Uploaded image for project: 'Ignite'
  1. Ignite
  2. IGNITE-10862

Introduce tool to free up space on a disc of unused memory pages

    XMLWordPrintableJSON

    Details

    • Type: Improvement
    • Status: Open
    • Priority: Critical
    • Resolution: Unresolved
    • Affects Version/s: 2.7
    • Fix Version/s: None
    • Component/s: persistence
    • Labels:
      None
    • Ignite Flags:
      Docs Required, Release Notes Required

      Description

      At the current time, Ignite is not able to release occupied disc space even if a significant amount of data was removed from IgniteCache. It disturbs our users because they can't use hardware effectively, also it increases TCO.

      Use-cases:

      Let's imagine that we have used IgniteCache with enabled PDS during the time:

      • hardware disc space has been occupied during growing up of an amount
        of data, e.g. 100Gb;
      • then, we removed non-actual data, e.g 50Gb, which became useless for us;
      • disc space stopped growing up with new data, but it was not
        released, and still took 100Gb, instead of expected 50Gb;

      Another use case:

      • a user extracts data from IgniteCache to store it in separate
        IgniteCache or another store;
      • disc still is occupied and the user is not able to store data in the
        different cache at the same cluster because of disc limitation;

      Possible solutions:

      Introduce some kind of mechanics which will be able to shrink data in IgniteCache and to free up space on a disc of mapped free memory pages.

      A solution should take into account possible concurrent reads and updates of data and indexes to maintain consistency.

      Maybe, it makes sense to implement a tool to be offline at the first step that means concurrent operations will be prohibited. 

      Strongly recommended discussing design on dev-list with Ignite experts before the start of implementation.

        Attachments

          Issue Links

            Activity

              People

              • Assignee:
                Unassigned
                Reporter:
                daradurvs Vyacheslav Daradur
              • Votes:
                2 Vote for this issue
                Watchers:
                7 Start watching this issue

                Dates

                • Created:
                  Updated: