IPC:MessageQueueReceive

backend process is waiting to receive a message from an internal shared message queue. This typically happens during inter-process communication (IPC) between PostgreSQL backend processes or auxiliary/worker processes A common scenario is during parallel query execution, where the leader process waits for results or status updates from parallel workers via message queues. It can also occur in replication or logical decoding contexts where processes exchange control messages.

Potential Problem

High percentage of this wait event may indicate issues such as:

Excessive parallelism: Too many workers causing communication bottlenecks
Small result sets: Coordination overhead dominates when workers produce minimal data
CPU saturation: System cannot efficiently handle the number of parallel processes
Slow worker execution: Leader waiting long periods for workers to complete