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  1. WiredTiger
  2. WT-2523

LSM index compaction hangs after creating snapshot

    • Type: Icon: Bug Bug
    • Resolution: Won't Fix
    • Priority: Icon: Major - P3 Major - P3
    • None
    • Affects Version/s: None
    • Component/s: None
    • None

      The fuzzer is hanging on code like this in Evergreen:

      var mongod = MongoRunner.runMongod({wiredTigerIndexConfigString: 'type=lsm'});
      
      var res = mongod.getDB('admin').runCommand('makeSnapshot');
      assert.commandWorked(res);
      
      var coll = mongod.getDB('test').foo;
      
      coll.ensureIndex({_id: 1, i: 1});
      coll.insert({a: 1});
      coll.runCommand('compact');
      

      It appears that __wt_lsm_compact is processing one chunk that fails to flush, which causes an infinite loop. I noticed that force flushes are indeed being added to the app queue, but that's about as far as I got with my investigation.

            Assignee:
            backlog-server-storage-engines [DO NOT USE] Backlog - Storage Engines Team
            Reporter:
            kamran.khan Kamran K.
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              Created:
              Updated:
              Resolved: