17.10 - DeadLockTimeout - Advanced SQL Engine - Teradata Database

Teradata Vantage™ - Database Utilities

Product
Advanced SQL Engine
Teradata Database
Release Number
17.10
Release Date
July 2021
Content Type
Configuration
Publication ID
B035-1102-171K
Language
English (United States)

Determines the interval (in seconds) between deadlock timeout detection cycles. The value in DeadLockTimeout specifies the time-out value for requests that are locking each other out on different AMPs. When the system detects a deadlock, it aborts one of the jobs.

Proxy locks reduce deadlock situations for all-AMP requests that require write or exclusive locks. However, deadlocks still may be an issue on large systems with heavy concurrent usage. In batch operations, concurrent requests may contend for locks on Data Dictionary tables.

Field Group

General

Valid Range

10 though 3600 seconds

Default

240 seconds

Changes Take Effect

After the next database restart.

Recommendation

Reduce the value in this field to cause more frequent retries with less time in a deadlock state. Faster CPUs reduce the system overhead for performing deadlock checks, so you can set the value much lower than the current default of 240 seconds.

IF your applications… THEN you should…
incur some dictionary deadlocks set the value to between 30 and 45 seconds.
incur few dictionary deadlocks retain the default value of 240 seconds.
incur many true deadlocks set the value as low as 10 seconds.
are mostly online transaction processing (tactical) applications set the value as low as 10 seconds.

Related Information

For more information on locks and deadlocks, see Teradata Vantage™ - SQL Request and Transaction Processing, B035-1142 and Teradata Vantage™ - Database Administration, B035-1093.