Question & Answer
Question
When does LOGSECOND parameter takes effect after updating the value ?
Cause
By default LOGSECOND is a dynamic parameter which can be changed immediately online.
But there are times that the LOGSECOND parameter will not be updated immediately.
Here is one example :
db2 update db cfg for sample using LOGSECOND 220
DB20000I The UPDATE DATABASE CONFIGURATION command completed successfully.
SQL1363W One or more of the parameters submitted for immediate modification were not changed dynamically. For these configuration parameters, all applications must disconnect from this database before the changes become effective.
Answer
Cases where this may happen
- If the new LOG SECOND value is <= the number of secondary logs currently allocated by the engine then the update will be deferred.
Suppose that LOG PRIMARY was not sufficient to satisfy the workload and the engine allocated 11 secondary logs.You can only change LOGSECOND to a to a value greater than 11 LOGS. So, for any new value less or equal to 11 LOGS, the update of the new value will not take effect immediately.
- If infinite logging is set then the oldest transaction must be in the current log. If the oldest transaction is not in the current log then the update will be deferred. A long transaction can cause the oldest transaction to not be in the current log.
- If infinite logging is set and total log space in use is > half of total space in all logs currently allocated then the update will be deferred.
- Another situation where the update of LOGSECOND will not take effect immediately is if you are not connected to the db.
You can use "db2pd -logs" to monitor the number of logs allocated and log space used.
Related Information
Was this topic helpful?
Document Information
Modified date:
16 June 2018
UID
swg21568468