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SCSBUFFCNT is a system parameter that determines the number of buffer descriptors configured for all systems communication architecture (SCA). If an SCA device is not configured on your system, this parameter is ignored. Generally speaking, each data transfer needs a buffer descriptor and thus the number of buffer descriptors can be a limit on the number of possible simultaneous I/Os. Various performance monitors report when a system is out of buffer descriptors for a given workload which is an indication that a larger value for SCSBUFFCNT is worth considering. Note that AUTOGEN provides feedback for this parameter on VAX systems only. On Alpha and Integrity servers, the system communication services (SCS) buffers are allocated as needed, and SCSBUFFCNT is reserved for VSI use only. SCSBUFFCNT has the AUTOGEN, FEEDBACK, and GEN attributes.