System Monitor (SMON) The system monitor performs instance recovery at instance STARTUP. In a multiple instance system (one that uses the Parallel Server), SMON of one instance can also perform instance recovery for other instances that have failed.

SMON also cleans up temporary SEGMENTS that are no longer in USE and recovers dead transactions skipped during CRASH and instance recovery because of file–read or offline errors.

These transactions are eventually recovered by SMON when the tablespace or file is brought back online. SMON also coalesces free extents within the database to make free space contiguous and easier to ALLOCATE.

System Monitor (SMON) The system monitor performs instance recovery at instance startup. In a multiple instance system (one that uses the Parallel Server), SMON of one instance can also perform instance recovery for other instances that have failed.

SMON also cleans up temporary segments that are no longer in use and recovers dead transactions skipped during crash and instance recovery because of file–read or offline errors.

These transactions are eventually recovered by SMON when the tablespace or file is brought back online. SMON also coalesces free extents within the database to make free space contiguous and easier to allocate.