PI99450: LOGICAL UNLOAD RUN IN NATIVE MODE INTERMITTENTLY HANGS IF LOB/XML OR INDESCAN INVOLVED Z650

Obtain the fix for this APAR.

APAR status

• Closed as program error.

Error description

• (HPU 5.1 only) A logical unload (OUTDDN option) job run in
  native mode intermittently hangs if at least one of the
  following conditions is fullfilled:
  case1) LOB or XML columns are unloaded
  case 2) the indexscan feature is put into action (i.e. an ORDER
  clause which sort key matches the clustering key is specified)
  
  PB53276 WAIT
  

Local fix

• For case 2, disable the indexscan feature by specifying an
  INDEXSCAN NO option. For both case, run the unload in SQL mode
  by adding the DB2 FORCE option.
  

Problem summary

• ****************************************************************
  * USERS AFFECTED:                                              *
  * Users of High Performance Unload                             *
  ****************************************************************
  * PROBLEM DESCRIPTION:                                         *
  * PI97170:                                                     *
  * The SELECT statement written in the SYSPRINT dataset is      *
  * incorrect if the SELECT statement from a logical unload      *
  * involves a constant that contains a binary zero (0x00). The  *
  * end of the line containing the binary zero is truncated.     *
  * Only the part of the linebefore the binary zero is           *
  * displayed.                                                   *
  *                                                              *
  * PI98036:                                                     *
  * When the index scan feature is in action, the allocation of  *
  * the merge files (ddname TnnnMG) is incorrectly done with a   *
  * primary quantity of zero (the INZX111 message about TnnnMG   *
  * report used 0 K / 0 K as primary and secondary quantities)   *
  * when the following conditions are fulfilled:                 *
  * - the Maximum number of disk units to allocate a work file   *
  * (LIMUNIT) is set to 1.                                       *
  * - the amount of bytes to sort is greater than the value set  *
  * for Maximum size for primary allocation of a work data set   *
  * (WRKMXPR).                                                   *
  *                                                              *
  * PI98143:                                                     *
  * The INZU222I and INZU376I messages display an invalid number *
  * of unloaded rows when the following conditions are fulfilled *
  * :                                                            *
  * - several partitions are unloaded into a single dataset      *
  * - paralellism for LDS reading is enabled                     *
  * - OUTMAXROWS is specified                                    *
  * - the native mode is used                                    *
  * - an ORDER clause is specified and triggers a sort process   *
  * (the indexscan feature is applicable and enable does not     *
  * allow to retrieve all the selected records, in otherwords,   *
  * the indexscan ratio is less then 100%)                       *
  * - the DB2 HPU settings specify YES for the "Enforce          *
  * partition parallelism for unloading a table into a single    *
  * file (VUU036/GBLPARAL)" parameter                            *
  *                                                              *
  * However, the number of rows actually unloaded is correct.    *
  * The issue only affects the value displayed by the messages   *
  * mentioned above and the incorrect value is always greater    *
  * than the correct one.                                        *
  *                                                              *
  * PI98250:                                                     *
  * HPU terminates in ABENDS0C4 with traceback as follows        *
  *  6 obfGetNbSet +00000006 1555 INZUTILK obf.c                 *
  *  7 _inzztopoDetermineSelectProperties                        *
  *  +00000550 494 INZUTILK inzztopo.c Call                      *
  *  8 _inzztopoCreateTopology                                   *
  *  +000002B6 1307 INZUTILK inzztopo.c Call                     *
  *  9 inzztopoAnalyse                                           *
  *                                                              *
  * This occurs when the following conditions are fulfilled:     *
  *  - the tablespace to unload is partitioned                   *
  *  - the following incompatible requests are made for the same *
  * table space:                                                 *
  *    -- a logical unload (OUTDDN) to be run in SQL mode        *
  * (either because the SELECT statement is not       supported  *
  * by HPU or because the DB2 FORCE option is specified)         *
  *    -- a physical unload (UNLDDN option)                      *
  *                                                              *
  * When such a situation DB2 HPU is expected to ignore the      *
  * request for physical unload.                                 *
  *                                                              *
  * PI98842:                                                     *
  * HPU terminates with an ABENDS013-A4 when the SYSIN is        *
  * allocated with the SUBSYS parameter. This issue did not      *
  * exist in DB2 HPU releases prior 4.3.                         *
  *                                                              *
  * PI98844:                                                     *
  * The unload of the data from an image copy (COPYDDN option)   *
  * hangs when the following conditions are fulfilled :          *
  * - the input image copy is a global image copy                *
  * - the target tablespace is a partition-by-growth table space *
  * with only one existing partition                             *
  * - the output dataset is a single dataset (i.e. not partition *
  * dependent) allocated on tape via a TEMPLATE statement        *
  *                                                              *
  * PI99450:                                                     *
  * A logical unload (OUTDDN option) job run in native mode      *
  * intermittently hangs if at least one of the following        *
  * conditions is fullfilled:                                    *
  *  case 1) LOB or XML columns are unloaded                     *
  *  case 2) the indexscan feature is put into action (i.e. an   *
  * ORDER clause which sort key matches the clustering key is    *
  * specified)                                                   *
  *                                                              *
  * PI99701:                                                     *
  * 1. An ABENDS0C4 occurs when unloading LOB data into HFS      *
  * files. This occurs if the size of a LOB data is greater than *
  * 27990 bytes.                                                 *
  * 2. The number of rows in the dataset containing the unloaded *
  * data exceeds the limit set by the OUTMAXROWS option. This    *
  * occurs if the following conditions are fullfiled:            *
  * - the unload is processed in native mode                     *
  * - the data from more than one partition of a table space is  *
  * unloaded into a single dataset                               *
  * - the parallelism degree for partition processing is enabled *
  * (i.e. more than PARALLELISM n or PARELLELISM(n,,,,,,,) with  *
  * n > 1 or VUX025/PARALLEL set to a value greater than 1)      *
  * - an ORDER BY clause is specified                            *
  * - the indexscan feature is not used                          *
  * - the GBLPARAL value is set to YES                           *
  ****************************************************************
  * RECOMMENDATION:                                              *
  * Apply the PTF for problem resolution                         *
  ****************************************************************
  

Problem conclusion

• Code has been changed to fix this problem
  

Temporary fix

• PI98250:
  As this is an unsupported request, consider one of the following
  solution.
  Solution 1) remove the unintended request involved in the
  incompatibility, if any i.e. one of the following:
     + logical unload (remove the entire SELECT statement with the
  associated OUTDDN any other related options)
     + SQL mode (either remove the DB2 FORCE option if any or
  reword the SELECT statement so that it is eligible for HPU
  native mode)
     +- physical unload (remove the UNLDD option)
  Solution 2) if both the logical (OUTDDN) and physical unload
  (UNLDDN) are needed, split the request in two separate UNLOAD
  statements
  
  PI98036:
  Set LIMUNIT to a value greater than 1.
  
  PI98842:
  If applicable, do no use the SUBSYS parameter with the SYSIN
  dataset.
  
  PI98844:
  Consider unloading the data to disk or allocate the output
  dataset via a DD statement in the JCL.
  
  PI99450:
  For case 2, disable the indexscan feature by specifying an
  INDEXSCAN NO option. For both case, run the unload in SQL mode
  by adding the DB2 FORCE option.
  
  PI99701:
  Item 2: Set the parallelism degree for partition processing to
  1.
  

Comments

APAR Information

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

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

  UI57103

Modules/Macros

• INZUTILK
  

Fix information

• Fixed component name

  DB2 HI PERF UNL

• Fixed component ID

  5697F4400

Applicable component levels

• R510 PSY UI57103

     UP18/07/13 P F807

Fix is available

• Select the PTF appropriate for your component level. You will be required to sign in. Distribution on physical media is not available in all countries.