Details

    • Type: New Feature New Feature
    • Status: Closed
    • Priority: Major Major
    • Resolution: Fixed
    • Affects Version/s: None
    • Fix Version/s: 1.4
    • Component/s: jackrabbit-core
    • Labels:
      None

      Description

      There are three main problems with the way Jackrabbit currently handles large binary values:

      1) Persisting a large binary value blocks access to the persistence layer for extended amounts of time (see JCR-314)
      2) At least two copies of binary streams are made when saving them through the JCR API: one in the transient space, and one when persisting the value
      3) Versioining and copy operations on nodes or subtrees that contain large binary values can quickly end up consuming excessive amounts of storage space.

      To solve these issues (and to get other nice benefits), I propose that we implement a global "data store" concept in the repository. A data store is an append-only set of binary values that uses short identifiers to identify and access the stored binary values. The data store would trivially fit the requirements of transient space and transaction handling due to the append-only nature. An explicit mark-and-sweep garbage collection process could be added to avoid concerns about storing garbage values.

      See the recent NGP value record discussion, especially [1], for more background on this idea.

      [1] http://mail-archives.apache.org/mod_mbox/jackrabbit-dev/200705.mbox/%3c510143ac0705120919k37d48dc1jc7474b23c9f02cbd@mail.gmail.com%3e

      1. dataStore.patch
        183 kB
        Thomas Mueller
      2. DataStore.patch
        31 kB
        Jukka Zitting
      3. DataStore2.patch
        216 kB
        Jukka Zitting
      4. dataStore3.patch
        208 kB
        Thomas Mueller
      5. dataStore4.zip
        33 kB
        Thomas Mueller
      6. dataStore5-garbageCollector.patch
        17 kB
        Thomas Mueller
      7. internalValue.patch
        44 kB
        Thomas Mueller
      8. ReadWhileSaveTest.patch
        3 kB
        Jukka Zitting

        Activity

          People

          • Assignee:
            Unassigned
            Reporter:
            Jukka Zitting
          • Votes:
            2 Vote for this issue
            Watchers:
            1 Start watching this issue

            Dates

            • Created:
              Updated:
              Resolved:

              Development