RMS DFNBC
RMS_DFNBC is a system parameter that specifies a default block count for network access to remote, sequential, indexed sequential, and relative files. The network block count value represents the number of blocks that RMS is prepared to allocate for the I/O buffers used to transmit and receive data. The buffer size used for remote file access, however, is the result of a negotiation between RMS and the remote file access listener (FAL). The buffer size chosen is the smaller of the two sizes presented. Thus, RMS_DFNBC places an upper limit on the network buffer size that is used. It also places an upper limit on the largest record that can be transferred to or from a remote file. In other words, the largest record that can be transferred must be less than or equal to RMS_DFNBC multiplied by 512 bytes. You can set this system parameter with the DCL command SET RMS_DEFAULT/SYSTEM and display the parameter with SHOW RMS_DEFAULT. RMS_DFNBC is an AUTOGEN and DYNAMIC parameter.