Blog

Blog
The best minds from Teradata, our partners, and customers blog about whatever takes their fancy.
1437 Views
3 Comments

Teradata Database workload management offers a new feature starting in Teradata Database 15.10 for managing the throttle delay queue. It’s called “Prioritized Delay Queue”. This posting looks at how the Prioritized Delay Queue feature works and some things to keep in mind if you begin to use it.  The intent of this enhancement is to ensure that higher priority work is able to be released from the delay queue ahead of lower priority work.

Read more...

942 Views
0 Comments

The ResUsageSAWT logs detailed information about AMP worker tasks (AWTs). Because AWTs are a finite resource, most sites keep on eye when they are close to running out.

 

ResUsageSAWT reports in-use and max AWT counts for all of the 16 message work types on each AMP and reports them at the end of each logging interval. It also includes a column InuseMax that reflects the maximum number of AWTs in combination that were in use at any one time during the log period.  This posting is intended to clear up any confusion over what InuseMax offers, when it’s useful, and when other AWT metrics are more suitable.

 

 

Read more...

1002 Views
2 Comments

An enhancement to the Teradata optimizer in Teradata Database 16.0 will improve the performance of some queries that use a view or a derived table that contains a UNION ALL between multiple branches.

Read more...

4257 Views
0 Comments

A new feature in Teradata Database 15.0 gives the optimizer the choice to bypass all-AMP row redistributions under certain circumstances. This can be a good thing for queries that are redistributing just a few rows and the system has many AMPs. Without this feature all row redistributions, no matter of what size, would require that an AMP worker task be spawned and started up on each AMP in preparation for receiving rows.

Read more...

6527 Views
1 Comment

If you are someone who uses Database Query Log (DBQL) to keep on top of how much resource your users and applications are consuming, you are probably aware that there are different DBQL tables that collect information related to usage. Starting in Teradata Database 15.0, if you are tracking usage for utilities, that detail is carried in two places:  The DBQLogTbl and the DBQLUtilityTbl.

 

Which should you use?   Should you combine usage from both tables?  Or only consider the usage in one of the two tables?

Read more...

4760 Views
0 Comments

Teradata Workload Management comes in two versions: Teradata Integrated Workload Management (TIWM) which includes basic functionality, and Teradata Active System Management (TASM) which has a richer set of capabilities.  Both TIWM and TASM come with several system-defined workloads. This blog explains what these workloads are, why they are there, and whether you can ignore them or not.

Read more...

4472 Views
0 Comments

AMP worker tasks (AWT) are a critical resource in the Teradata Database.   In previous blog postings I’ve explained how the load and export utilities, as well as ARC backup and restore, use AMP worker tasks.  In this posting we’ll consider the replacement for ARC, Data Stream Architecture (DSA), and its use of AWTs.

 

 

Read more...

4606 Views
0 Comments

This is an update to an earlier posting in which data dictionary statistics recommendations in Teradata Database 14.0 were shared. This posting makes similar recommendations for data dictionary statistics from the 15.10 perspective.

Read more...

15878 Views
4 Comments

Both system-level and workload-level throttles can manage the concurrency of load utility jobs in the Teradata Database.   However, the point at which they release their respective throttle slots differs.  This article explains that difference.

Read more...

2966 Views
0 Comments

This posting discusses an unanticipated behavior within TASM/TIWM when it comes to selecting the workload to do the parsing engine (PE) execution activities.  

Read more...

Bloggers
Top Kudoed Authors
User Kudos Count
1
Top Kudoed Posts