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APPLIES TO:@H_502_19@ Oracle Database - Enterprise Edition - Version 12.1.0.1 and later
Information in this document applies to any platform.

PURPOSE@H_502_19@

This article provides information onnewbackground processes introduced in 12c

A complete list of background processes can be found in the Oracle Documentation:
https://docs.oracle.com/database/121/REFRN/GUID-86184690-5531-405F-AA05-BB935F57B76D.htm#REFRN104

DETAILS@H_502_19@

* BWnn 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) 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.