File locks

Some app may use file locks for synchronization. Generally they will use flock or POSIX file locks, which were achieved by flock or fcntl system calls. For dump/restore, it is hard to be handled perfectly, because we can't guarantee all potential users are dumped for a specific file lock. Right now, we assume that all file lock users are taken into dump, and the --file-locks option should be used on both dump and restore stages if our app may use any file locks. Remember that file locks dump/restore can only be absolutely safe for container dumping (as a container, naturally, contains all the file locks users).

Currently supported lock types are:

• flock() locks
• POSIX (fcntl) locks

In future releases, we plan to also support:

• file leases
• OFD locks
• mandatory locks