II05264: ASVT SLOT USAGE, POSSIBLE ABORTED LOGON COMMANDS.

APAR status

• Closed as user error.

Error description

• The customer receives error message(s) when an address space
  is being created. The message(s) may include:
     msgIKT00203I ADDRESS SPACE CREATION FAILED
     msgIEE328I "LOGON COMMAND ABORTED"
     msgIEA061E REPLACEMENT ASID SHORTAGE HAS BEEN DETECTED
     msgIEA602I ADDRESS SPACE CREATE FAILED.
                  MAXUSERS WOULD HAVE BEEN EXCEEDED.
   The message IEA602I, IEE328I or IKT00203I symptoms usually
  indicate that the system has run out of slots in the ASVT
  (Address Space Vector Table), the supervisor table which maps
  ASID's to ASCB's.  The Size of this table, and thus the
  total number of ASIDs that can initialized until the system
  is re-ipl'd is determined during IPL by the values specified
  in the MAXUSER, RSVNONR, and RSVSTRT options of the IEASYSxx
  parmlib member.
   The total number of address spaces that can be initialized at
  one time, during the life of an IPL is controlled by the total
  of IEASYSxx parameters MAXUSER and RSVSTRT. When any new ASID
  is to be started, Supervisor first determines if there are any
  slots available for the ASID on the ASVT MAXUSER queue. If the
  MAXUSER queue is filled, and if then the address space to be
  started is a started task, the ASVT slot may be satisfied from
  an unused slot on the RSVSTRT queue. If there are no slots
  available on either MAXUSER or RSVSTRT queues the address space
  will not be initialized.
   If the ASVT MAXUSER queue is filled and the ASID being
  initialized is a TSO user, msgIEE328I and msgIEA602I will be
  seen. Normally, when an address space ends, if no cross memory
  binds exist, the ASVT slot is returned to the MAXUSER queue.
  Thus, for each logoff that occurs, one logon should be allowed.
  However, if the total MAXUSER has been reached, subsequent
  logon attempts will again result in the IEE328I and IEA602I
  messages being issued. An IPL is usually the only way to
  alleviate the problem.  Additionally, IKT00203I may be seen.
   The RSVNONR specification reserves a number of ASVT slots to
  replenish ASVT slots in the MAXUSER or RSVSTRT 'pools' which
  are marked non-reusable at address space termination. There
  are times in the life of an ipl when an address space will
  go away and its corresponding slot in the ASVT will be
  marked non-reusable. When this occurs, the non-reusable slot
  is replaced by a slot from the RSVNONR pool.  However, once
  the RSVNONR pool is exhausted, the slots in the MAXUSER or
  RSVSTRT pool cannot be replaced and are often lost for the
  remainder of the IPL.
   When the number of RSVNONR slots falls below 5% of that
  specified in IEASYSxx, the system produces:
     msgIEA061E REPLACEMENT ASID SHORTAGE HAS BEEN DETECTED
  IEA061E is an indication that address space termination may
  soon result in a decrease in the number of active ASIDs that
  may be running (IE:  the MAXUSER or RSVSTRT pools will not be
  replenished). Again, it may require an IPL to alleviate the
  non-reusable address spaces, but the urgency of the IPL will
  depend on two factors;
   -MAXUSER slots available (indicated by ASVT +x'1E0' field
    ASVTAAV).
   -The depletion rate due to ASID termination with cross
    memory binds. RSVNONR availability can be determined via
    the ASVTANR field as shown below.
  For example, if at peak processing, 20 MAXUSER slots are
   still available (unused), and the slot depletion rate is
   5 a day, you may still have up to 4 days before an IPL will
   be necessary.
   If cross memory binds are freed, and the RSVNONR pool is
  replenished such that it is at least 10% of its original
  specification, IEA062I will be issued:
   msgIEA062I REPLACEMENT ASID SHORTAGE HAS BEEN RELIEVED
  *
     The most common reason for a slot in the ASVT to be marked
  non-reusable is that the corresponding address space has gone
  down with cross-memory connections or binds.  Due to system
  integrity concerns, the ASID cannot be reused until these binds
  are broken.  Please see APAR OY26621 for additional information
  about this problem of cross memory binds and what operational
  procedures may be performed to minimize the number of address
  spaces that terminate with unbreakable cross-memory connections.
     Note that the termination of DB2 regions is a major cause
  of slots being marked non-reusable. APAR OY26621 discusses
  non-reusability with particular emphasis on DB2 address
  spaces. For information on  non-reusability associated with
  PSF address spaces, please see JES2 apar OY22901.
  Also, see OY55392 for additional documentation on
  non-reusable slots.
     To determine if a system is, in fact, out of usable slots in
  the ASVT, the customer can look at the ASVT in an SVC dump, a
  standalone dump, or by browsing the active system if it is still
  in this problem state. The ASVT is pointed to by the
  CVT + x'22C'. The ASVT eyecatcher is located at ASVT + x'200'.
  The following data from the ASVT will confirm that the system is
  out of slots:
  
    1) ASVTANR  (+x'1E8') = 0.
      Indicating the number of free RSVNONR slots is zero.
    2) If pre HBB7709, if ASVTDSHD (+x'1FC') = x'80000000'.
      It indicates the first free RSVNONR slot is assigned.
    3) ASVTAAV  (+x'1E0') = a very low number (<=5).
      Indicating very few slots on the available queue.
    4) ASVTFRST (+x'20C') may be x'80000000'.
      Indicating the first free available queue slot is assigned.
  
  
  Again, if ASVTAAV is not low, the IPL urgency is dependant on
   the ASVT slot depletion rate.
  The slots in the ASVT begin at ASVT + x'210'. A slot has been
  marked non-reusable if its high order bit is on, and the
  address in the slot points to ASVT + x'210'. On a system
  which is experiencing a problem due to ASVT slots being
  marked non-reusable, all or nearly all slots which have
  the high order bit on will point to ASVT + x'210'.
    At OS/390 r1.2 and earlier, the system provides no way of
  identifying the job last associated with an address space
  that has been marked non-reusable. Please contact Supervisor
  level 2 if you would like further assistance in determining
  which address space(s) are contributing to the problem of non-
  reusable slots in the ASVT, or see APAR II08563 for more info.
  When contacting level 2, please have the RMID's of the
  following modules available: IEAVEMDL, IEAVESVC AND IEAVFX00.
  At OS/390 r1.3 and later, the XMSE control block in the
  private area of the PCAUTH address space (ASIDx'0002')
  contains the last job name assigned to its corresponding
  address space.  II08563 details how to locate the XMSE
  from the ASCB or ASSB.
    Once the customer has verified that the system is, in fact,
  experiencing problems due to slots being marked non-reusable,
  and once all possible operational measures have been taken to
  minimize the number of address spaces which terminate with
  cross memory connections, the following can be done to
  compensate for the lost slots.  the RSVNONR parameter of the
  IEASYSxx parmlib member should be increased so that it is equal
  to "the number of slots that get marked non-reusable per day"
  times "the maximum number of days between ipls", plus 5 or 10
  "extras". There should be no adverse effects from a modest
  increase of RSVNONR to 100 or 200 from its normal system default
  of 5. Please see OW42868 for possible CSA concerns with
  increasing MAXUSER.
  

Local fix

Problem summary

Problem conclusion

Temporary fix

Comments

• DB2INFO
  

APAR Information

• APAR is sysrouted FROM one or more of the following:

• APAR is sysrouted TO one or more of the following:

Fix information

Applicable component levels