PostgreSQL 10 Administration Cookbook - Fourth Edition

Practical aspects

Since we refer to the transfer of replicated data as streaming, it becomes natural to talk about the flow of data between nodes as if it were a river or stream. Cascaded data can flow through a series of nodes to create complex architectures. From the perspective of any node, it may have downstream nodes that receive replicated data from it and/or upstream nodes that send data to it. Practical limits need to be understood to allow us to understand and design replication architectures.

After a transaction commits on the master, the time taken to transfer data changes to a remote node is usually referred to as the latency, or replication delay. Once the remote node has received the data, changes must then be applied to the ...