Examples described herein relate to coalescing one or more messages into a coalesced message and representing one or more fields of the metadata of the one or more messages using one or more codes, wherein at least one of the one or more codes uses fewer bits than that of original metadata fields to compact the metadata fields. In some examples, the metadata includes at least one or more of: a target processing element (PE) number or identifier, message length, operation to perform, target address where to read or write data, source PE number or identifier, initiator address in which to write result data, or message identifier.