16.10 - Utility Protocols - Teradata Workload Management

Teradata Database Workload Management User Guide

Teradata Workload Management
June 2017
User Guide
Utilities use sessions differently. In general, a utility logs on the following types of sessions:
Control SQL Session
A session that executes SQL requests related to utility work. Almost all Teradata utilities have a control SQL session.
Auxiliary SQL Session
An optional, second SQL session maintains a restart log for recovery.
Utility Sessions
One or more sessions are used for sending and receiving data to and from Teradata Database.
The following table describes whether a utility uses these sessions.
Utility Names Control SQL Session Auxiliary SQL Session Utility Sessions
FastLoad, MultiLoad, FastExport Yes Yes Yes
Teradata Parallel Transporter Load, Update, and Export operators Yes Yes Yes
MLOADX Yes Yes Yes (using SQL sessions)
JDBC FastLoad, JDBC FastExport Yes No Yes
CSP Save Dump Yes No Yes
Archive/Recovery utility Yes No Yes
DSA Yes No No
Utility sessions are subject to different throttles than SQL sessions. The SQL sessions and requests issued through them are subject to these throttles:
  • Query session
  • Workload
  • System

Utility sessions are subject only to utility session rules.

TASM and Teradata utilities treat the whole load/unload process as one Unit of Work. A Unit of Work starts with the BEGIN LOADING/MLOAD/EXPORT request on the control SQL session. It ends with the END LOADING/MLOAD/EXPORT request. This means that a utility Unit of Work spans multiple SQL requests. Only the first SQL request of a unit on the control SQL session satisfies the utility classification criterion and is assigned to a utility workload. Subsequent requests are assigned to the same utility workload. SQL requests outside the load/unload unit and SQL requests from the auxiliary SQL session can be assigned to different workloads. All applicable throttle counters are checked and incremented only at the beginning of a unit and decremented only at the end of the unit. For backup and restore, the entire script is treated as one unit.