WLM offers a fine level of control over resource allocation. However, it is easy to set up conflicting values for the various parameters and obtain undesirable system behaviors. The following tips can help you avoid creating conflicts:
Know your user base and their basic computing needs when defining classes and class assignment rules.
Know the resource needs of the main applications.
Prefer targets over minimum and maximum limits. Targets give the system greater flexibility than hard limits, and targets can help prevent starving applications.
Try to balance the load using only targets and monitor the system with the wlmstat command. Apply minimum limits for classes that do not receive sufficient share.
Prioritize some jobs by using tiers.
Use maximum only as a last resort to restrain applications that consume large quantities of share. Maximum can also be used to place hard limits on users' resource consumption (for example, for accounting purposes).
You can specify the properties for the WLM subsystem by using either a Web-based System Manager graphical user interface, SMIT, an ASCII-oriented user interface, or by creating flat ASCII files. The Web-based System Manager and SMIT interfaces record the information in the same flat ASCII files. These files are called the WLM property files and are named classes, description, rules, limits, and shares. The WLM property files can only be loaded by the root user.
You can define multiple sets of property files, defining different configurations of workload management. These configurations are usually located in subdirectories of /etc/wlm. A symbolic link /etc/wlm/current points to the directory containing the current configuration files. This link is updated by the wlmcntrl command when WLM starts with a specified set of configuration files.