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  1. Jackrabbit Oak
  2. OAK-6421

Phase out JCR Locking support

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    • Task
    • Status: Open
    • Major
    • Resolution: Unresolved
    • None
    • None
    • jcr
    • None

    Description

      Oak currently has a lot of gaps in its JCR Locking implementation (see OAK-1962), which basically makes it non-compliant with the JCR specification.

      I propose we phase out the support for JCR Locking because a proper implementation would be rather complex with a runtime behaviour that is very different in a standalone deployment compared to a cluster. In the standalone case a lock could be acquired very quickly, while in the distributed case, the operations would be multiple orders of magnitude slower, depending on how cluster nodes are geographically distributed.

      Applications that rely on strict lock semantics should use other mechanisms, built explicitly for this purpose. E.g. Apache Zookeeper.

      To ease upgrade and migration to a different lock mechanism, the proposal is to introduce a flag or configuration that controls the level of support for JCR Locking:

      • DISABLED: the implementation does not support JCR Locking at all. Methods will throw UnsupportedRepositoryOperationException when defined by the JCR specification.
      • DEPRECATED: the implementation behaves as right now, but logs a warn or error message that JCR Locking does not work as specified and will be removed in a future version of Oak.

      In a later release (e.g. 1.10) the current JCR Locking implementation would be removed entirely and unconditionally throw an exception.

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        Issue Links

          is related to

          Improvement - An improvement or enhancement to an existing feature or task. SLING-7633 make Sling work without JCR locking

          • Major - Major loss of function.
          • Open

          Improvement - An improvement or enhancement to an existing feature or task. SLING-10994 Remove locking of JCR node

          • Major - Major loss of function.
          • Open

          Technical task - A technical task. OAK-4460 Bogus lock token

          • Blocker - Blocks development and/or testing work, production could not run
          • Resolved

          Technical task - A technical task. OAK-3482 Lock object spec compliance issue

          • Major - Major loss of function.
          • Resolved

          Improvement - An improvement or enhancement to an existing feature or task. OAK-5763 Improve LockException message on org.apache.jackrabbit.oak.jcr.lock.LockManagerImpl unlock

          • Major - Major loss of function.
          • Resolved

          Technical task - A technical task. OAK-4234 NodeDelegate: checking for locks should not require read access to system lock properties

          • Minor - Minor loss of function, or other problem where easy workaround is present.
          • Resolved

          Improvement - An improvement or enhancement to an existing feature or task. OAK-9187 LockOperation always calls SessionDelegate.refresh before executing operations

          • Major - Major loss of function.
          • Closed
          relates to

          Bug - A problem which impairs or prevents the functions of the product. OAK-1962 Fix and Improve Locking

          • Major - Major loss of function.
          • Open

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              Unassigned Unassigned
              mreutegg Marcel Reutegger
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              Dates

                Created:
                Updated: