As a safeguard against expediting workloads that are not really tactical, the migration process yields a pre-configured exception for each tactical workload. These exceptions cannot be disabled, but the associated values can be changed after upgrade to SLES 11.
The exception specifies default threshold values, as shown in the following table.
| Exception Criterion | Default Threshold Value |
|---|---|
| CPU per node | 2 CPU seconds |
| I/O per node | 200 MB |
| CPU (sum over all nodes) | 2 CPU seconds * number of nodes |
| I/O (sum over all nodes) | 200 MB * number of nodes |
If a tactical workload exceeds any of the defined thresholds, it is diverted to the WD-Default workload in the Timeshare tier. This default workload is assigned an access level of Medium.
You cannot disable tactical workload exceptions, but you can use the Workload Designer portlet in Teradata Viewpoint to change the default values and the workload to which queries divert.
The workload to which tactical queries divert must be in the Timeshare tier or, if available and appropriate, an SLG tier.