This SMB allows a client to tell a server to "watch" a particular directory for any changes and only reply to the SMB request when a change has occurred. Such constant scanning of a directory is expensive under UNIX, hence an smbd 8 daemon only performs such a scan on each requested directory once every change notify timeout seconds. Note that in 3.0.23 this has been changed to a per-share parameter and setting this to zero prevents any change notify directory scans completely on a share. This is to allow this paramter to be set to zero on shares configured for very large directories, where a Windows client will re-scan the entire directory after every delete operation (when deleting many files) due to the change notify triggering. This is an extremely expensive operation on some systems. 60 300Would change the scan time to every 5 minutes.