pragma Debug (Trace_Usage (9, P'Unchecked_Access, "Stop"));
      Used := Now - P.Last_Usage_Update_Time;
      pragma Assert (Used >= 0);
      P.Usage := P.Usage + Used;
      R := P.R_Queue.Front_Of;

      pragma Debug (Check_Usage
                    (3, P'Unchecked_Access, R.R_Amount, "Suspend"));

      if P.T.Is_Suspended then
         --  Compute the replenishment.
         P.R_Queue.Pop;
         if P.Usage < R.R_Amount then
            --  Split the chunk.
            --  R2 is the unused part.
            R2.R_Amount := R.R_Amount - P.Usage;
            R2.R_Time := R.R_Time;
            Trace (0, "R.R_time = "
                     & Time'Image (R.R_Time));
            P.R_Queue.Add (R2);
         end if;
         --  R is the used part.
         R.R_Amount := P.Usage;
         R.R_Time := P.T.Priority;
         P.R_Queue.Add (R);
         P.Usage := 0;
         --  Check for new chunks
         R := P.R_Queue.Front_Of;
         P.T.Priority := R.R_Time + P.Parms.Budget_Interval;
         if R > Now then
            -- Schedule a replenishment event.
         end if;
         pragma Debug (Check_R_Sum (P.R_Queue,
                                    P.Parms.Budget,
                                    "Suspend"));
      end if;