Background Process

Background Process

An Oracle instance is the combination of the background processes and memory structures. The relationship between the physical and memory structures is maintained and enforced by Oracle’s background processes.Background processes perform functions on behalf of the invoking process. They consolidate functions that would otherwise be handled by multiple Oracle programs running for each user. The background processes perform input/output (I/O) and monitor other Oracle processes to provide increased parallelism for better performance and reliability. Many other processes exist that are used by other options within Oracle, such as Advanced Queuing, Real Application Clusters, Shared Server, Advanced Replication, and so on. The background processes in an Oracle instance can include the following:

Database Writer Process (DBWn)

Log Writer Process (LGWR)

Checkpoint Process (CKPT)

System Monitor Process (SMON)

Process Monitor Process (PMON)


Optional Background Process:

Recoverer Process (RECO)

Archiver Processes (ARCn)

Queue Monitor Processes (QMNn)