maintenance_work_mem: The maintenance_work_mem parameter in PostgreSQL controls the maximum amount of memory used for maintenance operations, such as VACUUM, CREATE INDEX, and ALTER TABLE ADD FOREIGN KEY operations. Unlike work_mem, this setting applies to the total memory used by maintenance tasks, not per operation. Setting it too low may slow down these operations, while too high a setting could impact the overall system performance, especially on systems with limited memory.maintenance_work_mem depends on your system's available memory and the nature of your workload. For systems with ample memory, increasing maintenance_work_mem can speed up maintenance operations and improve system health by more efficiently processing VACUUM operations, thereby reducing table bloat and improving query performance.maintenance_work_mem compared to a server shared with other applications. A general recommendation is to set maintenance_work_mem to a value that allows maintenance tasks to run efficiently (e.g., 1GB-2GB on servers with sufficient memory) while ensuring there's enough memory left for the database to handle its workload effectively. Regular monitoring and adjustments based on operational feedback and maintenance performance are key to optimizing this setting.