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  1. Core Server
  2. SERVER-34519

mongo_lock.py generating malformed graphviz output

    • Type: Icon: Bug Bug
    • Resolution: Fixed
    • Priority: Icon: Major - P3 Major - P3
    • 3.7.6
    • Affects Version/s: None
    • Component/s: Testing Infrastructure
    • Labels:
      None
    • Fully Compatible
    • ALL
    • Storage NYC 2018-04-23

      I am running the following in the mongo shell against current master. This opens a multi-statement transaction and then runs a collection drop outside of the transaction which blocks on the stashed transaction resources.

      db.test.drop();
      assert.writeOK(db.test.insert({}, {writeConcern: {w: "majority"}}));
      const session = db.getMongo().startSession({})
      session.startTransaction({readConcern: {level: "snapshot"}})
      const sessionDB = session.getDatabase("test");
      assert.commandWorked(sessionDB.runCommand({find: "test"}));
      db.test.drop();
      

      See the attached screenshot for the result. The graphviz output which generates this is:

      digraph "mongod+lock-status" {
          "Thread 0x7fd29e216700" -> "Lock 0x559449183b00";
          "Lock 0x559449183b00" -> "Thread 0x7fd29e216700";
          "Thread 0x7fd29233f700" -> "Lock 0x559449183b00";
          "Thread 0x7fd29e216700" [label=""conn2" (Thread 0x7fd29e216700 (LWP 16109))" ]
          "Lock 0x559449183b00" [label="Lock 0x559449183b00 (MongoDB lock)" ]
          "Thread 0x7fd29233f700" [label=""clientcursormon" (Thread 0x7fd29233f700 (LWP 16068))" ]
      }
      

            Assignee:
            james.wahlin@mongodb.com James Wahlin
            Reporter:
            james.wahlin@mongodb.com James Wahlin
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              Created:
              Updated:
              Resolved: