Page History

interface ShuffleMaster<T extends ShuffleDescriptor> extends AutoCloseable {

    // other methods

    /**
     * Whether the shuffle master supports taking snapshot in batch scenarios, which will be used
     * when enable Job Recovery. If it returns true, we will call {@link #snapshotState} to take
     * snapshot, and call {@link #restoreState} to restore the state of shuffle master.
     */
    default boolean supportsBatchSnapshot() {
        return false;
    }
 
    default void snapshotState(
            CompletableFuture<ShuffleMasterSnapshot> snapshotFuture,
            ShuffleMasterSnapshotContext context) {
        snapshotFuture.complete(null);
    }
 
    default void restoreState(List<ShuffleMasterSnapshot> snapshots) {} 
}

interface ShuffleMasterSnapshot extends Serializable { /**
 * This class represents a snapshot of shuffle master, which can be used to restore the internal
 * state of the shuffle master. It is full or incremental.
 */
interface ShuffleMasterSnapshot extends Serializable {

    /** Returns whether the snapshot is incremental. */
    boolean isIncremental();
}

/**
 * Snapshot context used to create {@link ShuffleMasterSnapshot}, which can provide necessary
 * informations.
 */
interface ShuffleMasterSnapshotContext {
}