As normal MySQL tmp directory may be located on tmpfs file directory, one may wish to have slave thread tmp directory in different location so slave (=replicated) temporary tables will not be lost on server restart. Note that even after this task is done, slave temporary tables will still be lost after mysqld's restart (because at restart we don't know the table's name). This will be fixed later. For now, having a separate disk-based tmpdir for the slave thread instead of the tmpfs normal tmpdir guarantees that the tmp files created by the replication of LOAD DATA INFILE are not lost when the machine reboots. And it's also a progress to not lose the temp tables. We already have --slave-load-tmpdir, so the solution is: * rename --slave-load-tmpdir to --slave-tmpdir (keep the old name for compatibility) * use --slave-tmpdir in place of --tmpdir everywhere in the slave thread * update the manual.