Umair Shahid: Challenges with Network Latency in Highly Available PostgreSQL Clusters

Highly available PostgreSQL clusters are an essential component of modern database infrastructures. These clusters provide critical services to organizations that must ensure that their applications have reliable and continuous access to their databases. In such clusters, auto-failover is a crucial feature that ensures that the cluster continues to operate even when one of the nodes fails. However, network latency can pose significant challenges in auto-failover situations. This blog will discuss network latency’s challenges in auto failover situations in highly available PostgreSQL clusters, their causes, prevention, and resolution. What is Auto Failover? Auto failover is a feature of PostgreSQL that allows a standby node to take over the role of the primary node in the event of a failure. This ensures that the service remains available even if the primary node goes down. A highly available PostgreSQL cluster has at least two nodes: a primary node and a standby node. The primary node serves read and write requests from clients, while the standby node is kept in sync with the primary node and takes over in case of a failure. What is Network Latency? Network latency refers to the time delay that occurs when data is transmitted from one point to another over a network. It is measured as the time it takes for a packet of data to travel from the source to the destination and back. Network latency is influenced by many factors, such as the distance between the source and destination, the quality of the network infrastructure, and the number of hops between the nodes. Causes Network latency can be caused by various factors, including: Network Congestion: When multiple users or applications try to access the database simultaneously, it can result in network congestion, causing delays in data transmission. Distance: When the distance between the primary and standby nodes in a PostgreSQL cluster is significant, it can result in latency issues due to the physical distance betwe[...]