Using Serviceguard Extension for RAC, 5th Edition, June 2007

Serviceguard Configuration for Oracle 9i RAC
Operating System Parameters
Chapter 3142
Operating System Parameters
The maximum number of Oracle server processes cmgmsd can handle is
8192. When there are more than 8192 server processes connected to
cmgmsd, then cmgmsd will start to reject new requests.
Oracle foreground server processes are needed to handle the requests of
the DB client connected to the DB instance.
Each foreground server process can either be a “dedicated” or a “shared”
server process. In the case of a dedicated process, there is a one-to-one
correspondence between the DB client and the foreground server process
it invokes. The shared server processes can handle multiple DB clients.
In the case where a DB instance is configured to support a large number
of DB clients, it is necessary to adjust the maxfiles parameter. This is to
make sure there are enough file descriptors to support the necessary
number of Oracle foreground and background server processes.