File locks

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Revision as of 16:10, 20 September 2016 by Xemul (talk | contribs)
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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 we should use the --file-locks option on both dump and restore stages if our app may use any file locks. Remember that file locks dump/restore is only safe for container dumping in theory.

Supported lock types are

  • flock() locks
  • posix (fcntl) locks

In plans

  • file leases
  • OFD locks
  • mandatory locks