In a cluster environment using Samba and ctdb it is critical that locks on central ctdb-hosted databases like locking.tdb are not held for long. With the current Samba architecture it happens that Samba takes a lock and while holding that lock makes file system calls into the shared cluster file system. This option makes Samba warn if it detects that it has held locks for the specified number of milliseconds. If this happens, smbd will emit a debug level 0 message into its logs and potentially into syslog. The most likely reason for such a log message is that an operation of the cluster file system Samba exports is taking longer than expected. The messages are meant as a debugging aid for potential cluster problems. The default value of 0 disables this logging. 0