed to assign processes to this class. If not defined, the attribute defaults to the empty string.
rset	Names the resource set to which the processes in the class have access. If the attribute is not defined, it defaults to an empty string, meaning that the class has access to all the resources on the system.
adminuser	Specifies the user name of the user allowed to administer the subclasses of this superclass. If not defined, the attribute defaults to the empty string. This attribute is valid only for superclasses.
admingroup	Specifies the group name of the group of users allowed to administer the subclasses of this superclass. If not defined, the attribute defaults to the empty string. This attribute is valid only for superclasses.

The attributes that have not been explicitly set by a WLM administrator using any of the administration tools (file editing, command line, or SMIT) are omitted in the property files.

The default values mentioned above are the system defaults and can be modified using a special stanza named "default."

Implementation Specifics

This file is part of Base Operating System (BOS) Runtime.

Files

classes

Defines the superclasses or subclasses of a WLM configuration

Security

The WLM property files defining the superclasses of a WLM configuration must have write permission only for the root user. The WLM property files defining the subclasses of a superclass must have write permission for the adminuser and admingroup for the superclass.

If there is no adminuser for the superclass, the files should be owned by root. If no admingroup exists for a superclass, the WLM property files for the superclass should be group "system" with no write permission for group.

Example

The following entry at the beginning of the classes file modifies the default values for the tier and inheritance attributes so that if they are not defined for some (or all) of the classes specified in the file, the tier value is 1 and the inheritance value is Yes:
```
default:
   tier          = 1
   inheritance   = "yes"
```
The scope of these user-defined default values is limited to the file where they appear. For instance, if the above default stanza appears in the top-level classes file of a configuration, it does not affect the default values for the classes files defining the subclasses of the various superclasses.

The following is an example of a typical /etc/wlm/Config/classes file:

* system defined classes
* All attributes to default value
* Attribute values can be specified
*
Default:
System:
Shared:
* User defined classes
*
Super1:
    inheritance   = "yes"
    adminuser     = "bob"
    authgroup     = "devlt"
Super2:
    tier          = 4
    localshm      = "yes"
    admingroup    = "sales"
    authuser      = "sally"
    rset          = "part1"

Note: The asterisk (*) is a comment character. Comments are added by directly editing the file. However, when you use the command line, or SMIT to create, modify, or delete classes, the comments are removed.

Related Information

The lsclass command, mkclass command, chclass, rmclass command.

The shares file, limits file, rules file.

Chapter 13. Workload Manager in AIX 5L Version 5.1 System Management Concepts: Operating System and Devices