IntelĀ® Trace Collector 9.1 Update 2 User and Reference Guide
CLUSTER <triplets> [on|off|no|discard]
VT_CLUSTER
Same as PROCESS, but filters are based on the host number of each process. Hosts are distinguished by their name as returned by MPI_Get_processor_name() and enumerated according to the lowest rank of the MPI processes running on them.