The log area is dimensioned when the database is created. A full log area can cause the database to hang.
Monitor the log area. Use the following displays:
DBA Cockpit, Log Area
Database/liveCache Alert Monitor, Log Area
Database/liveCache Assistant, Log Area
Database Assistant, Database Fill Level
Monitor the database logs. To do this, use the Current Messages display, for example (DBA Cockpit/Database/liveCache Assistant).
Monitor the tasks. To do this, use, for example, the Task Manager (DBA Cockpit/Database/liveCache Assistant).
Monitor the log backup and the archiving for the backup files. To do this, use the DBA History display, for example (DBA Cockpit/Database/liveCache Assistant).
A red alert is generated in the Database/live Cache Alert Monitor if the amount of free space in the log area falls below 10%.
Messages warning that the log area is about to fill up are written to the database logs even before the log area is actually full (from a fill level of about 50%):
2006-08-14 09:26:36 0x7EC WRN 52438 LOG log used 50(499 pages left)
If the log area is actually full, one task has the LOG_FULL state and the other tasks have the Vsuspend state until more space becomes available. The task states are logged in the kernel log knldiag.
If the log area is at risk of filling up, you must create a backup log right away (Starting an Action Immediately). The suspended tasks continue with their work as soon as the first log segment is backed up.
You can decide whether a new log volume needs to be added. To do this, use one of the database tools (for example, Database Studio, Adding Log Volumes). For SAP liveCache databases, you can also use the liveCache Assistant: Configuring Log Areas.
Activate the automatic log backup (see Activating Automatic Log Backups). This guarantees regular backups of entries in the log area.
Check regularly that automatic log backup is activated. To do this, use the System Settings display (DBA Cockpit/Database/liveCache Assistant) or the Log Area display in the Database/liveCache Alert Monitor.
Note
Also monitor the data area regularly. Follow the procedure described in Monitoring the Data Area.
Executing Performance Analysis in CCMS
DBA Planning Calendar, Scheduling Concept
Database Administration, Regular Administration Tasks, Backing Up Log Entries, Monitoring Databases
Concepts of the Database System, Tasks