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  1. Cassandra
  2. CASSANDRA-9754

Make index info heap friendly for large CQL partitions

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Details

    • Improvement
    • Status: Awaiting Feedback
    • Low
    • Resolution: Unresolved
    • 4.x
    • Legacy/Core
    • None

    Description

      Looking at a heap dump of 2.0 cluster, I found that majority of the objects are IndexInfo and its ByteBuffers. This is specially bad in endpoints with large CQL partitions. If a CQL partition is say 6,4GB, it will have 100K IndexInfo objects and 200K ByteBuffers. This will create a lot of churn for GC. Can this be improved by not creating so many objects?

      Attachments

        1. 0f8e28c220fd5af6c7b5dd2d3dab6936c4aa4b6b.patch
          5 kB
          Jeff Jirsa
        2. gc_collection_times_with_birch.png
          172 kB
          Michael Kjellman
        3. gc_collection_times_without_birch.png
          260 kB
          Michael Kjellman
        4. gc_counts_with_birch.png
          114 kB
          Michael Kjellman
        5. gc_counts_without_birch.png
          107 kB
          Michael Kjellman
        6. perf_cluster_1_with_birch_read_latency_and_counts.png
          78 kB
          Michael Kjellman
        7. perf_cluster_1_with_birch_write_latency_and_counts.png
          77 kB
          Michael Kjellman
        8. perf_cluster_2_with_birch_read_latency_and_counts.png
          83 kB
          Michael Kjellman
        9. perf_cluster_2_with_birch_write_latency_and_counts.png
          80 kB
          Michael Kjellman
        10. perf_cluster_3_without_birch_read_latency_and_counts.png
          99 kB
          Michael Kjellman
        11. perf_cluster_3_without_birch_write_latency_and_counts.png
          109 kB
          Michael Kjellman

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              mkjellman Michael Kjellman
              kohlisankalp Sankalp Kohli
              Michael Kjellman
              Branimir Lambov
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              Dates

                Created:
                Updated: