What causes the log full conditions and how to manage it?

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 Long running transactions that can cause log full conditions affecting other applications include:

 1) A LOAD operation, including ADMIN_MOVE_TABLE that makes use of LOAD.

2) A CREATE INDEX operation.

3) An idle application which has not issued COMMIT or ROLLBACK after modifying the database.

 How can this be addressed?

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 Advanced Log Space Management (ALSM) helps to minimize application failures caused by log full errors (SQL0964N) as the result of a long running transaction holding back the active log space.

 This is particularly useful if such a long running transaction does not generate much transaction log data in comparison to other concurrently running transactions.

 With ALSM, the Db2 transaction manager identifies long running transactions that could be causing a log full condition and extracts (by copying) their log data from the active log files into separate extraction log

files dedicated for the transaction.

 This allows the original log files to be removed to free up disk space, so that new active log files can be created.

 How it can be enabled?

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 Available starting from Db2 Version 11.5 Mod Pack 4, use Advanced Log Space Management (ALSM) to reduce your likelihood of hitting transaction log full conditions. The feature can be enabled by setting the

DB2_ADVANCED_LOG_SPACE_MGMT registry variable to ON.


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