【12c新特性】12c中新后台进程,主要包括但不局限于:  
OFSD Oracle File Server BG
RMON rolling migration monitor
IPC0 IPC Service 0
BW36 db writer process 36
BW99 db writer process 99
TMON Transport Monitor
RTTD Redo Transport Test Driver
TPZ1 Test Process Z1
TPZ2 Test Process Z2
TPZ3 Test Process Z3
LREG Listener Registration
AQPC AQ Process Coord
FENC IOServer fence monitor
VUBG Volume Driver Umbilical Background
SCRB ASM Scrubbing Master
    可以看到这里LREG进程开始负责对Listener Registration监听器的注册: Service registration enables the listener to determine whether a database service and its service handlers are available. A service handler is a dedicated server process or dispatcher that acts as a connection point to a database. During registration, the LREG process provides the listener with the instance name, database service names, and the type and addresses of service handlers. This information enables the listener to start a service handler when a client request arrives. Figure 16-5 shows two databases, each on a separate host. The database environment is serviced by two listeners, each on a separate host. The LREG process running in each database instance communicates with both listeners to register the database.   截止目前12c的官方文档中的配图还有问题, 图示还是用PMON注册监听。 【12c新特性】12c中新后台进程_数据库     Reference: E16655_01/E16655_01/server.121/e17633/dist_pro.htm#CHDIBHAD