New Background Processes In Oracle Database 12c

The post provides information on new background processes introduced in 12c.

Background Process	Description
BWnn	Database Writer Processes
FENC	Fence Monitor Process
IPC0	IPC Service Background Process
LDDn	Global Enqueue Service Daemon Helper Slave
LGnn	Log Writer Worker
LREG	Listener Registration Process
OFSD	Oracle File Server Background Process
RPOP	Instant Recovery Repopulation Daemon
SAnn	SGA Allocator
SCRB	ASM Disk Scrubbing Master Process
SCRn	ASM Disk Scrubbing Slave Repair Process
SCVn	ASM Disk Scrubbing Slave Verify Process

BWnn – Database Writer Processes

There can be 1 to 100 Database Writer Processes. The names of the first 36 Database Writer Processes are DBW0-DBW9 and DBWa-DBWz. The names of the 37th through 100th Database Writer Processes are BW36-BW99. The database selects an appropriate default setting for the DB_WRITER_PROCESSES parameter or adjusts a user-specified setting based on the number of CPUs and processor groups.

FENC – Fence Monitor Process

FENC Processes fence requests for RDBMS instances which are using Oracle ASM instances.

IPC0 – IPC Service Background Process

Common background server for basic messaging and RDMA primitives based on IPC (Inter-process communication) methods.

LDDn – Global Enqueue Service Daemon Helper Slave

Helps the LMDn processes with various tasks.

LGnn – Log Writer Worker

On multiprocessor systems, LGWR creates worker processes to improve the performance of writing to the redo log. LGWR workers are not used when there is a SYNC standby destination. Possible processes include LG00-LG99.

LREG – Listener Registration Process

Registers the instance with the listeners.

OFSD – Oracle File Server Background Process

Serves file system requests submitted to an Oracle instance.

RPOP – Instant Recovery Repopulation Daemon

Responsible for re-creating and/or repopulating data files from snapshot files and backup files.

SAnn – SGA Allocator

Allocates SGA. The SAnn process allocates SGA in small chunks. The process exits upon completion of SGA allocation.

SCRB – ASM Disk Scrubbing Master Process

Coordinates Oracle ASM disk scrubbing operations.

SCRn – ASM Disk Scrubbing Slave Repair Process

Performs Oracle ASM disk scrubbing repair operation.

SCVn – ASM Disk Scrubbing Slave Verify Process

Performs Oracle ASM disk scrubbing verify operation.