APAR status
Closed as program error.
Error description
If multiple client browser MQGETs are waiting for a message, with SHARECNV>0 then only one of them returns immediately from the MQGET. The others wait within their MQGET until their WaitInterval is finished, and then their MQGET returns to the application with the message. The message should have been made available to the other application(s) immediately. That is, their MQGET calls should have returned immediately, not after their WaitInterval had expired. The same effect is seen when using async consume MQ APIs (MQCB, MQCTL) and using a wait interval. After this, if another message arrives, then again one of the waiting browser MQGETs will return immediately, but the others will not see it till later. In each case, even though all waiting browse MQGETs were eligible to receive the message immediately, only one of them received it immediately. The others received it later.
Local fix
Set attribute SHARECNV of the server connection channel in use to 0, SHARECNV(0).
Problem summary
**************************************************************** USERS AFFECTED: Applications performing browsing MQGETs from client programs connected via SHARECNV>0 channels, and using a WaitInterval. Also applications using asynchronous consume APIs and using a WaitInterval. Platforms affected: MultiPlatform **************************************************************** PROBLEM DESCRIPTION: The list of asynchronous browsing waiters within the queue manager was re-ordered to try to ensure fair division of work between them. However, upon moving the first browsing waiter to the end of the list, the loop then immediately ended because the MQ code did not remember that there were other waiters in the list. Therefore the other waiters were not considered eligible for posting to see that message immediately.
Problem conclusion
The coding error has been fixed so that the loop will continue, and consider all waiters in the case where the first one has been re-ordered in the list. --------------------------------------------------------------- The fix is targeted for delivery in the following PTFs: Version Maintenance Level v7.5 7.5.0.8 v8.0 8.0.0.7 v9.0 CD 9.0.3 v9.0 LTS 9.0.0.2 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
IT17605
Reported component name
WEBSPHERE MQ 7.
Reported component ID
5724H7240
Reported release
750
Status
CLOSED PER
PE
NoPE
HIPER
NoHIPER
Special Attention
NoSpecatt / Xsystem
Submitted date
2016-10-21
Closed date
2017-04-18
Last modified date
2017-04-18
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
WEBSPHERE MQ 7.
Fixed component ID
5724H7240
Applicable component levels
[{"Business Unit":{"code":"BU059","label":"IBM Software w\/o TPS"},"Product":{"code":"SSDEZSF","label":"IBM WebSphere MQ Managed File Transfer for z\/OS"},"Component":"","ARM Category":[],"Platform":[{"code":"PF025","label":"Platform Independent"}],"Version":"7.5","Edition":"","Line of Business":{"code":"LOB45","label":"Automation"}}]
Document Information
Modified date:
31 March 2023