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AdministeringIn addition to administering the database server, you can tune performance, replicate data, and archive data.
System administrationThese topics contain concepts, procedures, and reference information for database and database server administrators to use for managing and tuning HCL OneDB™ database servers.
Administrator's GuideThe HCL OneDB™ Administrator's Guide provides the information required to administer HCL OneDB™.
Disk, memory, and process management
Shared memoryThese topics describe the content of database server shared memory, the factors that determine the sizes of shared-memory areas, and how data moves into and out of shared memory.
Flush data to diskWriting a buffer to disk is called buffer flushing.
Flush the logical-log bufferA number of events can cause the logical-log buffer to flush.

Flush the logical-log buffer

A number of events can cause the logical-log buffer to flush.

The database server uses the shared-memory logical-log buffer as temporary storage for records that describe modifications to database server pages. From the logical-log buffer, these records of changes are written to the current logical-log file on disk and eventually to the logical-log backup media. For a description of logical logging, see Logical log.

Five events cause the current logical-log buffer to flush:

The current logical-log buffer becomes full.
A transaction is prepared or committed in a database with unbuffered logging.
A nonlogging database session terminates.
A checkpoint occurs.
A page is modified that does not require a before-image in the physical log.

The following topics explain each of these events in detail.