A data processing network includes request nodes with local memories accessible as a distributed virtual memory (DVM) and coupled by an interconnect fabric. Multiple DVM domains are assigned, each containing a DVM node for handling DVM operation requests from request nodes in the domain. On receipt of a request, a DVM node sends a snoop message to other request nodes in its domain and sends a snoop message to one or more peer DVM nodes in other DVM domains. The DVM node receives snoop responses from the request nodes and from the one or more peer DVM nodes, and send a completion message to the first request node. Each peer DVM node sends snoop messages to the request nodes in its domain, collects snoop responses, and sends a single response to the originating DVM node. In this way, DVM operations are performed in parallel.