DB2 Version 9.7 for Linux, UNIX, and Windows

Log sequence numbers

A log sequence number (LSN) represents the offset, in bytes, of a log record from the beginning of a database log file. It identifies the location within the log file of a specific log file record.

LSNs are used by many components throughout the DB2®product to maintain database consistency and integrity. The play a critical role in, among other things, commit and rollback operations, crash recovery, and the synchronization of database operations in partitioned database environments.

The rate of growth of LSNs in the log files is directly associated with database activity. That is, as transactions take place, and entries are written to log files, LSNs continually increase. When there is more activity in the database, LSNs grow more quickly.