APAR status
Closed as program error.
Error description
Queue manager reports object damage for a queue when the queue file size reaches 2 TB. The following failure data capture (FDC) records were generated. 2020/03/10 12:53:46.767065-5 amqrmppa 213292 562 AQ115020 aqhResizeSpaceMap STOP 2020/03/10 20:30:46.689649-5 amqrmppa 213292 564 AQ066010 aqhAllocateSpace arcE_OBJECT_DAMAGED 2020/03/10 20:30:49.065654-5 amqrmppa 213292 564 AQ060020 aqhLoadMsgChain arcE_OBJECT_DAMAGED 2020/03/10 20:30:51.415984-5 amqrmppa 213292 564 AQ056010 aqhLoadQueue arcE_OBJECT_DAMAGED
Local fix
Set a MAXDEPTH (and MAXMSGL if necessary) for the queue to prevent it from growing to 2TB.
Problem summary
**************************************************************** USERS AFFECTED: Users using very large queue files where the queue file size is expected to grow to 2 TB Platforms affected: MultiPlatform **************************************************************** PROBLEM DESCRIPTION: A defect in MQ queue object buffer handling caused the object damage when the queue file size reached 2 TB limit.
Problem conclusion
* MQ versions older than MQ 9.1.5 A design limitation of the queue implementation prior to MQ 9.1.5 means that the queue object with 2TB size can only be supported by disabling the queue buffering for non persistent messages. Procedure to disable queue buffering for non persistent messages. - Apply the fix for the APARs IT29354 and IT32393. - After applying the fix, set the DefaultQBufferSize to 0 and then recreate the queue which is expected to consume 2 TB. TuningParameters: DefaultQBufferSize=0 After recreating the queue, remove the tuning parameter or set the DefaultQBufferSize to the required value and then restart the QM so that other newly-defined queues will be created with default buffer size or the user defined buffer size( > 0). Altering this parameter does not affect queues that have already been defined. The buffer length set for the queue can by checked by dumping the queue details using the amqldmpa command. Command: amqldmpa -m TESTQMGR -c A -u 1 -q TESTQ -d 15 -f /var/mqm/trace/TESTQ.dmp.out Attribute name : StgClass.MaxQBufferLength Examples: StgClass.MaxQBufferLength 0 <--- 0 byte StgClass.MaxQBufferLength 4194304 <--- 4 MB StgClass.MaxQBufferLength 131072 <--- 128 KB (Default) * MQ version 9.1.5 MQ 9.1.5 code has been modified to prevent the queue manager encountering the problem. Apply the fix for this APAR to prevent the queue manager from encountering the object damage problem if a queue file reaches 2TB. --------------------------------------------------------------- The fix is targeted for delivery in the following PTFs: Version Maintenance Level v8.0 8.0.0.16 v9.0 LTS 9.0.0.11 v9.1 LTS 9.1.0.7 v9.x CD TBC. The latest available maintenance can be obtained from 'WebSphere MQ Recommended Fixes' http://www-1.ibm.com/support/docview.wss?rs=171&uid=swg27006037 If the maintenance level is not yet available information on its planned availability can be found in 'WebSphere MQ Planned Maintenance Release Dates' http://www-1.ibm.com/support/docview.wss?rs=171&uid=swg27006309 ---------------------------------------------------------------
Temporary fix
Comments
APAR Information
APAR number
IT32393
Reported component name
IBM MQ BASE MP
Reported component ID
5724H7251
Reported release
800
Status
CLOSED PER
PE
NoPE
HIPER
NoHIPER
Special Attention
NoSpecatt / Xsystem
Submitted date
2020-04-01
Closed date
2020-06-17
Last modified date
2020-06-22
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
IBM MQ BASE MP
Fixed component ID
5724H7251
Applicable component levels
[{"Business Unit":{"code":"BU053","label":"Cloud & Data Platform"},"Product":{"code":"SSYHRD","label":"IBM MQ"},"Platform":[{"code":"PF025","label":"Platform Independent"}],"Version":"8.0.0.0","Line of Business":{"code":"LOB45","label":"Automation"}}]
Document Information
Modified date:
23 June 2020