Key PostgreSQL 16 configuration parameters for performance tuning include:

1. shared_buffers: Sets the amount of memory for shared memory buffers. A starting value could be 25% of system memory on a dedicated database server【37†source】.
2. huge_pages: Controls whether huge pages are used for the main shared memory area, improving performance by reducing CPU time spent on memory management【38†source】.
3. huge_page_size: Determines the size of huge pages when enabled【39†source】.
4. temp_buffers: Specifies the maximum memory for temporary buffers within each session, used for access to temporary tables【40†source】.
5. max_prepared_transactions: Sets the maximum number of transactions in the "prepared" state simultaneously【41†source】.
6. work_mem: Defines the maximum memory used by a query operation before writing to temporary disk files【42†source】.
7. hash_mem_multiplier: Adjusts the maximum memory for hash-based operations, a multiplier of work_mem【43†source】.
8. maintenance_work_mem: Sets the maximum memory for maintenance operations like VACUUM and CREATE INDEX【44†source】.
9. autovacuum_work_mem: Specifies the maximum memory for each autovacuum worker process【45†source】.
10. vacuum_buffer_usage_limit: Defines the buffer access strategy size for VACUUM and ANALYZE commands【46†source】.
11. logical_decoding_work_mem: Limits memory for logical decoding before changes are written to disk【47†source】.
12. max_stack_depth: Sets the maximum depth of the server's execution stack【48†source】.
13. shared_memory_type: Chooses the shared memory implementation for PostgreSQL's shared buffers and data【49†source】.
14. dynamic_shared_memory_type: Specifies the dynamic shared memory implementation used by the server【50†source】.
15. min_dynamic_shared_memory: Allocates memory at startup for parallel queries【51†source】.
16. temp_file_limit: Sets the maximum disk space for temporary files used by a process【52†source】.
17. max_files_per_process: Limits the number of open files per server subprocess【53†source】.
18. vacuum_cost_delay: Determines the sleep time when the vacuum cost limit is exceeded【54†source】.
19. vacuum_cost_page_hit, vacuum_cost_page_miss, vacuum_cost_page_dirty: Estimate costs for vacuum operations【55†source】【56†source】【57†source】.
20. vacuum_cost_limit: Sets the cost limit for vacuum operations【58†source】.
21. bgwriter_delay: Specifies the delay between rounds for the background writer【59†source】.
22. bgwriter_lru_maxpages: Limits the number of buffers written by the background writer per round【60†source】.
23. bgwriter_lru_multiplier: Adjusts the number of dirty buffers written based on recent demand【61†source】.
24. bgwriter_flush_after: Triggers OS to issue writes to storage after a certain amount of data is written【62†source】.
25. backend_flush_after: Forces OS to issue writes after a certain amount of data is written by a backend【63†source】.
26. effective_io_concurrency: Sets the expected number of concurrent disk I/O operations【64†source】.
27. maintenance_io_concurrency: Similar to effective_io_concurrency, but for maintenance work【65†source】.
28. max_worker_processes: Defines the maximum number of background processes the system can support【66†source】.
29. max_parallel_workers_per_gather: Sets the maximum number of workers for a Gather or Gather Merge node【67†source】.
30. max_parallel_maintenance_workers: Limits the number of parallel workers for certain utility commands【68†source】.
31. max_parallel_workers: Sets the overall maximum number of workers for parallel operations【69†source】.
32. parallel_leader_participation: Determines whether the leader process executes the query plan under certain nodes【70†source】.
33. old_snapshot_threshold: Sets the time limit for query snapshots before they risk a “snapshot too old” error.

These parameters offer various ways to fine-tune the performance of PostgreSQL 16, focusing on memory management, I/O optimization, parallel processing, and vacuuming strategies.