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  1. Blazegraph (by SYSTAP)
  2. BLZG-461

AbstractTask uses one TemporaryStoreFactory per read-only or read/write tx task.

    Details

    • Type: New Feature
    • Status: Accepted
    • Resolution: Unresolved
    • Affects Version/s: QUADS_QUERY_BRANCH
    • Fix Version/s: None
    • Component/s: Journal
    • Labels:
      None

      Description

      AbstractTask's IsolatedActionJournal and ReadOnlyJournal classes allocate a TemporaryStoreFactory for each task instance. This could create a very high overhead for full transactions. At stake is whether the temporary store accessible to the task is "isolated", which includes visibility and/or concurrency concerns. The comments in the code suggest that a better solution would be to introduce the concept of isolation into the resource locator mechanism.

        Activity

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        bryanthompson bryanthompson added a comment -

        Actually, the overhead might not be that bad. The temporary store does not create the backing file unless an initial memory buffer becomes full. So small transactions should not touch the disk while large ones would spill to the disk.

        Suggest first benchmarking update throughput with and without full read/write tx. For example, using BSBM UPDATE. Or using a concurrent stress test in the NSS test suite that includes a mixture of updates.

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        bryanthompson bryanthompson added a comment - Actually, the overhead might not be that bad. The temporary store does not create the backing file unless an initial memory buffer becomes full. So small transactions should not touch the disk while large ones would spill to the disk. Suggest first benchmarking update throughput with and without full read/write tx. For example, using BSBM UPDATE. Or using a concurrent stress test in the NSS test suite that includes a mixture of updates.

          People

          • Assignee:
            bryanthompson bryanthompson
            Reporter:
            bryanthompson bryanthompson
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            Dates

            • Created:
              Updated: