Dynamic Multi-Pathing has multiple tunable parameters and attributes that you can configure for optimal performance. DMP provides a template method to update several tunable parameters and attributes with a single operation. The template represents a full or partial DMP configuration, showing the values of the parameters and attributes of the host.
To view and work with the tunable parameters, you can dump the configuration values of the DMP tunable parameters to a file. Edit the parameters and attributes, if required. Then, load the template file to a host to update all of the values in a single operation.
You can load the configuration file to the same host, or to another similar host. The template method is useful for the following scenarios:
Configure multiple similar hosts with the optimal performance tuning values.
Configure one host for optimal performance. After you have configured the host, dump the tunable parameters and attributes to a template file. You can then load the template file to another host with similar requirements. Veritas recommends that the hosts that use the same configuration template have the same operating system and similar I/O requirements.
Define multiple specialized templates to handle different I/O load requirements.
When the load changes on a host, you can load a different template for the best performance. This strategy is appropriate for predictable, temporary changes in the I/O load. As the system administrator, after you define the system's I/O load behavior, you can customize tuning templates for particular loads. You can then automate the tuning, since there is a single load command that you can use in scripts or cron jobs.
At any time, you can reset the configuration, which reverts the values of the tunable parameters and attributes to the DMP default values.
You can manage the DMP configuration file with the vxdmpadm config commands.
See the vxdmpadm(1m) man page.