0 - 11 of 11 tags for amp worker tasks

Teradata is a message passing system.  Messages are sent from parsing engines to AMPs, and from  AMPs to AMPs, and from AMPs to parsing engines.  That’s the key way that components in a shared nothing architecture pass data and work requests among themselves.

When a message arrives on an AMP and the message represents work that needs to get done on the AMP, that message is assigned a“work type”, depending on the importance of the work-to-be-done.  There are 16 different work types supported:  Work00 to Work15.      

Under usual conditions, all load utility jobs and all queries run using AMP worker tasks (AWTs) of the same message work types:  Work00, Work01, and Work02.  However, if you increase AWTs per AMP above a certain threshold, then all your utility jobs will be assigned to different work types and given their own reserve pools.   

If you are someone who monitors or is otherwise interested in AWTs and how they are being used, this posting describes changes related to your utility jobs, and what options you have for managing these changes.

MLOADX is a new load utility enhancement introduced in Teradata Database 14.10 which is intended to overcome some of the limitations that are associated with standard MultiLoad.  This posting focuses on how workload management options will open up MLOADX for more expanded usage in Teradata Database 15.10.

If I told you there was a way you might be able to speed up parsing time for your queries, would you be interested?  

In Teradata Database 14.10.02 there is a new capability that allows you to expedite express requests, and I’d like to explain how that works, describe when it can help you, and make some suggestions about how you can use it to get the best performance you can from parsing when the system is under stress.  But first a little background.

This session gives a close-up picture of what AMP worker tasks are and how they support user work.

Most of us are aware of AMP worker tasks, and some of us are even obsessive about not running out of this finite resource.  But that’s on the AMP.  What about the tasks supporting user work on the parsing engine (PE)?  Should we be just as vigilant about what’s happening with tasks at the PE level?

Not really.  Here’s why.

I gave a presentation on AMP worker tasks at the Teradata User Group conference last week in Washington DC.   A question came from someone in the audience concerning FastExport jobs in response mode, and whether or not they were holding AMP worker tasks.  This post addresses that question.

There’s a comment on an earlier blog posting of mine from 2009 titled Controlling the Flow of Work in Teradata.  The comment poses a question that is more reasonably answered by making second posting on flow control. 

AMP worker tasks are the dedicated tasks inside each AMP that get the database work done.  As there are a limited number, this important resource is actively monitored by DBAs on busy systems.  TASM system-level events can take care of the monitoring for you, and based on a threshold you have set set, will trigger changes in workload management setup to manage the AWT shortage.  How AMP worker task events do their monitoring has changed in Teradata Database 13.10, and this posting describes those changes.

Reserving AMP worker  tasks (AWT) for tactical applications is a technique to protect business-critical, short queries, when the platform is experiencing AMP worker task exhaustion.   If you are thinking about reserving AWTs, there are two different settings for which you will be required to provide values.  This posting discusses what these two settings

When you push too much paper into your shredder, it jams; when you pour too much coffee into your cup, it overflows; when you eat too much food, you…well, you know. Everything’s got limits.

NOTE:  This content is only relevant to sites on Teradata 12 or earlier.

Congratulations, you’re on Teradata 12! Now it’s time to start redefining your AMP worker task (AWT) monitoring procedures by making use of the new ResUsageSAWT table.