anchor.diff:      member val Memory             = Nullable<double>() with get, set
       member val NetworkUp          = Nullable<double>() with get, set
       member val NetworkDown        = Nullable<double>() with get, set
  +    member val Version            = Unchecked.defaultof<string> with get, set
   
       new () = new WorkerRecord(null, null, null, nullableDefault, null, Unchecked.defaultof<_>, nullableDefault)
   
  
positive.code:       /// Network upload (kbps).
        NetworkUp : double
        /// Network download (kbps).
        NetworkDown : double } 
      
      override this.GetHashCode() = hash this.Id
      override this.Equals(other:obj) =
  
negative.code:                 w.UpdateCounters(perfMon.Value.GetCounters())
                  w.ActiveJobs <- nullable 0
                  w.IsActive <- nullable true
                  w.Version <- ReleaseInfo.localVersion.ToString(4)
                  w.MaxJobs <- match maxJobs with None -> nullableDefault | Some mj -> nullable mj
                  do! Table.insertOrReplace<WorkerRecord> config table w //Worker might restart but keep id.
                  current := Some w
  