title: Log file includes field: "lsid"
body: <p>I have the following log row in my Mongodb log file:</p>
  
  <blockquote>
    <p>2019-09-28T14:13:35.668+0000 I COMMAND  [conn19] command shop.$cmd
    command: update { update: "Task", ordered: true, $db: "shop", lsid: {
    id: UUID("04c9ce6d-af4b-49b8-a351-d38ee3f2b12a") } } numYields:0
    reslen:44 locks:{ Global: { acquireCount: { r: 3, w: 3 } }, Database:
    { acquireCount: { w: 3 } }, Collection: { acquireCount: { w: 3 } },
    Metadata: { acquireCount: { W: 1 } } } protocol:op_msg 923ms</p>
  </blockquote>
  
  <p>I cannot find any information about the "lsid" field that is in the log. Can anyone explain what it is and how it can help me understand this command log? I have many rows that have it.</p>