When using the core database APIs, you typically run applications and FairCom Servers on the same computer. FairCom automatically uses shared memory to communicate between them because it provides up to 5x faster performance than TCP/IP. When applications and c-tree Servers run on different computers, communications automatically occur over TCP/IP.
You can change how the FairCom Server connects to the core database APIs by using the COMM_PROTOCOL keyword in a ctsrvr.cfg file.
The default setting for core database API communications automatically connects using shared memory when applications and the c-tree Server run on the same computer and automatically connects over TCP/IP when applications and the c-tree Server run on different computers. This default setting in ctsrvr.cfg is:
COMM_PROTOCOL F_TCPIP
COMM_PROTOCOL FSHAREMM
It is unlikely that you would want to, but you can force all core database API communications to use TCP/IP by setting only:
COMM_PROTOCOL F_TCPIP
Note: The COMM_PROTOCOL option specifies the protocol used for NAV, ISAM, and Low-level API connections.
By default, local SQL connections use shared memory because it is the fastest protocol. If you want to force TCP/IP communications for SQL, set SQL_OPTION NO_SHARED_MEMORY in ctsrvr.cfg. See COMM_PROTOCOL for more information about the communication protocol for SQL connections.