Package org.apache.flink.runtime.state

Interface LocalSnapshotDirectoryProvider

All Superinterfaces:
Serializable
All Known Implementing Classes:
LocalSnapshotDirectoryProviderImpl
public interface LocalSnapshotDirectoryProvider extends Serializable
Provides directories for local backup or local recovery. It offers access to the allocation base directories (i.e. the root directories for all local state that is created under the same allocation id) and the subtask-specific paths, which contain the local state for one subtask. Access by checkpoint id rotates over all root directory indexes, in case that there is more than one. Selection methods are provided to pick the directory under a certain index. Directory structures are of the following shape: 

 |-----allocationBaseDirectory------|
 |-----subtaskBaseDirectory--------------------------------------|
 |-----subtaskSpecificCheckpointDirectory------------------------------|

 ../local_state_root_1/allocation_id/job_id/vertex_id_subtask_idx/chk_1/(state)
 ../local_state_root_2/allocation_id/job_id/vertex_id_subtask_idx/chk_2/(state)

 (...)

  • Method Summary

    Modifier and Type
    Method
    Description
    File
    allocationBaseDirectory(long checkpointId)
    Returns the local state allocation base directory for given checkpoint id w.r.t. our rotation over all available allocation base directories.
    int
    allocationBaseDirsCount()
    Returns the total number of allocation base directories.
    File
    selectAllocationBaseDirectory(int idx)
    Returns a specific allocation base directory.
    File
    selectSubtaskBaseDirectory(int idx)
    Returns a specific subtask base directory.
    File
    subtaskBaseDirectory(long checkpointId)
    Returns the local state directory for the owning subtask the given checkpoint id w.r.t. our rotation over all available available allocation base directories.
    File
    subtaskSpecificCheckpointDirectory(long checkpointId)
    Returns the local state directory for the specific operator subtask and the given checkpoint id w.r.t. our rotation over all available root dirs.

  • Method Details

    • allocationBaseDirectory

      File allocationBaseDirectory(long checkpointId)
      Returns the local state allocation base directory for given checkpoint id w.r.t. our rotation over all available allocation base directories.

    • subtaskBaseDirectory

      File subtaskBaseDirectory(long checkpointId)
      Returns the local state directory for the owning subtask the given checkpoint id w.r.t. our rotation over all available available allocation base directories. This directory is contained in the directory returned by allocationBaseDirectory(long) for the same checkpoint id.

    • subtaskSpecificCheckpointDirectory

      File subtaskSpecificCheckpointDirectory(long checkpointId)
      Returns the local state directory for the specific operator subtask and the given checkpoint id w.r.t. our rotation over all available root dirs. This directory is contained in the directory returned by subtaskBaseDirectory(long) for the same checkpoint id.

    • selectAllocationBaseDirectory

      File selectAllocationBaseDirectory(int idx)
      Returns a specific allocation base directory. The index must be between 0 (incl.) and allocationBaseDirsCount() (excl.).

    • selectSubtaskBaseDirectory

      File selectSubtaskBaseDirectory(int idx)
      Returns a specific subtask base directory. The index must be between 0 (incl.) and allocationBaseDirsCount() (excl.). This directory is direct a child of selectSubtaskBaseDirectory(int) given the same index.

    • allocationBaseDirsCount

      int allocationBaseDirsCount()
      Returns the total number of allocation base directories.