Oracle SMON stands for system monitor process.

Hi All a quick discussion on SMON  Important Oracle Background Process.

- SMON stands for system monitor process.
-SMON is the heart of oracle architecture.It monitors the activities of all background process.
- It is a mandatory background process for running an Oracle instance.
- It performs recovery (rollback & rollforward), especially at instance startup.
-It checks the space of SYSTEM tablepace and if it is running short of it displays an error message.
-It also removes the unwanted data from UNDO after commit after the time interval specified by UNDO_RETENTION parameter.
- Also responsible for cleaning up TEMPORARY segments that are no longer in use.
- coalesces contiguous areas of free space.
- In RAC, the SMON process of one instance can perform instance recovery for a failed CPU or instance as well.
- To view its running, grep it on Linux: ps -ef | grep smon

Thanks

Ghufran

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