Type ASSEMBLE
Source Lines : 1,735
Fixes Applied : 5
Most Recent Version : Thursday, December 7, 1978
Last Fix ID : [HRC066DK]

Module

       DMKSCH

Function

       TO MAINTAIN QUEUES OF RUNNABLE AND ELIGIBLE USERS, TO ALTER
       USERS DISPATCHING STATUS, AND TO PERIODICALLY RECALCULATE
       USERS WORKING SET AND DISPATCHING PRIORITY, AND TO MAINTAIN
       STATISTICS ON UTILIZATION AND CONTENTION FOR MAJOR RESOURCES

       DMKSCH ALSO CONTAINS THE ROUTINES THAT MAINTAIN THE SYSTEM TOD
       CLOCK COMPARATOR REQUEST QUEUE AND THE CODE THAT MONITORS FAV-
       ORED EXECUTION USERS

Attributes

       SERIALLY REUSABLE, RESIDENT, CALLED VIA BALR

Operation

    A. MAIN STATUS CHANGE MAINTENANCE
       1. STAMP/UNSTAMP USER'S "REAL" TIMER(S)
       2. IF USER IS RUNNABLE, SKIP TO STEP 6.
       3. IF USER WAS RUNNABLE BEFORE, MARK NOT RUNNABLE
          IF IN ELIGIBLE LIST DROP FROM LIST.
       4. IF USER IS IN AN IDLE WAIT STATE, DROP FROM Q
       5. GO TO SECTION B TO LOOK FOR ELIGIBLE USERS TO ADD TO Q
       6. IF USER IS RUNNABLE, MARK IT RUNNABLE.
       7. IF USER WAS RUNNABLE BUT NOT IN Q BEFORE, GO TO SECTION
          B TO LOOK FOR USERS TO ADD TO Q
       8. IF USER WAS NOT RUNNABLE BEFORE, ADD TO APPROPRIATE RUN-
          NABLE LIST
       9. IF USER'S TIME SLICE HAS BEEN EXCEEDED, DROP FROM Q
      10. IF USER HAS GONE COMPUTE BOUND, DROP TO LOW PRIORITY
      11. GO TO SECTION B

Calls to Other Routines

       DMKMIDNT - CALLED TO ALTER DATE AT MIDNIGHT
       DMKFRET - TO RELEASE STORAGE
       DMKQCNWT - TO WRITE OVERLOAD DIAGNOSTICS TO OPERATOR.
       DMKPTRRS      COUNT REF. PAGES AND ADD TO FLUSH LIST
       DMKLOKSP - TO OBTAIN SPIN LOCKS