Class Assignment

Unclassified Processes

A process that is already in existence at the time that WLM is initialized is not classified. Processes that have called the plock() system call are unclassified. The wait process is always an unclassified process. Unclassified processes are not assigned to the default class, but to no class at all. Unclassified processes cannot have resource limits applied to them.

Automatically Classifying Processes

Processes can be automatically classified by several criteria. Each of these criteria are specified with a list and a set of values for each class. If no list is specified, no process will match that criterion for that class.

When a process is classified, it will be checked against each class assignment rule in the /etc/wlm/rules file so that the rules are listed in the file.

A logical NOT can be performed by prefacing a property value with an exclamation point (!). Thus, "all users except X that are also not in group Y" can be specified by a single rule.

The classification choices are as follows:

user:

This lists the user names as specified in the /etc/passwd file. The names are translated to numeric user IDs at the time the WLM parameter files are loaded and the numeric user IDs are used for all classifications. The real (not effective) user ID of a process is used to match against this list.

group:

This lists the group names as specified in the /etc/group file. The names are translated to numeric group IDs at the time the WLM parameter files are loaded and the numeric group IDs are used for all classifications. The real (not effective) group ID of a process is used to match against this list.

application:

This is the pathname of the executable processes to be included in the class. The application names are either full pathnames or Korn shell patterns that match pathnames. Basenames are not allowed, therefore application path names must start with a "/". The matching is done by actual file executed. If the actual executable file is the same as the file that is derived by following the specified pathname (including symbolic links), then the process is included in the class. The application file needs to exist at the time that a class rule is loaded into the workload management system. Any changes to the application file after the class assignment rule is loaded may not result in a match.

Patterns can be specified to match a set of full pathnames using full Korn shell pattern matching syntax.

The total number of automatic classification rules that can be specified is limited to 255.

Class Assignment File Format

The files are stored in a subdirectory of /etc/wlm that you create. For example, you can create a subdirectory named sample_config. Format the class assignment rules file /etc/wlm/sample_config/rules as a table, with each line representing one class assignment rule. The first column is the name of the class to which a process matching all of the attributes in subsequent columns are assigned. The columns are separated by any number of spaces or tabs.

An attribute condition consists of a value or list of values separated by commas (and no spaces).

• If the attribute for a process matches one of the values in the list, then the attribute condition is satisfied.
• If the attribute value for a process matches one of the values in the list that is preceded by an exclamation point (!), then the condition fails.
• The special attribute condition, a single hyphen (-), is always satisfied.

The second column in the file is reserved for future extensions. The only legal value for this reserved attribute is a single hyphen (-).

The order of attributes in the file is class name, reserved, user, group and application.

Comments are lines preceded by an asterisk. The default shipped class assignment file contains comments on the first two lines that contain column headings and dividing lines to indicate which columns correspond to which attributes.

Example /etc/wlm/sample_config/rules File

* class		reserved	user    	group		application
*______		________	____		_____		___________

System		-		root		-		-
student		-		-		student		!/bin/ksh,!/bin/bsh,!/bin/csh
Default		-		-		-		-