16.50 - Sessions Collector - Teradata Workload Management

Teradata® Viewpoint User Guide

Teradata Viewpoint
Teradata Workload Management
January 2021
User Guide

This topic provides additional information about the Sessions data collector that may be helpful.

Session-level statistics are collected in memory by the database at a configurable sample rate. The default option in Teradata Viewpoint collects session data at the same rate as sampled by the database. Collecting session data more frequently than the session sample rate in the database results in duplicate data collection and wasted CPU. You can set this rate in the Monitored Systems portlet by selecting Monitor Rates from the Setup list.

If you want to see a query with an interval shorter than 60 seconds on Query Monitor, change the interval value in the ruleset for the system.

The data is also used for the Active Sessions metric in the System Health, Metrics Analysis, and Metric Heatmap portlets.

If this collector is not enabled, the Queries portlets always display zero sessions. If this collector is enabled and then disabled, the Queries portlets display stale session data. The Sessions collector and the System Stats collector must be enabled for the Active Sessions metric to display data in the System Health and Metric Heatmap portlets.

The Sessions collector retains utility data for the Query Monitor utility view. The Sessions collector is required for Session alerting.

SQL and Explain data is collected by querying the Teradata Monitor partition using the PM/API. It gathers SQL, Explain and query band information from currently running sessions for requests that meet the SQL and Explain thresholds. SQL, Explain and query band information displays in the details view in the following portlets only if SQL and Explain data is collected for that time period:
  • My Queries
  • Query Groups
  • Query Monitor
  • Query Spotlight
  • Workload Monitor