There are several hard disk settings that can boost IO performance; however, this boost comes with a penalty. For example, the fsync setting forces each transaction to be written to the hard disk after each commit. Turning this off will increase performance, especially for bulk upload operations. A max_wal_size or checkpoint_segments of small value might lead to a performance penalty in write-heavy systems; on the other hand, increasing the max_wal_size or checkpoint_segments setting to a high value will increase recovery time. 

In specific cases, such as bulk upload operations, performance can be increased by altering hard disk settings, changing the logging configuration to log minimal info, and finally, disabling autovacuuming; however, after the bulk operation is over, one should not forget to reset the server configurations and run the VACUUM ANALYZE command.