Serialize updates to the shared backup and its metadata.
The lock records its owner's pid. A lock whose owner is gone is taken over, and the action gets the dead owner's pid so it can repair what that owner left half done.
Serialize updates to the shared backup and its metadata.
The lock records its owner's pid. A lock whose owner is gone is taken over, and the action gets the dead owner's pid so it can repair what that owner left half done.