AIX 5L Problem Determination - IBM Redbooks

This manual assignment can be done either by a WLM command, which
could be invoked directly or through SMIT or Web-based System Manager, or
by an application, using a function of the WLM Application Programming
Interface. Manual assignment overrides automatic assignment.
10.5.2 Automatic assignment
The automatic assignment of processes to classes uses a set of class
assignment rules specified by a WLM administrator. There are two levels of
assignment rules:
► A set of assignment rules at the WLM configuration level used to determine
which superclass a given process should be assigned to.
► A set of assignment rules at the superclass level used to determine which
subclass of the superclass the process should be assigned to.
The assignment rules at both levels have exactly the same format.
When a process is created by fork, it remains in the same class as its parent.
Usually, reclassification happens when the new process calls the system call
exec. In order to classify the process, WLM starts by examining the top level
rules list for the active configuration to find out which superclass the process
should belong to. For this purpose, WLM takes the rules one at a time, in the
order they appear in the file, and checks the current values for the process
attributes against the values and lists of values specified in the rule. When a
match is found, the process will be assigned to the superclass named in the first
field of the rule. Then the rules list for the superclass is examined in the same
way to determine which subclass of the superclass the process should be
assigned to. For a process to match one of the rules, each of its attributes must
match the corresponding field in the rule. The rules to determine whether the
value of a process attribute matches the values in the field of the rules list are as
follows:
► If the field in the rule has a value of hyphen (-), any value of the corresponding
process attribute is a match.
► If the value of the process attribute (for all the attributes except type) matches
one of the values in the list in a rule, and it is not excluded (prefaced by an
exclamation point (!)), it is considered a match.
► When one of the values for the type attribute in the rule is comprised of two or
more values separated by a plus sign (+), a process will be a match for this
value only if its characteristics match all the values mentioned above.
As previously mentioned, at both superclass and subclass levels, WLM goes
through the rules in the order in which they appear in the rules list, and classifies
the process in the class corresponding to the first rule for which the process is a
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