work_mem: The work_mem parameter in PostgreSQL controls the amount of memory used for internal sort operations and hash tables before writing to temporary disk files. This setting is per-sort/hash operation, meaning multiple operations could potentially use multiple times the work_mem amount. A too-low setting might result in frequent disk writes, slowing down query performance, while a too-high setting can lead to excessive memory consumption, possibly affecting overall server stability.work_mem might be sufficient. For OLAP systems dealing with complex queries and large datasets, a higher work_mem can significantly improve performance by minimizing disk I/O for sorts and joins.pg_stat_statements to identify queries that are spilling to disk, and gradually increase work_mem until you see diminishing returns or until you reach the physical memory limits of your system. Remember, work_mem is allocated for each operation that needs it, so its total usage can multiply quickly in concurrent environments.work_mem can improve query performance, setting it too high can lead to out-of-memory conditions, especially on systems running multiple concurrent queries. It's crucial to balance the need for performance with overall system stability. A common strategy is to set work_mem to a value that optimizes the performance of most queries without jeopardizing the server's health, considering total RAM, expected concurrency, and the nature of the workload. Regularly review query performance and adjust as necessary, taking care not to allocate more than 25-50% of the system's RAM to work_mem under peak load scenarios.