Can You Limit Number of Sessions Per User ?

Database
Enthusiast

Can You Limit Number of Sessions Per User ?

Not sure if this is the correct place in the forum for this question but here goes ...

We have a problem with a web based application written by another department which accesses our warehouse via OLEDB and is flooding our system with queries.

This application sends a query to the system and if it doesn't get a response within x seconds sends it again, leaving the original query still active and keeps doing this until it gets a response. Normally this isn't a problem as it gets it's response within the allowed timescale, but when our system is very busy (which it is quite often these days) it very quickly grabs all of the available sessions and blocks any other user running a query.

As we are struggling to get the department responsible for the rogue application to amend it, is there a way by which we can limit the number of sessions that any one User Id can have active at a time ?

We're running V2R5.1.

Thanks

Alistair
4 REPLIES
Teradata Employee

Re: Can You Limit Number of Sessions Per User ?

Have you investigated using priority scheduler? This allows you to place a ceiling on the amount of resources an application can have. Suggest you carefully read the "Teradata Performance Optimization" manual for V2R5.1 - specifically the chapter on priority schedulre. This document is available for download from Teradata.com.

Another option is to use ODBC connection pooling. More information is available in the Teradata ODBC manual also available for downloaed from the Teradata website.

Teradata Employee

Re: Can You Limit Number of Sessions Per User ?

Also in v2r5 there was Teradata DQM Administrator (which in v2r6 was renamed the Teradata DWM. DQM will allow you to limit the limit the number of logons and the number of running queries for specific users or accounts.
Enthusiast

Re: Can You Limit Number of Sessions Per User ?

Jeff,

Thanks for the replies, we're in the process of upgrading to V12 and will be introducing Priority Scheduler and DWM at that point.

We are trying to get the department that are in charge of the application to use connection pooling but are struggling to get them to do it, hence why we are looking for a way of doing it at the Teradata end.

I was just hopeful that there was a simple way to limit a user with what we currently have, but it looks like we haven't.
Enthusiast

Re: Can You Limit Number of Sessions Per User ?

Hi,

I am using TD 12. An application is firing 60 concurrent queries. Our SLA is 10 seconds for a query but its taking 20 secs to execute a query. If we increase the number of sessions for a query can we achieve the SLA? Please advise.

Thanks in advance.