DB2 FOR LUW / DB2FORLUW / B50 - DB2

When db2set DB2_CDE_STMTCACHING=YES is set (usually set when
DB2_WORKLOAD=SAP is set)

In DPF (multi partition setup) a CDE query has to be first
executed once, cached, then executed a second time.
Depending on the memory layout the second execution can lead to
either to a trap (SEGV) or to a Memory FODC due to an illegal
memory size request.

For the trap the top functions can vary, here are a few
examples:

    ibm_cde::query::Token::decomposeLongTableName()
    ibm_cde::query::Parser::prepareCachedSTQ()
    ibm_cde::query::Parser::prepareCachedTree()
    cdeInterface::initializeData()

or

    ibm_cde::query::SyntaxTree::iterator::goToNext + 0xD8
    ibm_cde::query::SyntaxTree::iterator::reset + 0x190
    ibm_cde::query::SyntaxTree::iterator::iterator + 0x100
    ibm_cde::query::Parser::prepareCachedSTQ + 0x100
    ibm_cde::query::Parser::prepareCachedTree + 0x340
    ibm_cde::query::Parser::prepareCachedQuery + 0x1F0
    cdeInterface::initializeData + 0xB08

The Memory FODC might also have different stacks but the size
will be huge:

    sqloGetMemoryBlockExtended + 0x41C
    ibm_cde::services::Heap::allocMem + 0x115C
    std::basic_string::_Copy + 0x8C
    std::basic_string::basic_string + 0x1E0
    ibm_cde::query::Token::decomposeLongTableName + 0xB8
    ibm_cde::query::Parser::prepareCachedSTQ + 0x1C4
    ibm_cde::query::Parser::prepareCachedTree + 0x340

  FUNCTION: DB2 UDB, SQO Memory Management, sqlogmblkEx,
probe:1000
  MESSAGE : ZRC=0x820F0004=-2112946172=SQLO_MEM_SIZE "Mem Mgt
invalid size"
            DIA8563C An invalid memory size was requested.

  DATA #4 : Requested size, PD_TYPE_MEM_REQUESTED_SIZE, 8 bytes
  648535941969828448

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* USERS AFFECTED:                                              *
* ALL                                                          *
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* PROBLEM DESCRIPTION:                                         *
* See Error Description                                        *
****************************************************************
* RECOMMENDATION:                                              *
* Upgrade to Db2 11.5 fp1 or later                             *
****************************************************************

db2set DB2_CDE_STMTCACHING=NO

not known / see Local fix

forerunner  : IJ15638 
follow-up : 

Date  - problem reported    :
Date  - problem closed      :
Date  - last modified       :

31.10.2019
31.10.2019
31.10.2019