PH31384: ADHQ1217W REQUEST WOULD HAVE EXCEEDED MAXIMUM ALLOCATIONS VALUE

Obtain the fix for this APAR.

APAR status

• Closed as program error.

Error description

• ADHQ1217W REQUEST WOULD HAVE EXCEEDED MAXIMUM ALLOCATIONS VALUE.
  There can be a problem with accessing an internal memory object
  under certain circumstances.  Depending on the activity and
  the prior activity, the memory objects may be in a state that
  when one of these events is processed, an ADHQ1217W
  message will be generated.
  

Local fix

Problem summary

• ****************************************************************
  * USERS AFFECTED: Users of IBM Db2 Query Monitor for z/OS      *
  *                 Users of IBM Security Guardium S-TAP for     *
  *                 Db2 on z/OS                                  *
  ****************************************************************
  * PROBLEM DESCRIPTION: 1. Abend 0C4 in CQCMBNxx while          *
  *                      collecting BIND Text.                   *
  *                      2. Abend S0C4-3B where the BIND Text    *
  *                      is not available.                       *
  *                      3. ADHQ1217W REQUEST WOULD HAVE         *
  *                      EXCEEDED MAXIMUM ALLOCATIONS VALUE.     *
  *                      4. "DB2 QUERY MONITOR #SSMN SUBTASK     *
  *                      ABEND" dump if Db2 was started after    *
  *                      Query Monitor collector.                *
  *                      5. Abend 0C4-10 in CQCMSTRM at offset   *
  *                      X'12AE'.                                *
  ****************************************************************
  * RECOMMENDATION: APPLY the PTF.                               *
  ****************************************************************
  1. The process of obtaining Bind Text destroyed the access to
  the needed memory which could cause abend S0C4 or garbage in
  BIND statement text in STAP.
  2. There are certain cases on a REBIND where the BIND Text is
  not available. But Query Monitor tried always to obtain the
  text and so received an abend.
  3. Storage leak due to lack of checking the cached free list
  for various cell pools within the STAP primary memory object.
  The functions that lacked the checking (SIGNON, BINDS etc.)
  would generate ADHQ1217W messages. The impact would be lost
  events for the described functions but would not impact the
  collection of SQL and other events.
  4. When Db2 was started after Query Monitor, the routine for
  activating Db2 monitoring tried to address already freed
  memory. Addresses were left after previous start of Query
  Monitor.
  5. If Query Monitor was stopped while a very heavy workload
  was running on Db2, that could cause abend 0C4 in CQCMSTRM
  module.
  This also could cause a memory leak in internal Query Monitor
  thread blocks.
  

Problem conclusion

• 1. Programs were updated to keep access to the memory with BIND
  statement text.
  2. The check for existence the BIND Text is added before using
  it.
  3. Lack of memory for BINDS, SIGNON and Blocking would stop
  these type of events from being generated. Logic was updated
  to fix that memory leak.
  4. Logic was corrected to clear addresses when Query Monitor
  is stopping and memory is freeing.
  5. Logic was corrected to stop Query Monitor more gracefully
  under heavy workload without those abend and memory leak.
  
  Search Keywords:
  ABENDS S0C4 S0C4-3B CQCMBNB1 CQCMBNC5 CQCMSTRM S0C4 #SSMN
  SUBTASK ABEND ADHQ1217W BIND SIGNON BLOCKING STAP
  

Temporary fix

Comments

APAR Information

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

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

  UI73628

Modules/Macros

• CQC#RESM CQCISMPX CQCMB2B1 CQCMB2C5 CQCMB3B1 CQCMB3C5 CQCMB4B1
  CQCMB4C5 CQCMBNB1 CQCMBNC5 CQCMCNB1 CQCMCNC5 CQCMKMSG CQCMPRC5
  CQCMSIB1 CQCMSIC5 CQCMSTRM CQCOXGBX CQCOXGC5
  

Fix information

• Fixed component name

  COMMON COLLECTO

• Fixed component ID

  5639OLC00

Applicable component levels

• R110 PSY UI73628

     UP21/01/29 P F101

Fix is available

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