Difference between revisions of "File locks"

From CRIU
Jump to: navigation, search
(rewording)
m
 
Line 1: Line 1:
Some app may use file locks for synchronization. Generally they will use flock or POSIX file locks, which were achieved by <code>flock</code> or <code>fcntl</code> 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 <code>--file-locks</code> 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).
+
Some app may use file locks for synchronization. Generally they will use flock or POSIX file locks, which were achieved by <code>flock</code> or <code>fcntl</code> 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 {{Opt|--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:
 
Currently supported lock types are:

Latest revision as of 10:43, 22 February 2017

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