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Background Processes - Oracle Architecture

SMON - System Monitor 

 Performs recovery after instance failure, monitor temporary segments and extents clean those temporary extents and segments. 

 PMON - Process Monitor

 Failed process resources in shared server architecture monitor and restart any failed dispatcher or server process. 

 DBWn - Database Writer

 Database Writer process writes new or changed data blocks into the data-files which are in the buffer cache. 

 LGWR - Log Writer

 Log writer is in change of REDO Log buffer management log writer is one of most active processes until log writer success data commit will not be completed.

 ARCn - Archive Process
Copies REDO Logs to one or more destinations.

 CKPT - Checkpoint Process

 This helps to reduce the amount of time required for instance recovery. During checkpoint updates the header of the control file and data-files to reflect the last successful System Changed Number (SCN) This automatically starts every time the redo log switch occurs. 

 RECO - Recover Process

 This handles the failures of distributed transactions.

 

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