RMS_DFMBFIDX is a system parameter that establishes the default RMS multibuffer count for indexed sequential disk operations. This value defines the number of I/O buffers that RMS allocates for each indexed file. For sequential access, a larger number that allows some of the index buckets to remain in memory can improve performance. You can set this system parameter with the DCL command SET RMS_DEFAULT/SYSTEM and display the parameter with SHOW RMS_DEFAULT. RMS_DFMBFIDX is an AUTOGEN and DYNAMIC parameter.