Uploaded image for project: 'Apache Ozone'
  1. Apache Ozone
  2. HDDS-6722

Memory leak after updating to RocksDB 7

    XMLWordPrintableJSON

Details

    • Bug
    • Status: Resolved
    • Blocker
    • Resolution: Fixed
    • 1.3.0
    • 1.3.0
    • None

    Description

      After HDDS-6456 updated RocksDB version from 6.25.3 to 7.0.4, we started to experience OOM at Ozone Manager very quickly.

      In our test environment, the OM memory stayed at around 3GB. But after that, OM memory quickly increase to over 100GB and crashed within 2 hours.

      After some investigation and discussion with the RocksDB developers (https://github.com/facebook/rocksdb/issues/9962) we were able to isolate the issue to this particular breaking change: https://github.com/facebook/rocksdb/commit/99d86252b

      Prior to the change, RocksDB 6 automatically reclaims native memory when the corresponding Java object is garbage collected. After the change (RocksDB 7), applications must proactively close the objects unused.

      The biggest offenders are the RocksIterator. But there are many others. I'll file jira to clean up their usage. Unfortunately, SonarCloud doesn't seem to detect these unclosed objects.

      Attachments

        1. om rocksdb crash.png
          277 kB
          Wei-Chiu Chuang

        Issue Links

          There are no Sub-Tasks for this issue.

          Activity

            People

              duongnguyen Duong
              weichiu Wei-Chiu Chuang
              Votes:
              0 Vote for this issue
              Watchers:
              3 Start watching this issue

              Dates

                Created:
                Updated:
                Resolved: