IT32526: QUERYING DATA FROM SYSMASTER:SYSCONBLOCK GENERATES ASSERT FAILURE

APAR status

• Closed as program error.

Error description

• Executing below query on sysmaster:sysconblock causes assert
  failure:
  
  > echo "select * from sysconblock" | dbaccess sysmaster
  Database selected.
  No rows found.
  Database closed.
  
  Which generates log as below
  
  > onstat -m
  IBM Informix Dynamic Server Version 14.10.FC3DE -- On-Line -- Up
  64 days 01:49:09 -- 256508 Kbytes
  Message Log File:
  /informixdir/tmp/online.log
  03/31/20 16:36:04 Tue Mar 31 - loguniq 168, logpos 0x526018,
  timestamp: 0xdf303a Interval: 10773
  03/31/20 16:36:04 Maximum server connections 3
  03/31/20 16:36:04 Checkpoint Statistics - Avg. Txn Block Time
  0.000, # Txns blocked 0, Plog used 7, Llog used 2
  03/31/20 16:41:04 Checkpoint Completed: duration was 0 seconds.
  03/31/20 16:41:04 Tue Mar 31 - loguniq 168, logpos 0x589018,
  timestamp: 0xdf39c0 Interval: 10774
  03/31/20 16:41:04 Maximum server connections 3
  03/31/20 16:41:04 Checkpoint Statistics - Avg. Txn Block Time
  0.000, # Txns blocked 0, Plog used 342, Llog used 99
  03/31/20 16:49:53 Assert Failed: Condition Failed (Bad
  allocation size (0) for pool 'mt' (0x44ffe040)), In
  (mt_shm_malloc_segid)
  03/31/20 16:49:53 IBM Informix Dynamic Server Version
  14.10.FC3DE
  03/31/20 16:49:53  Who: Session(374, informix@hostname, 25688,
  0x45fbf988)
                 Thread(6871, sqlexec, 45f7a548, 1)
                 File: mtshpool.c Line: 4710
  03/31/20 16:49:53  Action: Please notify IBM Informix Technical
  Support.
  03/31/20 16:49:53 stack trace for pid 30514 written to
  /informixdir/tmp/af.1ebf5890
  03/31/20 16:49:53  See Also:
  /informixdir/tmp/af.1ebf5890, shmem.1ebf5890.0
  03/31/20 16:49:59 Condition Failed (Bad allocation size (0) for
  pool 'mt' (0x44ffe040)), In (mt_shm_malloc_segid)
  
  Assert Failure file contains the following stack:
  
  afstack
  afhandler
  affail_interface
  mem_asfail
  mt_shm_malloc_segid
  mt_malloc
  mt_realloc
  mt_aio_vfprintf
  gcv_vfprintf
  ex_gcv_print
  smi_opexplain
  smi_storeexplainflags
  prconblock
  pstread
  rsread
  fmread
  readseq_single
  gettupl
  scan_next
  getrow
  fetchrow
  exfetch
  sql_nfetch
  sq_nfetch
  sqmain
  spawn_thread
  th_init_initgls
  startup
  

Local fix

Problem summary

• ****************************************************************
  * USERS AFFECTED:                                              *
  * Users of Informix Server prior to 14.10.xC4.                 *
  ****************************************************************
  * PROBLEM DESCRIPTION:                                         *
  * See Error Description                                        *
  ****************************************************************
  * RECOMMENDATION:                                              *
  * Update to Informix Server 14.10.xC4.                         *
  ****************************************************************
  

Problem conclusion

• Fixed in Informix Server 14.10.xC4.
  

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:

Fix information

• Fixed component name

  INFORMIX SERVER

• Fixed component ID

  5725A3900

Applicable component levels