APAR status
Closed as program error.
Error description
When a PipeLineLength=2 ("Dual Unit of Work") channel thread terminates it fails to free a block of memory and generates the following FDC: Probe Id :- XC006001 Component :- xcsFreeMemFn Program Name :- amqrmppa Major Errorcode :- xecS_I_PRIVATE_MEMORY_ERROR Probe Description :- AMQ6091: An internal IBM MQ error has occurred Comment1 :- invalid head tag MQM Function Stack rriRecvThread2 xcsFreeMemFn xcsFFST
Local fix
Set PipeLineLength=1 in qm.ini so Dual-Unit of Work threads are not used.
Problem summary
**************************************************************** USERS AFFECTED: MQ users who make use of the Dual-Unit of Work feature, by setting PipeLineLength=2 in qm.ini. Platforms affected: MultiPlatform **************************************************************** PROBLEM DESCRIPTION: The pointer to a memory area used by MQ to receive incoming messages was incorrect at the point a terminating Dual-Unit of Work thread was trying to free the memory to the system. This caused a Private Memory FDC to be generated which reported an "invalid head tag".
Problem conclusion
The MQ code has been corrected so that the memory block for the stage area is correctly freed, preventing the FDC. --------------------------------------------------------------- The fix is targeted for delivery in the following PTFs: Version Maintenance Level v9.0 LTS 9.0.0.10 v9.1 LTS 9.1.0.6 v9.x CD 9.2.0 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
IT31820
Reported component name
IBM MQ BASE M/P
Reported component ID
5724H7261
Reported release
900
Status
CLOSED PER
PE
NoPE
HIPER
NoHIPER
Special Attention
NoSpecatt / Xsystem
Submitted date
2020-02-11
Closed date
2020-04-28
Last modified date
2021-09-01
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 M/P
Fixed component ID
5724H7261
Applicable component levels
[{"Line of Business":{"code":"LOB45","label":"Automation"},"Business Unit":{"code":"BU053","label":"Cloud & Data Platform"},"Product":{"code":"SSYHRD","label":"IBM MQ"},"Platform":[{"code":"PF025","label":"Platform Independent"}],"Version":"9.0"}]
Document Information
Modified date:
02 September 2021