DB2 10.5 for Linux, UNIX, and Windows

dlchktime - Time interval for checking deadlock configuration parameter

This parameter defines the frequency at which the database manager checks for deadlocks among all the applications connected to a database.

Configuration type: Database
Parameter type: Configurable online
Propagation class: Immediate
Default [range]: 10 000 (10 seconds) [1 000 - 600 000]
Unit of measure: Milliseconds

A deadlock occurs when two or more applications connected to the same database wait indefinitely for a resource. The waiting is never resolved because each application is holding a resource that the other needs to continue.

Note:

In a partitioned database environment, this parameter applies to the catalog node only.
In a partitioned database environment, a deadlock is not flagged until after the second iteration.

Recommendation: Increasing this parameter decreases the frequency of checking for deadlocks, thereby increasing the time that application programs must wait for the deadlock to be resolved.

Decreasing this parameter increases the frequency of checking for deadlocks, thereby decreasing the time that application programs must wait for the deadlock to be resolved but increasing the time that the database manager takes to check for deadlocks. If the deadlock interval is too small, it can decrease runtime performance, because the database manager is frequently performing deadlock detection. If this parameter is set lower to improve concurrency, you should ensure that maxlocks and locklist are set appropriately to avoid unnecessary lock escalation, which can result in more lock contention and as a result, more deadlock situations.