Class CombinedDeletionPolicy

java.lang.Object
org.apache.lucene.index.IndexDeletionPolicy
org.elasticsearch.index.engine.ElasticsearchIndexDeletionPolicy
org.elasticsearch.index.engine.CombinedDeletionPolicy

public class CombinedDeletionPolicy extends ElasticsearchIndexDeletionPolicy
An IndexDeletionPolicy that coordinates between Lucene's commits and the retention of translog generation files, making sure that all translog files that are needed to recover from the Lucene commit are not deleted.

In particular, this policy will delete index commits whose max sequence number is at most the current global checkpoint except the index commit which has the highest max sequence number among those.

  • Method Details

    • onInit

      public void onInit(List<? extends org.apache.lucene.index.IndexCommit> commits) throws IOException
      Specified by:
      onInit in class org.apache.lucene.index.IndexDeletionPolicy
      Throws:
      IOException
    • onCommit

      public void onCommit(List<? extends org.apache.lucene.index.IndexCommit> commits) throws IOException
      Specified by:
      onCommit in class org.apache.lucene.index.IndexDeletionPolicy
      Throws:
      IOException
    • getDocCountOfCommit

      protected int getDocCountOfCommit(org.apache.lucene.index.IndexCommit indexCommit) throws IOException
      Throws:
      IOException
    • getSafeCommitInfo

      public SafeCommitInfo getSafeCommitInfo()
      Specified by:
      getSafeCommitInfo in class ElasticsearchIndexDeletionPolicy
      Returns:
      information about the safe commit
    • acquireIndexCommit

      public org.apache.lucene.index.IndexCommit acquireIndexCommit(boolean acquiringSafeCommit)
      Captures the most recent commit point lastCommit or the most recent safe commit point safeCommit. Index files of the capturing commit point won't be released until the commit reference is closed.
      Specified by:
      acquireIndexCommit in class ElasticsearchIndexDeletionPolicy
      Parameters:
      acquiringSafeCommit - captures the most recent safe commit point if true; otherwise captures the most recent commit point.
    • wrapCommit

      protected org.apache.lucene.index.IndexCommit wrapCommit(org.apache.lucene.index.IndexCommit indexCommit)
    • wrapCommit

      protected org.apache.lucene.index.IndexCommit wrapCommit(org.apache.lucene.index.IndexCommit indexCommit, boolean acquiredInternally)
    • releaseIndexCommit

      public boolean releaseIndexCommit(org.apache.lucene.index.IndexCommit acquiredCommit)
      Releases an index commit that acquired by acquireIndexCommit(boolean).
      Specified by:
      releaseIndexCommit in class ElasticsearchIndexDeletionPolicy
      Returns:
      true if the acquired commit can be clean up.
    • findSafeCommitPoint

      public static org.apache.lucene.index.IndexCommit findSafeCommitPoint(List<org.apache.lucene.index.IndexCommit> commits, long globalCheckpoint) throws IOException
      Find a safe commit point from a list of existing commits based on the supplied global checkpoint. The max sequence number of a safe commit point should be at most the global checkpoint. If an index was created before 6.2 or recovered from remote, we might not have a safe commit. In this case, this method will return the oldest index commit.
      Parameters:
      commits - a list of existing commit points
      globalCheckpoint - the persisted global checkpoint from the translog, see Translog.readGlobalCheckpoint(Path, String)
      Returns:
      a safe commit or the oldest commit if a safe commit is not found
      Throws:
      IOException
    • hasAcquiredIndexCommitsForTesting

      public boolean hasAcquiredIndexCommitsForTesting()
      Checks whether the deletion policy is holding on to externally acquired index commits
      Specified by:
      hasAcquiredIndexCommitsForTesting in class ElasticsearchIndexDeletionPolicy
    • hasUnreferencedCommits

      public boolean hasUnreferencedCommits()
      Checks if the deletion policy can delete some index commits with the latest global checkpoint.
      Specified by:
      hasUnreferencedCommits in class ElasticsearchIndexDeletionPolicy
    • commitDescription

      public static String commitDescription(org.apache.lucene.index.IndexCommit commit) throws IOException
      Returns a description for a given IndexCommit. This should be only used for logging and debugging.
      Throws:
      IOException