Identifying and resolving performance issues caused by TOAST OID contention in Amazon Aurora PostgreSQL Compatible Edition and Amazon RDS for PostgreSQL

This article provides an in-depth exploration of TOAST (The Oversized-Attribute Storage Technique) OID (Object Identifier) contention in PostgreSQL databases, specifically focusing on performance issues in Amazon Aurora PostgreSQL and Amazon RDS for PostgreSQL.

• TOAST is a mechanism for efficiently storing large data types by moving them out of line into a separate table
• PostgreSQL uses OIDs to track database objects, with a maximum limit of 4 billion OIDs
• OID exhaustion can cause significant performance degradation, particularly during insert operations
• Key symptoms include slow insert times and increased latency for TOASTed data operations

The article provides comprehensive guidance on identifying and resolving OID exhaustion, recommending solutions such as data cleanup, archiving, and long-term strategies like table partitioning to manage OID usage effectively.