RMS DFMBFREL
RMS_DFMBFREL is a system parameter that establishes the default RMS multibuffer count for relative disk operations. This value defines the number of I/O buffers that RMS allocates for each relative file. You can set this system parameter with the DCL command SET RMS_DEFAULT/SYSTEM and display the parameter with SHOW RMS_ DEFAULT. RMS_DFMBFREL is an AUTOGEN and DYNAMIC parameter.